The (renewable) electron economy, part 9
A choice of primary energies: renewable electrons win the gold 58
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Posted 11:16 AM on 26 Aug 2008
by Michael Hoexter -
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BILL HANNAHAN Posted 5:21 am
26 Aug 2008
The most important thing Jeff Bingaman said in his interview is that
http://gristmill.grist.org/story/2008/8/26/84242/0808
"It is presumptuous in my view to suggest that we know where we need to be in 2050"
We should not be trying to cherry pick technology; we should be creating a system that will automatically develop the best technology. Our debate should be how best to do that.
If we implemented the McCain energy program and the Obama energy program in parallel, each with full funding, it would still lead to disaster because they are both woefully inadequate.
We need a fully integrated energy plan for the future. It is like a jigsaw puzzle with many interacting pieces. The candidates pick out one piece from the opponent's plan and say, "This won't solve our energy problem by itself, so there is no point in doing this". That argument could be applied to every piece of the puzzle.
There are 3 billion people around the world who want to join the middle class. If the U.S. could reduce its emissions to zero instantly, the savings would be gobbled up by the developing world.
The most important goal for the U.S. is to use our technical capacity to develop low emission energy sources that are less expensive than fossil fuel. People across the world will switch to the new less expensive sources quickly and voluntarily, not kicking and screaming.
SHORT TERM STRATEGY
1 Drill, drill, drill. Drill in Alaska, drill offshore, drill wherever we have oil and gas. Each $10 per barrel that oil goes up costs Americans another $80 billion per year. Each 1 cent per kWh that electricity goes up costs Americans another $40 billion per year.
We need fuel to keep our economy going so that we can afford to develop the new technologies that the world needs.
2 Level the playing field so that we are forced to pay the true cost of energy from each source. Eliminate all energy subsidies.
When you take a load of trash to the city landfill you pay a fee per pound of trash. Humans have been using the atmosphere as a free waste dump since we gained control of fire. Atmospheric dumping of hazardous material is producing severe adverse effects on human health and global climate. We should charge an atmospheric dumping fee equal to the best estimate of the cost of damage done by the toxic waste being injected into our atmosphere. Low emission technologies will become more competitive on a level playing field.
3 Conservation is a strategy that is being implemented already due to rising energy costs, and it will increase. Improving insulation and using more efficient appliances make good sense.
Conservation sometimes comes at a high cost. For example sales of motorcycles and mopeds are exploding. The motorcycle fatality rate per mile is seven times higher than for cars. The fatality rate for bicycles is seven times higher than motorcycles. Econobox cars are less survivable in accidents than large cars built with the same level of technology.
Higher electricity prices mean less security lighting. There'll be more muggings and rapes on college campuses and parking lots. Homes will be colder in winter and hotter in summer. More people on limited income will have to choose between paying for food, medicine or utility bills.
The cost of conservation includes increased human suffering and death. The sooner we develop clean safe abundant sources of inexpensive energy, the sooner we can minimize these costs.
INTERMEDIATE TERM STRATEGY
Use proven technology to reduce our dependence on foreign oil.
1 Accelerate the mainstreaming of emerging technologies including hybrid, all electric and fuel cell vehicles.
2 Mass produce floating nuclear power plants to increase our supply of clean emissions free energy electricity. A company called Offshore Power Systems built a facility to do that in Florida during the seventies, but it was never put into production due to a downturn in the economy that stalled growth and canceled orders.
3 Convert most stationary application of natural gas to electricity. Use our natural gas supply to displace imported oil. Automakers can make dual fuel vehicles, gasoline / natural gas, quickly and cheaply.
LONG TERM STRATEGY
1 Increase R&D for energy by more than a factor of ten to $100 billion per year, 90 cents per day for each of us. Push every technology as hard as possible, build prototypes of everything as it becomes possible and publish the performance data.
When someone says R&D most people only hear "Research". In truth Development is the really expensive part, and the U.S. has done very little of that in recent decades.
Build intermediate scale plants of all promising technologies, advanced nuclear, cellulosic biofuel, solar power, geothermal, coal with full sequestration. For those technologies that are successful in medium scale we should built at least one full scale commercial size plant.
We have yet to build a fully sequestered coal plant after years of talk. We need to try even if the first plant is a failure.
There are dozens of ways to split a uranium atom. What are the odds that a steroidal submarine reactor is the best? There are huge improvements to be made in nuclear power plant design and construction, yet we have not built a new experimental reactor since 1973.
2 Spaceship earth is less than 8,000 miles in diameter and covered largely by water. With the appropriate use of technology it could be a near paradise for 500 million to 1 billion people, without putting too much stress on the other species that share this planet, but we are over 6 billion, headed for 10 billion, with two thirds living in poverty.
Earth can never be paradise for 10 billion people, unless your idea of paradise is sitting in an air conditioned high rise apartment building, surfing the internet, eating insect pate. It will take a massive infusion of technology to provide a comfortable life for all those people while preserving whatever is left of the environment.
Population has to be on the table in any serious discussion of the future. The U.S. population has more than doubled since WW II. Had we stabilized it at that level we would have abundant inexpensive energy, water and food supplies.
CONCLUSION
The road of progress is paved with stones of failure. By spending 90 cents per person per day to push every technology as fast as possible, the best technologies and breakthroughs, whatever they are, will emerge as leaders in the shortest possible time. 95% of that money will probably be wasted on unsuccessful technology, but that is cheap insurance to assure that we get the best solution. Relying on a bunch of gray haired law school graduates in Washington to cherry pick technology is a formula for disaster.
The new technologies will tend to suppress rising energy costs. I believe the savings could surpass the annual R&D cost within 15 - 20 years, and save over $2,000 per year per person within 30 years, not to mention a large improvement in the environment and quality of life with this approach. 100 years from now energy will be cheap, clean and abundant.
A big R&D push will provide the U.S. with new products that are highly desirable all over the world, providing Americans with high paying manufacturing jobs and products to sell overseas to eliminate our trade deficit and strengthen the dollar.
I support nuclear power, yet this is the most anti nuclear recommendation possible because it maximizes the probability that some technology better than fission will be developed.
Things Everybody Should Know About Energy
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Charles Barton Posted 8:42 am
26 Aug 2008
Lets first examine Hoxter's views on conventional nuclear power. He lists the pros and cons as:
Pro
* Carbon neutral under operation
* Established technology with track record of producing electricity with few safety incidents
* Produce power in the same profile as most coal generation plants (a constant baseload); can be used as a coal substitute
* Remaining Uranium 235 supply functions as an energy store that can be tapped into at will
* Nuclear power enables power production in areas with poor natural and renewable resources
* Nuclear fuel is compact and highly energy dense
Con:
* Produces large amounts of highly radioactive nuclear waste that will need to be stored for millenia in isolation from the biosphere.
* The uranium enrichment process can also produce higher concentrations of U235 suitable for nuclear weapons.
* The Chernobyl reactors were pressurized light water reactors; accidents and assaults on these plants have a chance of resulting in catastrophic releases of radioactive materials
* Naturally occurring, economically extractable U235 will run out sometime in the latter half of the 21st century, especially if new nuclear plants are built out aggressively.
* Constructing nuclear power stations takes over 5 years making them ineffective in a crucial period of climate change
* Inclusive of insurance costs, which are so high that they must be assumed by governments and therefore taxpayers, nuclear power stations are very expensive.
We see in the cons express standard anti-nuclear myths. Thus of several potential uses of nuclear waste, only approach usually targeted by the anti-nukes - long term storage - is mentioned. Thus the problem is expressed without noting all of the options. The second con is an attempt to tie reactors to nuclear weapons. This is typical anti-nuclear trick. In fact two 1953 British nuclear test showed that plutonium produced in civilian reactors was not satisfactory for weapons. The third con is reflects either Hoexter's ignorance or his dishonesty. The Chernobyl reactors are not pressurized light water reactors. In fact they are water cooled, graphite moderated reactors. This is a very differ reactor technology, a type of technology that has unique safety problems, that it does not share with light water reactors. The unique safety issues of the Chernobyl type reactor played a critical role in the infamous Chernobyl accident. U-235, contrary to Hoexter's claim is not about to runout. There are four and one half billion toms of Uranium in the oceans, and it is recoverable using low cost, unsophisticated technology. Because renewables produce electricity intermittently, standard reactor produce from 2 to four times as much electricity as renewable power generators that claim equivalent power outputs. Thus a billion watt reactor produces the equivalent of a 2, 3 or even 4 billion watt renewabls generating facility. ectricity. The alleged insurance cost of nuclear power are in fact not paid by the tax payers. Instead they are theoretical obligations of the government in the event of a very large and very improbable reactor accident. In fact insurance premiums on new and highly safe nuclear plants would not be excessive, and well within the reach of plant owners. Thus Hoaxter offers a weak case against conventional nuclear power
Hoexter continues by offering an assessment of the risks and disadvantages (of alternative nuclear power)
* The described future nuclear system is more than a decade and perhaps decades away. Climate change is upon us now.
* All nuclear power irreversibly transforms its fuel into less energetic fuels; even after thousands of years it will run out
* The promised benefits may not materialize.
* The complexity of these proposed systems is very high, making oversight difficult and increasing the potential for unforeseen difficulties and consequences
* As yet uncharted safety issues will emerge with new radioactive fuels or coolants like liquid fluorine.
* Developing these systems would be a major expense drawing on government research funds diverted from less elaborate technological systems like renewable energy and energy storage.
* Existing fuel reprocessing systems have proliferation risks attached; they isolate plutonium.
* The compact power of fissionable elements may have more appropriate uses in some future technology (spaceships?) other than power generation for daily use.
Of course it is a technological possible to build conventional nuclear power plants until alternative technology plants are ready. The notion that we will run out of nuclear fuel even after thousands of years is a myth. Sufficient recoverable nuclear fuels exist in the crust of the earth that nuclear power can be used for millions of years with the use of alternative nuclear power. LFTRs represent largely proven technologies. Thus the prospect for successful development are excellent. LFTRs are not highly complex. They are indeed less complex than light water reactors. Radiation safety issues in relation to the thorium fuel cycle are well understood, have been tested. Fluoride salts as reactor coolants and fuel carriers have been well tested in two prototype reactors, and have been investigated by nuclear chemists for years. The chemistry of fluorides are well understood. One reason for choosing liquid fluorides as coolant/fuel carriers is their high level of safety. Much of the basic research on LFTRs were completed between 1950 and 1976, in addition many other issues related to the LFTR have been the subject of unrelated technical research and development, and thus now technologies are available without added research costs. The IAEA has designated thorium cycle LFTRs as a proliferation resistant technology. Thorium fuel cycles reactors produce minimal amounts of plutonium. The Hoexter's notion that the power of uranium and thorium can be used without fission reflects a complete lack of understanding of nuclear science.
Now we come to Hoxter's account of renewables. In this case I will look at both the Pros and the cons:
Pro:
* Carbon neutral or negative (in certain conditions) under operation
* Primary energy (fuel) is free
* Generators can be scaled from very small to very large; investment amounts can range from a few hundred dollars to several billion dollars.
* Primary energy is virtually endless
* With the exception of biomass and certain geothermal wells, have no non carbon emissions
* Mature or rapidly maturing technologies in most categories of renewable generator.
* Deployable within a few months to a few years for most technologies (within critical period to reverse emissions trends)
* Dependent upon a diversity of primary energies
Con:
* Many renewable energies are periodic or intermittent
* Renewable energies occur naturally as energy flows rather than energy stores or stocks (with the exception of biomass); an all-renewable grid needs to build up and carefully manage stored energy.
* Overreliance on biomass, the primary natural energy storage medium, may tax soil and the biosphere.
* The reduction in solar energy around the winter solstice may present challenges for a solar-dominant all-renewable grid especially during times of low wind.
* Catastrophic reductions of solar radiation (i.e. volcanic eruptions) can reduce the main energy in-flows; solar radiation is important to both solar and wind generators.
These list are deceptive, and hide significant problems. For example there are significant seasonable and day night variations in winds in many parts of the United States. Summer winds are much weaker than winter winds, thus little wind generated electricity may be available during periods of peak summer demand. While sun light is available during 8 hours a day in the Southwest, in much of the rest of the United States only an average of 5 1/2 hours of sunlight a day is available. The mass energy storage technologies required by an all renewable grid not been developed to the point of economically viability, and expectations that they will be developed in the next 10 years may not be realistic. Indeed it would be much more expensive to develop energy storage technologies, than to develop alternative nuclear technology. In addition the cost of mass building of renewables may be as expensive as alternative nuclear power, with out the advantaged of assured 24 hour a day power.
Thus Hoexter makes his case against nuclear and alternative nuclear power by manipulating information. He also attempts to make the case for renewables stronger by similar methods. Thus Hoexter does not offer us strong arguments in support of his contention, rather he chooses the path of misinformation to support his claims.
Charles Barton
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Bob Wallace Posted 9:21 am
26 Aug 2008
We're already deep enough into that hole. No need to dig further down.
Rather than use our capital to extract more oil from the earth and release more already sequestered carbon into our atmosphere we should:
1. Push for further conservation of oil already drilled. This is pretty much automatically happening because of high oil prices. Do nothing to lower oil prices, put pressure on/help car manufacturers to bring more efficient cars to market, and build more public transportation. Encourage building practices that lead to less driving.
We've got plenty of oil to get us through the short term while we move to electricity.
The next generation of PHEVs/hybrids should take us well over 50 mpg. The world is going to experience less than a 2% annual decrease in oil supply. We can conserve well above that with little to no pain.
2. Create a very favorable climate for renewables. Provide generous funding for research, provide financial assistance for promising technologies, and use public money as needed to create the power grid that we need for the future.
Especially fund storage research. We know how to capture energy inexpensively using wind. Wind is so cheap that private money is pouring into new wind farms. Solar prices are dropping quickly. What we need is a few hours of efficient storage to bridge the gaps.
Save natural gas for our 'last resort' electricity response until we get adequate storage. Don't burn it up now just to power our rides.
(And that conservation = danger crap? It's crap. LED lighting conserves huge amount of electricity. Insulation is relatively inexpensive and helps both with heating and cooling. Small cars can be built that are very safe. If necessary, drastically drop the speed limit for big SUVs/trucks until they die a natural death.)
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Jonas Posted 9:26 am
26 Aug 2008
These are the carbon footprints of electricity from renewables:
-solar PV: up to 100 kg CO2eq/MWh
-wind onshore: 30 kgCO2eq/MWh
-biomass without carbon sequestration: 30 kgCO2eq/MWh
-large hydro: 20 kgCO2eq/MWh
-small hydro: 5 kgCO2eq/MWh
-biomass with carbon sequestration: up to -1000 kgCO2eq/MWh
Yes, that's right minus a ton for biomass.
So it would be better to rewrite the piece and add that of all the renewables, only biomass has the capacity to generate carbon-negative energy. All other technologies remain carbon-positive.
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Jonas Posted 9:30 am
26 Aug 2008
-biomass based carbon-negative energy is the largest wedge of all wedges, in an aggressive scenario that aims to cut emissions by 80% by 2050
-biomass has a wedge here of 23%, higher than all other renewables combined
[See the Bellona Foundation's scenario, and Hansen, of course, who even goes 350ppm].
-biomass can be used in entirely existing infrastructures at a very low cost, and provide a robust baseload, making the other renewables independent of coal
-biomass used in biochar systems can restore the earth's soils, perhaps the most important ecosystem service of the coming centuries
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BILL HANNAHAN Posted 1:10 pm
26 Aug 2008
Your right Bob, but it is still underground, that is why we import 70% of our oil. Drilling will not lower the price, ask any Democrat. The reason for drilling is to keep $100+ in this country for each barrel we produce and use the money to develop technology better than oil. Why do you want to continue giving $700 billion per year to people who don't like us?
" Create a very favorable climate for renewables. Provide generous funding for research, provide financial assistance for promising technologies, and use public money as needed to create the power grid that we need for the future. "
Right again Bob. You know that we have lost a substantial fraction of our topsoil and a large fraction of our potash in a very short span of geologic time. In a few billion years the sun will run out of fuel and consume the earth in its bloated fireball long before the earth runs out of uranium.
Nuclear power is more renewable than biofuel, wind or solar.
Things Everybody Should Know About Energy
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Michael Hoexter Posted 2:09 pm
26 Aug 2008
You have a curious hole in your understanding of how biomass arrives at a biomass power plant: it grows in the ground and is watered by precipitation from the sky. These factors limit the amount of biomass that can be extracted and burned from ecosystems. Soils suffer if too much organic matter is extracted from them or we lean too heavily on the water system for woody or other biomass. In your blind advocacy for biomass, you seem to have left that out.
I am not against using biomass, biochar, biomass with CCS, etc. Only that those uses need to be assessed carefully as to their impact on the biosphere. A society with our level of power needs has never used biomass exclusively to power electric devices, etc. Blind advocacy is not the way forward in guiding us to appropriate and valuable uses of biomass in the power industry.
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Bob Wallace Posted 2:44 pm
26 Aug 2008
I have a major problem sending so much money overseas in order to purchase oil from folks who don't like us. I'm on the very same page as you are here. But I fail to see how increasing our rate of extraction is in our best interest.
Rather than speeding up the use of our own oil, why not put our emphasis on lowering our overall use?
We can't get much US oil to the pumps in the next ten or so years. We can move from personal vehicles that get ~20 mpg to ones that get ~100 mpg in ten years.
(The Google plug-in conversion Prius fleet gets
90+, combined city/highway.)
By rapidly moving to that level efficiency we could cut our overseas oil purchases by a huge amount and get close to the point where we could supply our needs from existing US wells.
IIRC approximately 50% of US driving is done using cars that are 5 or less years old. Create an atmosphere where it's made easy to purchase (finance) super efficient cars and we could make the switch in an efficient manner.
Look, we all know that the easy oil has been burned. While there's lots and lots in the ground getting to it is only going to get harder and harder. (And more and more expensive, whether it comes from within or outside the US.)
We're going to have to get off petroleum sooner or later. Why postpone the inevitable?
Why not invest in America's future rather than flying a holding pattern? If we put our efforts into building wind and solar we create American jobs. If we support US car makers who can deliver electric/hybrid cars we create American jobs.
--
As for nuclear, I used to live not far from the shut down Ranch Seco reactor. I now live not far from the shut down Humboldt Bay reactor. Both done in by what I call the 'doofus' factor.
When I see people talk about the wonderful advantages of nuclear I think about how these idealized plants will get built and operated by humans. And how among these humans will likely be a fair share of doofii. (Doofi? Or Homer Simpsons, if you please.)
Just take an objective look at the continuous string of 'incidents' at existing nuclear facilities and you will have to admit that what works great on paper falls a bit short in the real world. Leaks, fires, spills, sleeping security squads, ....
I add to that the very high cost of nuclear, the long construction time, and the high public resistance, and I ask "Why bother?".
Seems to me that we spend more money, take longer to get a flow of power, have to suffer through a lot of political battles, and take unnecessary risks just to create the latest whiz-bang atom-tweaking technology.
Solar and wind along with possible tidal and geothermal will do the job. We just need to build them out and build adequate storage. Private money will finance most of the implementation once we're over the major hurdles. Nuclear can only be built with major contributions from our tax dollars.
With renewables we spread the jobs around the country. We bring some good jobs to places like the upper mid-west that are hurting.
We create zero potential disasters.
We can upgrade/replace smaller installations as new and better technology appears. We won't need to keep a plant going for decades until it finally pays for itself.
I'd be for nuclear if it made sense.
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ClaudeB Posted 5:13 pm
26 Aug 2008
And as a Quebecois, I'm well aware of them. 20 years ago we took a lot of heat in the US for building large reservoirs and thousands of miles of 735kV power lines. More recently, the deployment of wind farms in the Gaspé peninsula were faced with opposition and backlogs from overbooked turbine manufacturers.
Have we made the right choices then? For one thing, we don't have to make the same kind of decisions you're faced with in the next decade.
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vakibs Posted 7:19 pm
26 Aug 2008
I was really warming up to you based on your analysis on nuclear power. Even if it had a distinctly pessimistic tone, at least your essay stayed true to facts.
Now your current essay on renewable power is littered with utter falsehoods. The most criminal of the statements you have made is this and about 1 percent of the area of the world's deserts could generate all the power that the world currently uses.
Now take a pencil and paper (or your calculator) and work out the numbers.
The energy density of midday sunshine is 1000 W/m^2. You solar freaks have a tendency of using this number for calculating the amount of land required for producing the required electricity.
It doesn't work like that.
You have to account for night-time and cloudy days. The average energy density of sunshine available will be multiplied by some factors (0.3 * 0. 6 * 1000) = 180 W/m^2
Further your favorite technology will convert only a part of this sunshine into electricity. The best solar PV we have is about 20% to 30% efficient. The laws of physics say that we cannot obtain beyond 60% efficiency.
Concentrated solar power (CSP) is worse than PV. You will lose a lot of solar power, as it gets repeatedly reflected by mirrors. The energy denstity of CSP is 18 W/m^2.
Use this number and not 1000 W/m^2 to calculate how much land we require for obtaining our energy needs. You will be in for some surprise.
We need an area of 1000 X 1000 sq-kilometres. And this is nowhere close to 1% of our desert areas. Further, this is the required number for current electricity needs. Future needs will be higher as developing countries demand more energy. We need two squares of 1000 X 1000 sq-kilometres.
This area is not impossible to find on earth. But it requires much more investment than you think of, and it will have a lot more impact on the environment.
The most important "con" of renewable power is It is diffuse , and consequently, it will have a higher impact on the environment due to mining, soil use and other requirements. So the most important number that needs to be mentioned for your favorite renewable technology is energy density .
Please read the chapter 25 (page 191) in the book of Prof David Mackay. You will get the basics of the physics behind concentrated solar power. Until you understand the basics, you are disqualified to even speak about it.
I can say that I excrete enough amount of material everyday to satisfy the energy needs of the earth for a whole year (by using the mass-energy-equivalence e=mc^2). But this doesn't mean this mode of energy production is feasible.
When you mention about how much solar energy falls on the surface of earth, how much power is there in waves.. this is equally bonkers. These numbers have absolutely no meaning. Got it ?
Let's think in terms of eco-dollars.
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GRLCowan Posted 11:42 pm
26 Aug 2008
True if by "worse" you mean "better".
You will lose a lot of solar power, as it gets repeatedly reflected by mirrors. The energy denstity ...
power density ...
of CSP is 18 W/m^2.
Use this number and not 1000 W/m^2 to calculate how much land we require for obtaining our energy needs. You will be in for some surprise.
We need an area of 1000 X 1000 sq-kilometres...
To make 18,000 GW (electric), according to your 18-W/m^2 estimate of year-round average production. What do you consider the world's present electrical wattage needs to be, 'vakibs'?
--- G.R.L. Cowan
How the car gains nuclear cachet
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GRLCowan Posted 12:01 am
27 Aug 2008
--- G.R.L. Cowan, H2 energy fan 'til ~1996
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vakibs Posted 12:07 am
27 Aug 2008
The current electricity demand of the world is around 2000 GW.
But this is only a portion of our total energy needs (we need a lot of energy for food, transport, stuff and so on). Counting all this, the current energy demand of the world will be around 15000 GW.
I am just quoting from the elaborate analysis done by Prof David Mackay. His book is a highly recommended primer, for anyone who is interested in sustainable energy.
Let's think in terms of eco-dollars.
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vakibs Posted 12:08 am
27 Aug 2008
It is less efficient than solar PV with respect to its energy density. (We can always hope future PV to be produced in a less expensive manner. Right now, it is purely of theoretic interest).
Let's think in terms of eco-dollars.
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amazingdrx Posted 12:21 am
27 Aug 2008
The old baseload, always maximum possible load following grid won't do for this energy re-evolution. Trying to imitate it with huge CSP and a huge new HVDC buildout isn't the best way to go.
Demand must be adjusted to match renewable supply using smart grid technology. You may not have heard, but Xcel is working on this, un-aided by recalcitrant government policy. They are shutting down two coal plants. An unprecedented, barely noticed (by mass delusional media or most energy "experts") move into the future.
Are we going to leave one utility company to shoulder this whole energy re-evolution, or join in and help them out? Your call to ape the baseload old energy economy strategy with renewables is not helpfull.
I'm looking forward to redemption in your upcoming segment. Thanks for your efforts anyway though, either way. Hope you keep contributing here in future!
ps. Sorry to pile on after the vacuuous (nothing but ad hominem) one has already flung feces at you. Hehey.
http://amazngdrx.blogharbor.com/blog John Schneider, Northern Wisconsin
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amazingdrx Posted 12:28 am
27 Aug 2008
http://amazngdrx.blogharbor.com/blog John Schneider, Northern Wisconsin
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vakibs Posted 12:50 am
27 Aug 2008
He has a doctoral degree in physics.
He knows his numbers.
If you find any mistake in his calculations, do write to him. You can reach him on his blog.
Sorry to disappoint you amazing, but I am a person who is serious about the environmentalist cause. I cannot let nonsense pass unchallenged.
Frankly, I didn't expect this from Michael. I really liked his earlier articles. Though Michael takes the silver medal for environmental idiocy, you take the gold. Your kitchen-job sources of producing energy will not be sufficient for even an iota of our needs.
The environmentalist community cannot afford to live in .. what is the right word.. "fools' paradise". Why don't you guys get real about the task ahead of us ?
Let's think in terms of eco-dollars.
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amazingdrx Posted 1:10 am
27 Aug 2008
Oooh, you follow his text in computer science? Yep that makes him an energy expert. No doubt about that.
Maybe you should check out his own admission of a lack of expertise in renewable energy.
http://amazngdrx.blogharbor.com/blog John Schneider, Northern Wisconsin
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vakibs Posted 1:35 am
27 Aug 2008
I can never reach your heights of insulting other people. Whatever rebukes I have given in my comments, they are rightly deserved. They are not personal. In fact, I highly admire all you people on this blog because I know you care for the environment.
But misleading facts and outright lies deserve my contempt. Don't they ? If you want to keep arguing, do so with numbers.
For presenting a sustainable energy plan, you don't need to be an "expert". All you need to do is proper accounting. If your numbers don't add up, it means you have failed the very first examination. Expertise will come much much later.
Let's think in terms of eco-dollars.
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amazingdrx Posted 2:00 am
27 Aug 2008
He quoted the notorious eco-traitor Moore on nukes. He simply goes out of his way to misunderestimate (a duuhbya word, that is real?) renewables and conservation at every turn.
He is biased, then uses numbers to support his bias. Can't find it right now, but I distinctly remember him disclaiming his expertise in renewavle energy, he only claims to be a numbers man. It's all in the numbers...man.
A widely held dislike of "wondertoys", as JMG puts it, seems to be at the heart of his critique. It's nukes or go back to agrarian feudalism say the wondertoy critics, hehey.
http://amazngdrx.blogharbor.com/blog John Schneider, Northern Wisconsin
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vakibs Posted 2:22 am
27 Aug 2008
Environmentalist movement of these days is turning into a religious movement. If the upper Ayatollahs don't agree with you, you will be banished as a heretic. Dr Patrick Moore has thus become an "eco-traitor".
Before you give the book of Dr Mackay a serious study, you will peek into his nuclear chapter and see if he loves nuclear. If he does, bad guy. You will not listen to him.
It doesn't work like that. You should criticize a theory based on numbers. Point out the mistakes in the calculations of Dr Mackay. Point out whether he is making any false assumptions. Give some constructive criticism. I am sure that he will accept it whole-heartedly.
It will not be long before the Ayatollahs condemn the very Dr James Hansen (as he was recently seen providing support for breeder reactors). David Roberts of grist.org was already seen twitching his lips at the very first comment.
Don't you see a pattern here ?
You are ostracizing all the reputed scientists out of the community. As I was mentioning in another post to Wolverine, environmental studies is a scientific discipline. It needs to be done with the best regard for numbers and facts.
Let's think in terms of eco-dollars.
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hapa Posted 5:23 am
27 Aug 2008
"environmental idiocy" stee-rike two!
"ayatollahs" strike three!
Don't you see a pattern here ?
yer out!
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hapa Posted 5:46 am
27 Aug 2008
~50,000,000 sq.km. worldwide "desert area"
And this is nowhere close to 1% of our desert areas.
yeah, more like 2%.
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BILL HANNAHAN Posted 12:56 pm
27 Aug 2008
It reduces the flow of money overseas.
" Rather than speeding up the use of our own oil, why not put our emphasis on lowering our overall use?
We can't get much US oil to the pumps in the next ten or so years. We can move from personal vehicles that get ~20 mpg to ones that get ~100 mpg in ten years. "
The manufacturers cannot ramp up that fast, the fleet does not recycle that fast, I still have my 1984 Supra with 200K. Personal cars are only about 1/3 of the issue, that still leaves trucks busses ships planes etc.
" We're going to have to get off petroleum sooner or later. Why postpone the inevitable? ... Why not invest in America's future rather than flying a holding pattern? "
Bob, review my recommendation, $100 billion per year is over 20 times more than we are doing now. It will accelerate the change.
"Just take an objective look at the continuous string of 'incidents' at existing nuclear facilities and you will have to admit that what works great on paper falls a bit short in the real world. Leaks, fires, spills, sleeping security squads, ....
I add to that the very high cost of nuclear, the long construction time, and the high public resistance, and I ask "Why bother? "
If humans were infallible nuclear power plants would be much cheaper and easier to build. No containment building, no triple redundant control system, no triple redundant high pressure injection system, no triple redundant low pressure injection system, no triple redundant diesel generators etc.
When human error or mechanical malfunction crashes an airliner people die. When a human error or mechanical malfunction crashes a well built nuclear plant stockholders shed a tear.
The public is warming up to nuclear and people who live near existing plants are more pro nuclear than the average population. People who live near wind farms are more anti wind than the general public.
"Solar and wind along with possible tidal and geothermal will do the job. We just need to build them out and build adequate storage. Private money will finance most of the implementation once we're over the major hurdles. Nuclear can only be built with major contributions from our tax dollars. "
I support massive R&D to develop better technology. I do not support subsidies. Subsidies distort the market resulting in inefficiency that increases waste and lowers quality of life. The best technology will win out on a level playing field, do you support a level playing field?
Things Everybody Should Know About Energy
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Michael Hoexter Posted 1:19 pm
27 Aug 2008
Yes, I stand corrected re: 2% vs. 1% of the world's deserts. I make the assumption that we will reduce our (per capita) energy usage (i.e. get radically more efficient) before we ever get to using a substantial portion of the deserts to power society. So I don't see us using 2% of the deserts for power generation...it might happen but I think we will be using a much more diversified portfolio of generators several decades into the future. On the other hand, we have the best chance of shutting down coal plants by rapidly scaling up solar thermal with storage in the next few years while pursuing an aggressive energy efficiency program. These solar plants can be built more quickly than nukes, especially the experimental variety in which, Mr Barton, for instance, puts so much faith.
Dr X,
You have your pet technologies, which you feel are the most important. If I emphasize technologies that are not your favorites I don't know if that exactly "endangers" my plan. My main concern is linking the strongest primary energy flows with power demand. Biomass and biogas are important but need to be used carefully because they are, relatively scarce, dispatchable renewable resources. The concept of a combination renewable power plant encompasses any and all renewable technologies and coordinates them; within the context of such a plant we would get the maximum utility out of biomass derived energy. So, I don't feel that I have omitted renewable technologies though my emphases are different than yours.
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amazingdrx Posted 2:09 pm
27 Aug 2008
Smart grid technology that adjusts demand is the new wave. Fractal distributed smart grid switching in every home and power source that takes its cues from internet over the grid.
I admit I have a bias towards biogas from waste, organic ag, and the GHG offsetting characteristics of this technology. And an intense distrust of any technology involving combustion of biomass.
A great series of articles overall. You have me calling this "the renewable electron (energy) economy" now too.
Good job! Thanks for your efforts. We really do have the same goal, just disagree about the best way to get there.
But without disagreement this blog would be unread, hehey.
http://amazngdrx.blogharbor.com/blog John Schneider, Northern Wisconsin
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vakibs Posted 7:10 pm
27 Aug 2008
I don't have a special love for nuclear power. If your argument that 2% of our desert areas will be sufficient to replace all our energy needs, I will be the happiest man on the planet. The point is I am not convinced. Try to accept the criticism in the proper manner, which will be to work out the numbers.
What is the desert area in the world ?
What is the power requirement of the world in your opinion ? Is it 2000 GW or 15000 GW or any other number ? It will be better if you break the demand into different domains (transport, heating, production of stuff etc..), like how it has been worked out by Dr. Mackay. Please also explain if you look for an equitable energy distribution in the world or do you not care ?
What is the energy density (power density)
that you assume for concentrated solar power ? If it is different from the 18 W/m^2 that has been worked out by Dr. Mackay, please explain your assumptions.
3) If your desert grid is located quite far away from the urban locations, you have to work out for the losses in the transmission. Please show those numbers as well.
Then you show me the calculations. I will not trust you until I see your numbers.
After this is done, we need to work out on two more issues
What is the expected cost in current US $ for this mega CSP project. Apparently DESERTEC costs 75 billion US $.
More importantly, what is the environmental cost for this mega CSP project. How many mirrors have to be constructed, what is the corresponding CO2 emissions in this process, are there any scarce elements that are needed in this endeavour, what are the operating costs for maintaining this CSP plant (in terms of water requirements for cleaning, material replacement etc..)
Unless you show these numbers, I will not be convinced. I agree with you that nuclear power is only our 2nd choice for energy production. But I think we need nuclear power, because solar power will not be sufficient enough.
So the easiest way to convert me to the solar camp is to prove that solar power is indeed sufficient. So please show the numbers.
Amazing :
Point noted. I will keep looking out for all the tongue slips that you might do over this blog. The next time I catch you insulting some one, you will receive the same treatment.
Let's think in terms of eco-dollars.
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vakibs Posted 8:05 pm
27 Aug 2008
Please point out on a map of the world the 1,000,000 sq.km required for the CSP idea.
Wikipedia says this about the 10 largest deserts in the world :
Antarctic (Antarctic) 14 000 000
Sahara (Africa) 9 000 000
Groenland (Arctic) 2 000 000
Gobi desert (Asia) 1 125 000
Kalahari desert (Africa) 580 000
The Great Sandy Desert (Australia) 414 000
Karakoum (Asia) 350 000
Taklamakan desert (Asia) 344 000
Namib desert (Africa) 310 000
Thar (Asia) 260 000
Of this antarctic and groenland are ruled out..
We can probably use a part of the rest ..
Let's think in terms of eco-dollars.
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pedersendaniel Posted 12:31 am
28 Aug 2008
A 100 MW plant should cover 600-800 acres. This is from a company that constructs these, BrightSource/Luz II
http://www.brightsourceenergy.com/faq.htm, FAQ number 4.
Take 700 acres = 2.8 km^2 for 100MW
100 million watts / 2.8 million m^2 = 35 W/m^2
And this is at the operating plant level, not at the theoretical or research solar panel level.
So for the ~2,000 GW of current electrical power produced in the world today, we would need
2 million MW / 35 MW/km^2 = 60,000 km^2
That's 6 squares, 100 km on a side distributed among the desert areas of the world around the equator.
See Figure 3 in the following by Richard Smalley
http://cohesion.rice.edu/NaturalSciences/Smalley/emplibra ...
vakibs makes an excellent point that eventually all of our energy needs will have to be provided from non-fossil sources. Smalley estimates the current use at equivalent of 220 million barrels of oil per day (2004), or 14.5 terawatts.
According to the CIA 2008 world factbook, the global oil production (2005) was about 80 million barrels per day of oil alone, and 3 trillion cubic meters of natural gas, so those numbers support each other.
In order to supply our western energy use (2 kWh per person per day) to everyone in the world, we would need 60 tW (equal to 900 million bbl per day). 2 kWh per day for 10 billion people.
According to Smalley (quoting Nate Lewis of Caltech), considering 30% energy conversion efficiency of fuels to electricity, these 60 tW of power are equivalent to 20 tW of electricity.
Assuming high solar radiation of 300 W/m^2 and 10% conversion efficiency to electricity (very conservative), we would need less than 700,000 km^2 to provide 20 tW of electrical power. See another map at
http://en.wikipedia.org/wiki/Image:Solar_land_area.png
So to sum up:
60,000 km^2 of current technology solar thermal plants to supply all of the current global electrical production.
Less than 1 million km^2 to provide all of our global energy needs, using very conservative assumptions.
Daniel Pedersen
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GRLCowan Posted 1:06 am
28 Aug 2008
A 100 MW plant should cover 600-800 acres. This is from a company that constructs these, BrightSource/Luz II
http://www.brightsourceenergy.com/faq.htm, FAQ number 4.
Take 700 acres = 2.8 km^2 for 100MW
100 million watts / 2.8 million m^2 = 35 W/m^2
And this is at the operating plant level, not at the theoretical or research solar panel level.
Again, W/m^2 are units of power density, not energy density.
The 100 MW is peak wattage. A well-sited solar power plant that produces 100 peak megawatts will have a year-round average production rate of typically 20 MW, if the Nellis solar power plant is typical.
So Pedersen's 35-W/m^2 translates into 7 W/m^2 in the terms the discussion was previously in.
--- G.R.L. Cowan, H2 energy fan 'til ~1996
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vakibs Posted 2:29 am
28 Aug 2008
I am using energy density and power density interchangeably. This is clearly wrong, but if we average out the power produced during the plant operation and multiply it by the time, we can easily obtain energy density in W-hour/m^2.
Average power is a good indicative of energy density. Not peak power, obviously :) So, let's keep using the term energy density, but let's make a note that we mention average power and not peak power.
@daniel pedersen
Thanks for giving the numbers. The density that you worked out 35 W/m^2 is about twice the number worked out by Dr Mackay. My first question was, were you accounting for night-time ? As GRL Cowan said, we need to average out the power, and use that as the indicative. Dr Mackay refers to Stirling Energy and says it is averaging out at 15 W/m^2. So, I would say GRL Cowan is too pessimistic with his 7 W/m^2. It will be good to iron out the confusion on this value.
If Mackay is right (with 18 W/m^2), we have to double your land estimates. To obtain 2000 GW of current electric production, we will need 12 squares of 10,000 sq-km each.
Also, there will be losses in transmission of electric power (irrespective of how efficient and smart we make our electric grid). The energy density needs to be reworked to account for these losses.
Thanks for also giving the demand based on transport. Mackay has worked out in his blog that the pure electric drive of Rewa GWiz needs about 21 kwh per 100 km. Imagining that we have pure electric drive in future, your figure of 2 kwh per person would let each person drive for about 10 km every day. Quite reasonable, I say. Technology improvements might increase this even further.
General remark
In reality, we have a lot of choices for renewable power. We will diversify into tidal power, CSP, some photovoltaic, some wind and so on. But the energy densities of each of these sources is about the same.. It is quite low. (ranging from 5 W/m^2 to 40 W/m^2). For Jonas and other biomass proponents, the energy density of biomass is about the lowest in all the solar technologies.
We guys are discussing really large amounts of land here. Around a million square kilometers of land dedicated for power production.. it will have a lot of impact on the environment ! (For comparison, this area is twice the size of California). This is not solar panels in the backyard, or 1% the size of deserts. This is much bigger than that. This is where I think is the real bottleneck for renewable power.
But in my opinion, we are not anywhere close to these bottlenecks YET. Growing by the current rate of growth in renewable power, these will not be apparent until atleast another 20 years.
But this doesn't mean we should not plan for the future. Having some allowance for nuclear power makes sense instead of a total renewable plan. How much exactly will be the share of nuclear (whether 20%, 40% or 60%) this needs to be worked out.
It doesn't make sense for nuclear and renewable power industries to be fighting each other. They should work together to get rid of coal.
If we know that there is a need for nuclear power, we should lose no time in getting the technology up to date with safety and environmental issues (a) support breeder reactors which reduce waste (b) increase investment in prototyping these reactors (c) thorough testing of all the safety issues.
These will take time, and we need to do them as early as possible. The argument that nuclear plants take too long to build has been used till now as a criticism. The same argument should work to hasten the support in prototyping and building nuclear plants. Global warming is already upon us. It doesn't matter when we release the CO2 into the air - now or 20 years later. We should do the best possible to get us off the fossil fuels.
Let's think in terms of eco-dollars.
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amazingdrx Posted 3:43 am
28 Aug 2008
With only 50% efficient solar PV/heat congeneration on every suitable roofspace and over every suitable parking lot, and conservation using ground source heating/cooling and plugin hybrids; no more land area would be needed to get all the power we need.
Just the already used land for the buildings and parking would be enough.
That is without biogas from waste, wind, wave, ocean current, standard hydroelectric, river current and so forth. Then there is pumped hydro storage using existing hydroelectric, heat stored in building nass and appliances, and emergency battery backup in homes, and batteries in plugin hybrids.
And super conducting electromagnetic utility scale storage. And of course, the smart grid itself, that adjusts demand to meet supply.
You want to talk energy density problems. talk about radiocative contaminants concentrated in fat cells near human reproductive organs, that energy density is multiplying genetic disease exponentially.
Ok insult boy, do yout worst. I can take it, hehey.
http://amazngdrx.blogharbor.com/blog John Schneider, Northern Wisconsin
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Michael Hoexter Posted 4:19 am
28 Aug 2008
I am using the following data from NREL to make my assertions about the US. In the US we may have more desert area per capita than some nations but a lot less than other nations, particularly in Africa and Australia. "Desert" in the world of CSP is not just the areas that we cordon off in our mind as desert but anywhere with the appropriate "direct normal" insolation for solar thermal plants. In California, where I live, we call certain areas desert but there is much larger semi-arid area that could be used for solar thermal though the power would cost more.
NREL says that there are
212,000 square miles of the US southwest that have more than 6 kWh/m2/day insolation and ground slope of less than 3%. This by no means the entire 6.5 state area but are the prime areas for solar thermal development
NREL assumes a power density of 130MW/sq mile. This is a number that is somewhere between the low estimate of 100MW and higher estimates for more compact plant designs (150 MW/sq mile). With innovation this number should go up.
I assume a capacity factor of .25 in these prime areas, particularly in those areas with over 7 kWh/m2/day.
This yields 285 million kWh/year.
In the electricity sector, the US consumes, inefficiently, 4.1 trillion kWh/year
I'm getting therefore, an area of 14385 square miles or less than 100 by 150 miles.
This is less than 2% of the area of the Southwest (starting in West Texas)
If we, unrealistically, converted all transport inefficiently to electricity and used the same amount of energy we do now (which won't happen with electric motors anyway), we would need an area 45,000 of the 212,000 square miles pointed out by NREL as being suitable (from an environmental standpoint as well) for CSP with storage.
As plug-in and V2G advocates know, battery electric vehicles will be able to piggy back onto the 4.1 trillion kWh/year figure to some degree, leaving the amount of land required to fuel transport at much less than the estimate in "8".
Furthermore, combination renewable power plants, EGS, hydro, wind, solar PV will realistically cover a lot of power usage.
Energy efficiency can cut power usage by over half, so the number I use is 21,000 square miles for all energy use in the US.
I'm not saying that we should plan on building ALL of this capacity. Only that we should start building some of it, get on a technology development curve, etc to start displacing NOW the 50% of electricity generated by coal as well as block the development of new coal plants.
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BILL HANNAHAN Posted 5:14 am
28 Aug 2008
There are four questions that must be answered regarding the grand solar plan.
1 What do the collectors cost?
2 What does the storage equipment cost?
3 What do the transmission lines cost?
4 How do you defend against terrorism?
Here is my comment on the grand solar plan published in Scientific American regarding terrorism.
Imagine it is 2100 and the GSP is fully implemented. You live in a massive high rise apartment building in Atlanta GA.
It is mid July, a massive heat wave is just starting to develop. You wake up early one morning sweating. Your bedroom is abnormally warm, you switch on the light and nothing happens, nothing else works either.
You turn on a battery powered radio and find out that terrorists have dropped all the HVDC power lines crossing the Mississippi river.
As the day wears on outside air temperatures zoom past 100 deg F as does the temperature in your apartment. You drink up all the fluids in your refrigerator.
Where will you and the other 5.000,000 people of Atlanta find safe drinking water?
The GSP will be built over several decades. It takes specialized equipment and a trained construction crew to install a large high voltage power line over water. It will take weeks to assemble the workers, barge cranes and spare parts to replace a power line, and then another week or two to actually install the new line.
So the first line may be up in two to three weeks. What about the other 20 to 30 HVDC lines. There are not enough trained construction workers and equipment to build them in parallel. There are no warehouses filled with cable and towers.
New cable and towers will have to be manufactured. If the manufacturing facilities are east of the Mississippi river their skilled employees are struggling to stay alive, and some of them are loosing the struggle. It will take months or longer to acquire the necessary material to make repairs.
By 2100 the population of the U.S. could be over 400,000,000 and if half live east of the Mississippi that is 200,000,000 people without power during a heat wave.
How many National Guard tanker trucks will it take to provide 200,000,000 people with drinking water, where will the trucks find safe treated water with which to fill up, where will they find fuel or electricity to recharge their batteries?
Think about how slow the response to New Orleans was after Katrina, that is just one medium size city. A meaningful response over the entire eastern half of the country is not possible.
It will require several weeks to restore minimal services, water treatment, waste disposal and minimal food delivery. How will 200,000,000 people survive several weeks of heat wave conditions without these things?
If 99% of them survive, the death toll will be 2,000,000. If 90% survive the death toll will be 20,000,000. If 50% survive the death toll will be 100,000,000.
Things Everybody Should Know About Energy
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amazingdrx Posted 6:04 am
28 Aug 2008
The fact is that only a distributed renewable smart grid can guard against catastrophic outages. Cold can be stored in building mass during off peak times using ground source cooling, eliminating the heat wave induced, transformer melting peak air conditioning loads that are becoming routine in the southwest.
Any central power system, including one that relies on huge CSP installations is vulnerable. Decentralized smart grid generation and storage that facilitates conservation is the way to solve that. And renewable sources are the way to cure GHG climate change and the economic devestation of soaring inflation in fuel based energy sources.
http://amazngdrx.blogharbor.com/blog John Schneider, Northern Wisconsin
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mwright1 Posted 4:33 pm
28 Aug 2008
(Ausra and Prius electric only operation data used --commercial and ready now around the world)
A modern type Solar thermal plant 1 square mile would be in excess of 177MW peak
See the Ausra filing with the California Energy Commission
http://www.energy.ca.gov/sitingcases/carrizo/documents/20 ...
380 Acre field - 177MW plant
http://www.energy.ca.gov/sitingcases/carrizo/index.html
25% capacity factor I accept.
In terms of vehicle drive trains..
A Siemens Combino Tram (Victoria Australia) caries 190 people using 153kwh of electricity per 100km
While a Nissan Patrol (or most other SUV 4WDs) uses 173 kwh to carry 5 people 100km
Lets say Electric Drive train for Tram/Train is 40x less primary energy.
And for cars
My father's Toyota Plug-in hybrid Electric gets 160watt hours per km, average across all driving conditions. This is a mass production car with a minor modification. That is 16kwh per 100km
An Average USA / Australian car gets 111kwh (electricity equivalent) per 100km, but that doesn't include total life cycle 140kwh per 100km is the correct figure.
A modest plug-in hybrid prius conversion (5kwh battery bank) would give 40km range accounting for 80% of total kilometres traveled.
This accounts to around 1/9th the electricity required versus the energy from burning fossil fuels in the Petroleum extraction/distribution/cracking/internal combustion engine drive system.
Which of course is far more complicated than the Smart Grid / Solar Thermal / Wind Power slow charging Electric drive train.
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vakibs Posted 5:13 pm
28 Aug 2008
I have given an entire list of numbers. Do you want to dispute on any numbers I mentioned ? Then, find the hard numbers. And tell me where my conclusions are wrong.
With only 50% efficient solar PV/heat congeneration on every suitable roofspace and over every suitable parking lot
For example, here you can mention what is the energy density of the 50% solar PV that you talked about. Then you can mention the hard data about the total available roofspace and parking space. Then you mention your assumptions on incoming solar radiation. Then a simple multiplication will produce the amount of power that can be generated with this technology. We will then see how big that is supposed to be. Unless you show the numbers, I can't discuss with you.
You should do the same with every other energy source you are talking about. Just because you are lazy to do all this, it doesn't mean we have to gulp your arguments down our throat.
These concerns are a lot more valid than your hypothetic concerns about terrorists hitting a nuclear plant. And yes, there are proven safety mechanisms for such a scenario.
Unlike you, Michael and Daniel have produced a decent list of their estimates. Now we can have a meaningful discussion there.
Let's think in terms of eco-dollars.
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vakibs Posted 6:47 pm
28 Aug 2008
"Desert" in the world of CSP is not just the areas that we cordon off in our mind as desert but anywhere with the appropriate "direct normal" insolation for solar thermal plants.
In my understanding, a "desert" is a place where we can do the least harm to biodiversity. A power plant occupying such a place will have an impact on the ecosystem (as one user "stopgreenpath" would point out to you) but this impact will be less than in any other place. I hope your new definition of "desert" would satisfy this as well ..?
# 212,000 square miles of the US southwest that have more than 6 kWh/m2/day insolation and ground slope of less than 3%. This by no means the entire 6.5 state area but are the prime areas for solar thermal development
212,000 sq miles = 549,077 sq km (1.4 times the size of California).
Insolation of 6 kwh/day/m^2 = 6000/24 = 250 W/m^2 . An optimistic number for a temperate region, but you can definitely find a few places with such insolation.
# NREL assumes a power density of 130MW/sq mile. This is a number that is somewhere between the low estimate of 100MW and higher estimates for more compact plant designs (150 MW/sq mile). With innovation this number should go up.
Power density of 130 MW/sq-mile = 130*10^6/2589 988 W/m^2 = 50 W/m^2. This is clearly peak power density. You should average this out to account for night time and cloudy days (to truely reflect the solar insolation at that region). The revised number will be around 15 W/m^2 to 18 W/m^2. Please get back to me with comments on this. (as requested in the remarks section)
# I assume a capacity factor of .25 in these prime areas, particularly in those areas with over 7 kWh/m2/day.
Is the capacity factor a way of averaging out power. In that case 0.25 * 50 = 12.5 W/m^2 which will be a pessimistic estimate. Does this capacity factor also include transmission losses ?
# This yields 285 million kWh/year.
I lost the train here. What yields 285 million KWH/year ? A plant spread over 1 sq-mile ? That is not correct.
With your numbers, I find that with a wattage of 130 MW * 0.25 = 32.5 converted in kwh/yr (32.5 *365/24) = 494 million kwh/year.
Please explain, and calculate your numbers here.
# In the electricity sector, the US consumes, inefficiently, 4.1 trillion kWh/year
# I'm getting therefore, an area of 14385 square miles or less than 100 by 150 miles.
First question, is 4.1 trillion KWH/year the total electricity consumption, or just home electricity consumption ?
4.1 trillions = 4.1 * 10^6 millions
Divided by your mysterious number of 285, we get 4.1 * 10^6 / 285 = 14385 sq miles.
So that is true, your earlier number is the total power produced by a power plant spread over 1 sq-mile.
By the way 14385 sq miles = 37,256 sq km = 3 squares of 100X100 km each.
# This is less than 2% of the area of the Southwest (starting in West Texas)
# If we, unrealistically, converted all transport inefficiently to electricity and used the same amount of energy we do now (which won't happen with electric motors anyway), we would need an area 45,000 of the 212,000 square miles pointed out by NREL as being suitable (from an environmental standpoint as well) for CSP with storage.
Do you mean to say that the total US transport needs are 45000*285 = 12.8 trillion kwh/year ? Divided by US population (301,139,947) and the number of days in the year (365) we obtain 116 kwh/person/day. This can be slashed to 1/3rd or even lower.
# As plug-in and V2G advocates know, battery electric vehicles will be able to piggy back onto the 4.1 trillion kWh/year figure to some degree, leaving the amount of land required to fuel transport at much less than the estimate in "8".
I agree with you, but let's not say "some degree". Let's calculate exactly to which degree.
# Furthermore, combination renewable power plants, EGS, hydro, wind, solar PV will realistically cover a lot of power usage.
Each of these modes of energy production will require about the same amount of land as CSP. Their energy densities are at about the same level.
# Energy efficiency can cut power usage by over half, so the number I use is 21,000 square miles for all energy use in the US.
21000 sq miles = 54389 sq km. This looks quite low for me to be true.
My remarks
The key number for your whole argument is the energy output of a CSP plant covering 1 sq-mile : you say this is 285 million kwh/year. Please rework this and show your assumptions behind it.
Particularly, it will be really helpful if you mention the average density you assume for CSP (my calculations showed you are using peak power of 50 W/m^2 which is not correct to use).
We need transmission cables to send all the power that is produced in the southwest to everywhere else in the USA. You haven't worked out the losses in electricity over the transmission.
Your estimates for other energy demands are incomplete. We also need to account for energy demands for food, fertilizer and imported gadgets.
Let's think in terms of eco-dollars.
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vakibs Posted 7:14 pm
28 Aug 2008
380 Acre field - 177MW plant
http://www.energy.ca.gov/sitingcases/carrizo/index.html
380 acres = 1 537 805.44 sq meters
The peak power density you mentioned = 115.1 W/m^2
With your capacity factor of 25%, we adjust this to 28.7 W/m^2. This is abnormally high. (energy density worked by real statistics of a plant in operation is about 15 W/m^2. Either your capacity factor is not indicative of the true solar insolation, or there are other assumptions that you didn't mention.
It will be good to have the true statistics of the Ausra plant in operation (instead of some theoretic value). This is exactly what GRL Cowan has asked for.
Also, you should account for transmission losses. These losses will further reduce the energy density in practice.
By the way, I agree with your conclusion that pure electric drive might reduce the energy usage by 1/9th of the ICE engine.
Let's think in terms of eco-dollars.
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amazingdrx Posted 10:49 pm
28 Aug 2008
Figure away, but your basic assumptions the figures are based on are the problem.
Mine are based on actual studies of real roof space suitable for solar power, actual savings from ground source heating/cooling, actual energy conservation acomplished by home owners, and real smart grid technology being developed by Xcel.
Long calculations of solar insolation and capacity factor and ever increasing electric power demand tend to skew the picture in the direction of unlimited, cheap nuclear power. A dangerous imaginary construct. Evidently a picture Obama is starting to buy into.
http://amazngdrx.blogharbor.com/blog John Schneider, Northern Wisconsin
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vakibs Posted 11:53 pm
28 Aug 2008
I am happy that Obama is not listening to Amory Lovins and his gang. We need a responsible energy strategy, and not one driven by blind prejudice.
Bill Hannahan is questioning you on the constraints of construction cost, material cost, reliability and so on. None of these issues are completely proven for renewable power (I wish they were, but they are not).
But my concern on renewable power is something even more basic. I say let's ignore the dollar costs.
I am just concerned about the true environmental costs (how much mining we need to do, how much waste is generated, what are the water requirements and land requirements etc). All these questions come down to the basic issue of the average energy density of different renewable technologies. When a serious article like Michael's appears on grist without even mentioning energy density, there is something seriously wrong. Misleading facts such as 1% of the desert area is sufficient will fool people into thinking that land is not an issue. (Until Michael's explanation, I didn't even know what he meant by a "desert")
As being worked out by Michael, Daniel and me, the land requirements for CSP are in the range of 50,000 sq-km. This is not a joke, even for a vast country like the USA. Mammoth construction of this level will require enormous amounts of capital, and it will have a huge environmental impact. Why don't we be open about this ? For more densely populated countries in Europe and Asia, this land will be even further a constraint. Are we serious about reducing the use of coal in China and India, or are we not ?
Energy densities of solar technologies are open facts, let's remove the confusion there and discuss clearly. Getting satisfactory answers for these questions is an important priority for environmentalism. Let's not shoot ourselves in the foot and end up burning coal even after 20 years.
No matter how much energy demand is reduced in the USA, the global energy demand is going to rise more and more. We need to be prepared for generating this much of energy, in the smartest manner possible. My order of preference is (a) energy conservation and efficiency (b) renewable technologies as long as they are not harming biodiversity (c) fourth generation nuclear power.
If you consider me a "nuker", so be it. But I am not the only one in the environmentalist community.
Let's think in terms of eco-dollars.
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amazingdrx Posted 12:14 am
29 Aug 2008
Google is big on geothermal for instance, but ignores the obvious play. Smart grid control and billing hardware and software.
Distributed renewable smart grid technology is new, but Xcel energy, a huge corporation understands it and is taking the lead in this area.
Once they pioneer and prove it is the best way to proceed, large institutional investors will be pushing each other out of the way to throw their money into it. Buy Xcel and the companies actually manufacturing the smart grid hardware. There maybe software plays too.
If you want to own the Dell and MSFTs of this renewable energy boom, buy soon. Sell into the boom, when large investors are hungry for all the shares they can get.
Oil war winding down, with a crushing blow to the obvious group in rural Pakistan, will signal an economic upturn with renewed business, investor, and consumer confidence. Obama will win with this strategy. And then we all win.
Sorry for the nuker remark, but this technology is dangerous and completely unecessary, it needs to be outed for what it really is. Obama has received some bad advice in this area.
http://amazngdrx.blogharbor.com/blog John Schneider, Northern Wisconsin
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pedersendaniel Posted 8:58 am
30 Aug 2008
1- how much solar radiation is there?
2- how much of it can be converted into electricity?
How much solar radiation is available?
According to a number of sources, I think that we can agree that 250 W/m^2 is a reasonable power density for a desert area, averaged continuously over day and night for a year or more. That's ~2200 kWh per year per m^2. I've seen estimates for long term averages of 260 and 270 W/m^2 (taking into account day and night and seasons).
Conversion Efficiency:
According to Science Daily News (February 2008), "Sandia National Laboratories and Stirling Energy Systems (SES) set a new solar-to-grid system conversion efficiency record by achieving a 31.25 percent net efficiency rate."
"The conversion efficiency is calculated by measuring the net energy delivered to the grid and dividing it by the solar energy hitting the dish mirrors. Auxiliary loads, such as water pumps, computers and tracking motors, are accounted for in the net power measurement."
That's SOLAR TO GRID efficiency of 30%, so it represents the amount available to the electrical grid from incoming sunlight.
I've read that concentrating solar power systems have over 20% conversion efficiency. (Does anyone have a source for this?)
So if we take the lower end of 15% conversion efficiency, and multiply it by the long term average of solar radiation of 250 W/m^2 in desert areas, we get something near 35W/m^2.
For 10% efficiency we get 25 W/m^2.
This is the long term average power density, accounting for nighttime and seasons, and does not yet account for transmission of electric power.
So, what am I missing?
Daniel Pedersen
Links: available solar energy, Union of Concerned Scientists
http://www.ucsusa.org/clean_energy/technology_and_impacts ...
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mwright1 Posted 6:18 pm
30 Aug 2008
28.7W /m^2 reasonable.
The thing with the sterling plant which is tiny is that unlike a Compact Linear Fresnel plant it has overshadowing issues, so the density is less. By using linear fresnel mirrors this problem is significantly overcome.
The Ausra figures are based on REAL FIGURES from an operational plant at Liddell Power Station in New South Wales Australia
http://www.ausramediaroom.com/common/images/gallery/Ausra ...(62)_L.jpg
http://www.ausramediaroom.com/images.php
If you want to understand how you could run the USA economy on Solar thermal then read this peer reviewed paper.
http://www.ausra.com/pdfs/ausra_usgridsupply.pdf
Criticise this paper - by a real solar scientist with a real company, which is about to be worth Billions.
Also - I have no problem with a combination of these big solar centralised power plants in conjunction with rooftop PV. Big Solar plants lend themselves to storage including Ammonia Thermochemical Disassociation, which is as high as 97% efficient way of storing Thermal energy for dispatch at night. See
http://solar-thermal.anu.edu.au/high_temp/thermochem/inde ...
I have visited these facilities and interviewed these world leading solar experts. So I give you this information to consider first hand.
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mwright1 Posted 6:26 pm
30 Aug 2008
http://www.ausra.com/pdfs/ausra_usgridsupply.pdf
(The guys who can do the Solar Thermal maths) - hence why they are actually doing the numbers and building the plants
The U.S. national vehicle fleet-miles travelled were 1.0 x 1013 in 2005/615. Battery electric vehicles typically use between 0.17 and 0.37 kWhe per mile, so for 1.0 x 10^13 miles of vehicular travel the US would need 1.7-3.7 x 10^6 GWh to fully eliminate vehicle emissions from fuel use. In this thought experiment, national solar generation would consequently have to climb by 42% - 91% to accommodate an entirely electrified vehicle fleet. The land area requirement for
the supporting CLFR generation plant would climb to between 182 and 211 km on a side. Superimposed on our electricity load ...
http://www.ausra.com/pdfs/ausra_usgridsupply.pdf
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Pangolin Posted 7:12 pm
30 Aug 2008
I know one well-sited guy who recieves a check every month from a windmill 50 yards from his house. His windmill at full speed is a lot quieter than the hospital three blocks from me.
Every state in the union has net-zero buildings in existence right now. Simply assuming that we are going to make no progress towards an obviously achievable goal is crap.
The local brewery has solar panels covering the employee parking lot the lucky bastards. Those are prime parking spaces on days like last week when it was 110º F. Lots of people were biking around town yesterday too.
It's fairly easy to say that about 3/4's of the current energy used by our civilization is wasted. The exact same job could be done for less energy or even better could yield a net gain while achieving the same result.
Rooftop solar panels reduce cooling loads while powering air conditioning or geoexchange heat pumps. Wind power produces the most power in northern climates precisely when wind chill would increase the input required to allow the same systems to heat houses. The windbreak or shade tree planted to condition the house environment provides biomass that can be gassed via methane fermentation or pyrolisis and the byproducts returned as fertilizer.
The one think nuclear power advocates never do is assume that a good quality of life can be had using less power. They can't do this even if you can prove that somebody else has already done it. Sacramento did that closing it's expensive Rancho Seco plant and through conservation and aggressive alternative energy programs now produces more alternative energy as a percentage while its population grew while keeping rates below PG&E which was saddled with the expensive Diablo Canyon plant.
The math is that conservation, solar, wind and geothermal are cheaper than nukes and can get installed faster and cleaner without paving the planet.
Put the Carbon Back
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Jon Rynn Posted 5:02 am
31 Aug 2008
The US car fleet travels about 3 trillion miles, total, so if you get 1 mile per 1/3rd kwhr, you would need another 1,000 billion kwhrs, or an increase of about 25%. However, some percentage of that is composed of people going way overe 40 miles per day (the range of an electric vehicle), so there's no way to keep those vehicles going.
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vakibs Posted 12:01 am
01 Sep 2008
So if we take the lower end of 15% conversion efficiency, and multiply it by the long term average of solar radiation of 250 W/m^2 in desert areas, we get something near 35W/m^2.
For 10% efficiency we get 25 W/m^2.
This is the long term average power density, accounting for nighttime and seasons, and does not yet account for transmission of electric power.
So, what am I missing?
What you are missing here is that your efficiency numbers (20% or 10%) are of the equipment that is converting solar energy to electricity. Now, for CSP, the parabolic mirrors have a lot of free space in between them. This is needed for manipulating the mirrors to orient towards the sun. The solar energy that falls on this free space is essentially lost.
If you take the total land area of the power plant (and not just the land used by the equipment) you will get a reduced energy density. 15 W/m^2 to 18 W/m^2 is indeed an apt number for CSP technology.
@mwright .. @jon
Thanks for all the links. Ausra is apparently cited at some place, demanding a land area of 153 X 153 sq km for satisfying the current US electricity demand. This will lead to an energy density of 18 W/m^2 (quoted from page 200 of Dr. Mackay's book : he has been looking at Ausra).
Your numbers on transport are also very good. Jon agrees with you here. The electricity demand might increase by 25% when transport is electrified completely. So this would require a bigger square of 182 X 182 sq km or 211 X 211 sq km. (40,000 sq km).
A comparison of this number : the yellowstone national park in the USA has a size of 8983 sq km. What we are demanding here is an area of 4 yellowstone parks.
Construction on this mammoth level will need a lot of material : whose costs are going upwards recently. A lot of material needs to be mined.
Another interesting requirement would be the amount of energy required for this construction : whether this energy should be supplied in the form of electricity or gasolene.
And most importantly, the environmental impact due to this mining and construction needs to be evaluated.
@pangolin
It's fairly easy to say that about 3/4's of the current energy used by our civilization is wasted.
I don't agree with you there. By improving efficiency, we might conserve a 1/3 or a maximum of 1/2 of the electricity. Not more than that. No matter how smart you make the electric appliances and grid, some electricity will always be wasted.
Rooftop solar panels reduce cooling loads while powering air conditioning or geoexchange heat pumps.
No, let's not argue like this. Let's exactly work out how much energy can be produced by rooftops solar panels. Then let's work out how much energy demand is from air conditioning etc.. When we have hard numbers, they can be compared against each other.
And these problems will not be solved overnight. The wastage of electricity is just a symptom of a deeper problem, which is a culture which encourages waste (including food waste).
Let's think in terms of eco-dollars.
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mwright1 Posted 10:30 am
01 Sep 2008
http://solar1.mech.unsw.edu.au/glm/papers/Mills_projectpr ...
For 5MW 11 hectares of land
Steel 220 tonnes
Glass 27 tonnes
Concrete 320 cubic metres
**very conservative figures as this is pre the Ausra venture capital injection -- now they're concentrating on doing things very efficiently.
92 miles 23287 hectares.
So multiply the below figures by 2328
512160 tonnes of steel
62856 tonnes of glass
744960 tonnes of concrete.
In the USA 10 million vehicles are sold each year representing 12 million tonnes of steel
BHP has a plant in Australia that produces 5 million tonnes of steel.
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mwright1 Posted 11:12 am
01 Sep 2008
which is
2 192 165 hectares
199287 is the multiplier
43 million tonnes of steel
or more like 4 years of US vehicle manufacturing
Someone else can check the figures if they like
I think the resources for 4 years of vehicle production is pretty decent to repower the united states with renewables and provide for most vehicle propulsion.
Note: this will also displace a massive amount of steel required for Tankers / Oil refining / drilling.
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mwright1 Posted 2:13 pm
01 Sep 2008
to reduce the size of the power system even further I propose.
80% Rail - electric train /tram for passengers / freight
20% PHEV and pure EV
Targeting a 66% reduction in average vehicle miles (kilometres) travelled per car for the US fleet.
Pushing road maintenance (resurfacing etc) out from a 14 year cycle to a 42 year cycle.
hence we would achieve a 96% reduction in liquid fuel requirement based on 40km 5kwh PHEV battery.
AND The electric drive train in well utilised public transport trams /trains would be about 1/40th the electricity of a car
or 1/4 the electricity of a PHEV and no liquid fuels requirement..
Also check out my draft presentation I give which gives some background.
http://beyondzeroemissions.org/files/BeyondZero-slideshow ...
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Jon Rynn Posted 2:20 am
02 Sep 2008
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mwright1 Posted 2:56 pm
03 Sep 2008
That Charging our cars from the Grid using smart meters adds supply security for those real time electrical requirements.
And that direct Solar PV and Wind which are more variable can be backed up by Solar Thermal + storage (ammonia thermochemical etc)
So I guess that leaves us with a 30-50% EE reduction target across all sectors of the economy. To really get the total price of the change over down.
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vakibs Posted 6:38 pm
03 Sep 2008
No Nuclear -- Yes Solar All agreed?
What we agreed on are the requirements of a pure solar economy. But this doesn't mean we have agreed on the optimal decision for our energy needs.
I consider solar energy as a possible and a viable choice. (Thank you for the analysis on the steel and other material that needs to be mined for the grand CSP plan.) But I do not yet consider it to be my optimal choice as to eliminate nuclear altogether from the table.
I will give you two comparisons :
(1) USA can replace all its gasolene needs by growing cellulosic ethanol plants. The agricultural land that is present in USA will be "sufficient" for obtaining this. But does it mean this is the optimum way of running the transport sector ?
(2) Obtaining Hydrogen from water electrolysis and running vehicles on this Hydrogen will give you a mileage equivalent of less than $4 gasolene. Now that gasolene prices are higher, this technology has become economically feasible. But does it mean this is the optimum way of running the transport sector ?
None of the above two alternatives are correct. You have written (and I agree) that most of the transport sector should use electric drive (light rail + trains + PHEVs). This is the optimum way of running transport, with the technology that we have. What was our criteria for optimization ? Minimal energy use.
Now, for producing our required energy, we have not yet mentioned our criteria of optimization. My criteria for optimization is "minimal environmental impact" with respect to land, water use and impact on biodiversity. I would like to minimize the territorial space on which humans impact the environment. I would like to leave the maximum possible land for plant and animal species in a natural ecosystem.
With this criteria, I would welcome solar technology in different forms (a) solar panels on all the available roof space (b) wind mills spread over agricultural land (c) small hydro-electric plants which do not require large reservoirs (d) tidal plants close to the ocean shore, but where there is no marine life (e) solar CSP plants in areas with no biodiversity. (f) biomass obtained by responsible forestry ... and so on..
Beyond that, I would like to use nuclear energy for the rest of our growing energy needs. This is because its requirements on land are a thousand times smaller than the solar equivalent. (Its power density is around 1000 W/m^2).
Your criteria of optimization could be different from mine : "no accidantal radiation spill" or "no proliferation" could be one of your optimization criteria. In which case, you can eliminate nuclear from the mixture altogether.
This is the debate we need to have : on what are our criteria for optimality.
As environmentalists, what worries us most are the environmental costs. This should be one of our criteria for optimality. We have not analyzed in detail the environmental costs of this construction and operation of neither nuclear plants nor solar plants. So, let's work towards doing that.
Let's think in terms of eco-dollars.
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hapa Posted 8:40 pm
03 Sep 2008
(2) would you like to share it with your neighbors?
(3) would you like us to share it with your neighbors? they may not enjoy us sharing it only with you.
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mwright1 Posted 8:42 am
05 Sep 2008
You claim that Nuclear power uses a small amount of area.
However an incomplete Total life cycle analysis on the Nuclear Life Cycle shows that more land was used in Australia for Nuclear development than would be required to power the world on Ausra CLFR Solar Thermal power plants.
Testing of the effects of Nuclear radiation on People and the Environment -- important background knowledge /risk management was performed at the Woomera Rocket range.
http://homepage.powerup.com.au/~woomera/map.htm
As you can see the area covered would provide enough energy for the world's gross energy needs.
That's without taking into account
Heat Pumps
Electric Drive Train Total life cycle
Insulation
Other EE
As for the mines in real time.
The Ranger Uranium Mine, one of the world's biggest. Which has an output of 1/4 of the USA annual requirement sits on 7680hectares
This doesn't complete the story... Because deliberate and accidental releases from the tailings damn contaminate an area of at least 400 square kilometres.
The Rum Jungle Mine (now decomissioned) has contaminated over 100square kilometres of land, and is a no go zone.
Please provide the numbers to backup your claim on
the nuclear life cycle being less damaging that solar thermal. Given that the main material inputs can be obtained from a few years of US auto sales, or less than 1 year worth of global auto sales. (For the USA - the world's biggest electricity and petroleum consumer to convert over)
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mwright1 Posted 9:00 am
05 Sep 2008
Hi Vakibs,
While I'm trying to paint a picture of total life cycle, Olympic Dam Uranium mine is the largest industrial user of Ground Water in the Southern Hemisphere 35 Megalitres per day.
The expansion of Olympic Dam will use upto an additional 125 Megalitres per day.
Unlike Air Cooled Solar thermal plants (Like Ausra's which will use 1 domestic swimming pool worth of water per day) or Solar photovoltaics a huge amount of cooling water is required for Nuclear Power plants.
During the heat wave in Europe, French Nuclear power plants kept breaching there conditions and releasing over limit hot water into water ways. compromising those ecosystems.
In July and August 123
French nuclear workers contaminated - 4 Plants malfunctioned - 126 workers contaminated in 15 days
http://uk.reuters.com/article/oilRpt/idUKL246508502008072 ...
So with available numbers. (if you can improve the quality of the data and show us the numbers it would be good). It seems Nuclear doesn't stack up and the following renewable options do
Benign Solar thermal with storage (Security of supply)
Smart meters (Security of supply - transportation)
Fixed Rail (trams and Trains) 80% trips urban, 50% trips rural
PHEV and Pure EV 20% trips urban, 50% rural
Insulation, Heat Pumps and Rooftop Solar PV
End use demand reduction
Taxes to tax low quality products and then subsidise the better performing products, to cause rubbish to fall out of the market.
Reduction in end use water 3/4.5 litre toilets with pre use of cistern water to wash hands
Low flow 7.5L per minute showers.
Reduces Pumping requirements water storage requirements.
Zero Carbon houses (UK policy 2016 - austin TX policy -- Passiv Haus standard europe)
Biofuels from Algae -can be produced at City Sewerage plants 50,000 litres per hectare for residual fuel requirement. AND crop residuals pyrolysis - syngas reformed to methanol for farming machinery.
And the list goes on - commercial and available now
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mwright1 Posted 9:04 am
05 Sep 2008
Also I agree with you on wind.. it's cheap so you build as much as you can, do a statistical analysis across Wind and Solar availability in large geographically diverse links (sured up by HVDC electrical transmission). And the use of smart meters to minimise the load matching required during the rarer low solar incidence low wind events
And then work out how much solar thermal with storage is required for the estimated 5-15% of annual dispatchable power requirement that is needed to maintain supply security.
Unfortunately ocean wave, tidal, current technologies that are relatively environmentally benign are not yet commercial like solar thermal and wind power technologies.
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