Comments rmcleod has made
SSPS
If I may, I wrote an article on this in 2006:
http://entropyproduction.blogspot.com/2006/07/solar-power ...
I'm guessing that's a trillion measured in 1970s dollars.
-- entropyproduction.blogspot.com
On Can we shoot concentrated solar power down from space? posted 1 year, 5 months ago 18 ResponsesCCS Wedge
CCS works from the point of view that it will prevent any new coal plants from being constructed, since they won't be cost competitive.
-- entropyproduction.blogspot.com
On Preventing dirty coal plants is the most urgent climate policy posted 1 year, 6 months ago 7 Responses'Inflection' not 'Inflexion' Point
nm
P.S. People are still buying Chrysler-brand cars? Aren't they 'operationally' bankrupt?
-- entropyproduction.blogspot.com
On March small car sales up; SUV, truck sales down posted 1 year, 7 months ago 4 ResponsesDollar Pegs
This is part and parcel of the failing US dollar, but when countries peg their currency to the dollar even if they have a trade surplus with the USA then they are explicitly importing inflation.
-- entropyproduction.blogspot.com
On What's causing the sudden run-up in food prices? posted 1 year, 7 months ago 39 ResponsesRetail Electricity Costs
Nanosolar being sold out for a year isn't really a good argument against residential installations. When you factor in connection fees, transmission fees, etc., residential electricity may be the most expensive source of power around. I personally pay around 60 cents/kWh when you add in all the fixed costs. If I was to go off-grid, I could pay-back possibly faster than if I had a net-metering system, simply because 50 cents is the fixed fees and 10 cents is the marginal price.
Similarly a commercial consumer (like Walmart) likely pays different fees for electricity depending on the time of day. Now, typically PV power output peaks a couple of hours before peak demand, but the correlation is still fairly strong.
It's simply demand outstripping supply, and it's the primary reason the price of PV hasn't dropped even as the thin-film manufacturers have reduced their costs. I think it's more likely that Nanosolar just wants to keep their marketing cost in check while they get their manufacturing operations going.
-- entropyproduction.blogspot.com
On For Nanosolar, the future is municipal solar power plants posted 1 year, 7 months ago 10 ResponsesCross-pollination for the Weeds
You have to wonder if some of this isn't just cross-pollination from crop to weed introducing the genetic resistance to pesticides. Canola, in particular, is basically a variety of mustard weed.
-- entropyproduction.blogspot.com
On While global GMO acreage surges, herbicide-resistent weeds thrive posted 1 year, 9 months ago 29 ResponsesPressure
Don't underestimate the value of the continual pressure such a significant media event of the release of 'another' IPCC report has. It takes a long time to change the consensus of the people of the world. I would say, relative to other shifts such as the suffrage movement, the move on climate change is actually occurring at something approaching 'ludicrous' speed.
It wasn't so long ago that the corporate media sought out a climate contrarian to 'balance' their article. I'm not noticing that so much anymore. Since 2000 we've moved from indifference to, "CO2 doesn't warm the atmosphere," to, "human's aren't warming the atmosphere," to, "it's too expensive to fix."
-- entropyproduction.blogspot.com
On It is doubtful that future IPCC reports will make a difference in climate policy posted 1 year, 11 months ago 9 ResponsesEthics
This would seem to cross the boundaries of ethical animal testing in science. I mean, the rats will die, it's not like they are going to be returned to earth. We already put humans in space for half a year, so what is this month-long experiment going to tell us that will help save human lives? I doubt this would get past any ethics review board at a university or research hospital.
Like so much NASA's human spaceflight program does, this seems to be on the same intellectual level as the baking soda and vinegar volcano at a high-school science fair.
-- entropyproduction.blogspot.com
On NASA has bold plans to ... send rodents into orbit posted 1 year, 11 months ago 12 ResponsesIGCC Numbers
Nucbuddy:
You are mis-reading that particular section, and it's thermodynamically impossible anyway.
Look up in the heading "Storage & sequestration of CO2":
"Currently IGCC plants have a 45% thermal efficiency."
That 45 % figure is without the energy cost for sequestration, which, as the article discusses, is currently very high (and frankly not likely to decline as much as they would like). I have some grave doubts regarding some of the numbers that article throws around with regards to sequestration numbers, I would have to check the sources. I suspect they aren't based on real-world tests.
The 73 % figure you list is simply for the gasification of the pyrolyzed coal to carbon monoxide and hydrogen and then a pure hydrogen stream. It covers the liquid oxygen plant, etc., not the combustion of the hydrogen. By my reading it does not cover the pyrolysis (i.e. burning off the hydrogen in the coal to be left with coke) either.
They seem to be implying that the efficiency of burning hydrogen is 73 % / 60 % = 82%!!! I know of no thermal cycle that achieves 82 % efficiency. It's likely past Carnot cycle theoretical limits, or the Gibb's free energy formulation of the same for fuel cells.
-- entropyproduction.blogspot.com
On The cost of the FutureGen 'clean coal' plant doubles posted 2 years ago 16 ResponsesEgad
Consider the obvious with regards to photovoltaics: no fuel costs.
For the clean coal plant, 1 kW at 75 % capacity factor for a year is 31.5 GJ of energy. Coal is about 21 GJ/short ton, or at 30 % burning efficiency produces 6.4 GJ electricity/ton. Say $40/ton for bituminous stuff. That works out to about $200 per year per kW of electrical capacity, just in the cost of coal. Personal and maintenance are on top of that, let's say double.
Everyone knows that PV is front-loaded in the capital costs. It's just they work for 25 years, guaranteed. As long as the contacts don't corrode out, they should still be working in forty years.
Given the above numbers, over the cource of 25-years, PV is $22,500/kW delivered (capital divided by capacity factor $4500 / 0.2 [/kW]).
If we consider coal maintenance roughly double fuel, or $400/kW then over 25-years of operation that 'clean coal' plant will require ($6500 + $400/year*25year) / 0.75 [/kW] = $22,000/kW.
That's basically saying that only the cost of borrowing money is putting 'clean coal' ahead of PV, and we're not assigning coal any future liabilities.
If this is the 'future of coal', then coal has no future.
-- entropyproduction.blogspot.com
On The cost of the FutureGen 'clean coal' plant doubles posted 2 years ago 16 ResponsesMore than Nuclear
Wow, that's a huge capital cost -- much more than nuclear. I think I'd rather deal with solid nuclear waste than sequestered CO2 as well.
Compared to solar, you could certainly get more nameplate capacity for less. Solar is still around 4500 $/kW. The drawback is the 20 % capacity factor compared to perhaps 75 % for coal. The benefit is no fuel costs, trivial maintenance, and no unaccounted liabilities.
This does seem to suggest that advocating coal with sequestration is a great way to improve the market penetration of renewable energy sources.
-- entropyproduction.blogspot.com
On The cost of the FutureGen 'clean coal' plant doubles posted 2 years ago 16 ResponsesHuman Spaceflight
The human spaceflight program has indeed been a giant waste of money. Effectively now it is simply a job welfare program for aerospace engineers. The USA still graduates too many aerospace engineers as a legacy of the cold war. NASA needs to cut lose the astronauts and get back to doing science. What we have now is a soul-deadening bureaucracy with no apatite for risk taking. "Failure is not an option," is indeed a truism when anyone who dares is ostracized.
The idea that the human spaceflight program has contributed anything of use to the general body of scientific knowledge is an urban legend. NASA didn't develop computer technology, lasers, or anything of the sort. They didn't even develop Tang or Velcro. Perhaps people are confusing NASA with N.A.C.A., its predecessor, which did good work in aerodynamics and rocket technology. Current NASA seems to think you can make orbital launch cheaper by building more and more complex machines. Stick to the robots.
Scare tactics like the prospect of 'asteroid' collision are just that. The latest estimate for the 'dinosaur killer' was that it took 100 million years between the collision in the asteroid belt and the one with Earth:
http://www.nature.com/nature/journal/v449/n7158/full/4490 ...
Think about it, the debris had to pass across the Earth's orbit millions of times before a collision occurred. Worrying about this sort of thing is not cost effective from a risk-reward point of view.
-- entropyproduction.blogspot.com
On Moon base project sucks up potential climate research dollars posted 2 years, 2 months ago 10 ResponsesOld Tech, New Results
Magnetic refrigeration has been around since the 1950s, but it's only use was for working below liquid helium temperatures (4 Kelvin). The advance here is that they are using permanent rare earth magnets instead of superconducting electromagnets (which require cooling).
http://en.wikipedia.org/wiki/Magnetic_refrigeration
Claims that this process is much more efficient than a compression refrigerator are not on the strongest thermodynamics ground.
I don't think I would want one of these in my house. The magnetic fields required would really mess up a lot of electronic equipment.
-- entropyproduction.blogspot.com
On Magnetic cooling tech hits a milestone posted 2 years, 3 months ago 3 ResponsesSilly Hype
I posted on this in July:
http://entropyproduction.blogspot.com/2007/06/aluminium-h ...
It's a terrible idea.
Some highlights:
- 2/3rds of the energy in the aluminium is wasted as low-grade heat, 1/3rd goes towards producing hydrogen.
- A car would require about $160,000 worth of Gallium metal.
- It's not very clear how you would be able to control the reaction rate, and thus it is not able to produce hydrogen on demand.
-- entropyproduction.blogspot.com
On Interesting hydrogen-generating technology from Purdue posted 2 years, 3 months ago 14 Responses- 2/3rds of the energy in the aluminium is wasted as low-grade heat, 1/3rd goes towards producing hydrogen.
Organic PV by Another Name
This is, basically, very very similar to heterojunction organic photovoltaics. Titanium Dioxide (white paint) has a fairly big electronic bandgap so it only really absorbs blue light and lets infra-red and red pass through. The dye molecules are quite vulnerable to damage from ultraviolet light, being organic and all and the efficiency likely is quite poor (% 5 would be impressive).
-- entropyproduction.blogspot.com
On Not any more posted 2 years, 3 months ago 6 ResponsesClassic NIMBY
I love when he's trying to see the windfarm in the simulated image of the view on the laptop.
-- entropyproduction.blogspot.com
On Watch a video outlining the conflict over this wind farm posted 2 years, 3 months ago 7 ResponsesSolar Energy Payback
Typical energy payback period less than 3 years:
http://entropyproduction.blogspot.com/2006/05/solar-payba ...
Efficiency standards are usually under the Air-Mass 1.0 standard, which is basically 1000 W/m^2 at 25 ^C:
http://entropyproduction.blogspot.com/2005/08/air-mass-15 ...
Most systems that achieve super-high efficiency are tiny (less electrical losses) and use concentrating optics (which do not work so well in the presence of clouds). As such, they are laboratory results.
-- entropyproduction.blogspot.com
On It's coming soon posted 2 years, 3 months ago 15 ResponsesCarbon:Hydrogen Ratio
Right, as sunflower points out, the ratio of hydrogen to carbon makes a big difference in how heavy a carbon tax hits a given fuel. Coal is typically around 1:1. Gasoline (octane) averages 2.25:1. Methane is the best hydrocarbon, at 4:1.
-- entropyproduction.blogspot.com
On It's not the same as a carbon tax, and it's not cool posted 2 years, 4 months ago 13 ResponsesDeferred Demand
I prefer the term 'deferred demand' to 'demand reduction', because it better describes what you are doing. The fact that you have to devote a paragraph to excluding 'demand reduction' from energy efficiency illustrates said point.
May I also politely suggest that you drop the acronyms as well? Defining a new piece of terminology, and then obscuring it with an acronym makes everything a little less clear. You don't need them, they break up the pace of the piece, so why bother?
-- entropyproduction.blogspot.com
On Information is power posted 2 years, 4 months ago 24 ResponsesEnergy is not Work
People who forecast the cost of 'replacing all energy consumption with (renewable) electricity' generally do not understand the concept of entropy. Joule per joule, electricity can do more work then a unit of oil or coal. Practically, electricity can do approximately 3x the work of a fossil fuel. Consider home heating. A joule of natural gas provides a joule of heat, but a joule of electricity can provide ~3.5 joules of heat with a heat pump.
-- entropyproduction.blogspot.com
On Solar has arrived posted 2 years, 4 months ago 16 ResponsesLife Expectancy
Gmunger beat me to the point about osteoporosis, but just to note the actual numbers, life expectancy in South Africa is only 51 years versus 79.5 for Norway. So it seems extremely difficult to argue that any difference in the bone health of the two countries' populations is due to their diet since Norwegians live 56 % longer.
http://www.who.int/countries/nor/en/
http://www.who.int/countries/zaf/en/
-- entropyproduction.blogspot.com
On On the difficulties of going veggie posted 2 years, 4 months ago 65 ResponsesRe: FWIW
Actually, I accept that hydrogen is a wonderful chemical building block. That problem with that, as we see in discussion above, is that you have to un-build it, break it apart, to join it again as molecular hydrogen (H2).
It is hydrogen's success as a 'building block' that makes it hard to get as an energy carrier.
This is not what he claimed. For hydrogen to form other elements it has to undergo nuclear fusion. Ergo, nuclear fusion is not a chemical reaction, it is an interaction of strong nuclear force. His claim is roughly equivalent to saying gravity holds a water molecule together.
-- entropyproduction.blogspot.com
On A guest essay from Geoffrey Holland posted 2 years, 4 months ago 55 ResponsesBunk
Point by point rebuttal:
While this may be true for the universe in general, it is not true on this planet.
* It is the simplest, most abundant substance in the universe. About 90 percent of all atoms that exist are hydrogen atoms.
* It is the chemical building block for all the other elements, indeed all that exists.
If by 'chemical' you mean 'nuclear', I might accept that. Chemistry is generally the science of electron bonding, and since hydrogen normally doesn't include neutrons, I don't know how you can justify this statement.
* It is the fuel that powers the stars, including our own sun.
Partially true, but substantial energy contribution comes from the fusion of heavier elements, such as carbon forming iron. Irrelevant to hydrogen's suitability as an energy carrier.
* It is the fuel that powers life ... the ultimate source of energy for all living things.
Given that none of oxygen, glucose, or ATP are molecular 'hydrogen' I don not know where this claim arises.
* It is the best fuel alternative to liquid and gaseous fossil hydrocarbons like oil and natural gas.
Unsubstantiated.
* When consumed, it is entirely pollution free in most cases and nearly so in all the rest.
True, but sidesteps the obvious issue of production. All industrial hydrogen production is produced by the steam-reforming of natural gas, or rarely coal.
* It is the only energy carrier that is essentially limitless in supply.
Clearly false, photons and electrons are not in 'short supply'.
* It is the only fuel that will go down in cost to the customer over time, as demand increases.
Unsubstantiated.
* It is no more dangerous to use than gasoline or natural gas. The evidence suggests that, in some ways, it may well be safer
A flat out lie. I work with hydrogen as a process gas for vacuum evaporation of thin films and it's the most dangerous one we have. Hydrogen can detonate from static electricity in pretty much any concentration. Here's a Material Safety Data Sheet:http://www.praxair.com/praxair.nsf/0/ea179e7fb21df0858525 ...
We store our hydrogen cylinder in a special cabinet equipped with a sensor to detect leaks and a sprinkler to douse it if one occurs.
The idea that 'NASA uses it so it must be safe' is a straw man. NASA uses highly toxic hypergolic hydrazine and nitrogen tetroxide in the attitude control thrusters of the shuttle. This doesn't make them 'safe' for public use by Joe Smoe.
I have discussed the drawbacks of hydrogen before I would like to present what I wrote last year about the three inescapable problems associated with hydrogen production, storage, and generation:
http://entropyproduction.blogspot.com/2006/07/hydrogens-d ...
Warning: my post contains some numbers, unlike the above by Geoffrey Holland.
-- entropyproduction.blogspot.com
On A guest essay from Geoffrey Holland posted 2 years, 4 months ago 55 ResponsesScientific basis for iron seeding
Here is a link to a review from the journal Science regarding iron-deficiency in the ocean:
http://www.sciencemag.org/cgi/content/abstract/315/5812/6 ...
The abstract states:
Since the mid-1980s, our understanding of nutrient limitation of oceanic primary production has radically changed. Mesoscale iron addition experiments (FeAXs) have unequivocally shown that iron supply limits production in one-third of the world ocean, where surface macronutrient concentrations are perennially high. The findings of these 12 FeAXs also reveal that iron supply exerts controls on the dynamics of plankton blooms, which in turn affect the biogeochemical cycles of carbon, nitrogen, silicon, and sulfur and ultimately influence the Earth climate system. However, extrapolation of the key results of FeAXs to regional and seasonal scales in some cases is limited because of differing modes of iron supply in FeAXs and in the modern and paleo-oceans. New research directions include quantification of the coupling of oceanic iron and carbon biogeochemistry.
While I am leary of geo-engineering schemes, I wouldn't claim this is junk science. Table 1 in the article shows chlorophyll concentrations going from 0.2 to 0.6 mg/m^3 for one seeded bloom, 0.5 to 2.8 for another, etc. The data seem to suggest that seeding in the summertime is the most efficient way to promote plankton growth.
Supplementary tables available here:
http://www.sciencemag.org/cgi/content/full/315/5812/612/D ...
On In an op-ed, Russ George claims his company has been unfairly maligned posted 2 years, 5 months ago 29 ResponsesSolar need not be Everywhere
The regulatory environment of Arizona, or even the bulk of the USA, is not really relevant to the conclusions of my article.
On Regulatory infrastructure will be crucial posted 2 years, 6 months ago 12 Responses