They all crush ‘clean coal’: Stanford study, part 1 8

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1. 

   Ken Johnson Posted 3:34 am
   16 Dec 2008

   What are the red and blue bars?

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2. 

   KenG Posted 4:17 am
   16 Dec 2008

   What Does It Mean?The inclusion of the delay in carbon impact is cute, but does it have any real meaning? Only if you think there is a single solution to the CO2 issue. No single technology can substitute for existing carbon emitters. No single technology or combination of technologies can replace coal/gas/oil in the upcoming 5, 10 or 20 years. As a result, penalizing technologies that take longer to implement is a very artificial way to bias the evaluation.
   Also, the lifetime assumptions are suspect. Current US nuclear plants are almost all going to operate for 60 years and the next generation are expected to operate for 80 years, rather than the 40 years assumed. Wind lifetime is hard to evaluate. The turbines will probably be limited to 20 years or less but the foundations (a significant part of the CO2 footprint) may be able to be reused and last 100 years.
   I haven't had time to fully read the paper, but I think the uncertainty on the evaluation is very large.

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3. 

   Patrick McCully Posted 9:54 am
   16 Dec 2008

   Jacobson massively underestimates hydro emissionsJacobson has neglected to include the emissions (mainly methane) from hydropower reservoirs due to the decomposition of biomass. In the tropics these emissions can be very significant - hydro in the Brazilian Amazon averages well over 2000 gC02e/kWh. Measured emissions from Canadian reservoirs average 36 gC02e/kWh. A recent study from a small reservoir in Switzerland found methane emissions of 119 gC02e/kWh. The "life-cycle" numbers for hydro quoted by Jacobson of 17-22 gC02e/kWh cover only construction emissions. For more info see http://www.internationalrivers.org/en/node/383.
   Patrick - internationalrivers.org/blog

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4. 

   Bob Wallace Posted 11:53 am
   16 Dec 2008

   asdf"No single technology or combination of technologies can replace coal/gas/oil in the upcoming 5, 10 or 20 years."
   That's apparently not the case.
   The 2007 Stanford study that looked at output data for geographically divergent wind farms found that we can rely on about 35% of produced power as reliable base load.
   We don't really need to over build wind by a factor of three. Solar PV and thermal solar can take up a lot of the daytime/peak needs.  Other forms of generation such as geothermal can give nice steady feeds to smooth things out.
   It's not really a question of "can", but a question of "whether".  Whether we decide that it's a job that we need to get done.
   
   

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5. 

   Karen Street Posted 1:16 pm
   16 Dec 2008

   peer reviewFirst of all, peer review means that the ideas have been submitted to the policy community for their consideration. It will be interesting if Jacobson is right, and we have so many solutions that we can throw some away, since this is not what the analysis of others show. We'll see if these ideas are accepted over time.
   An unusual analysis: from Jacobson's text, the blue bars are the GHG emissions/kWh, based on assumptions different from what I've seen elsewhere, and the red bars are a category called opportunity cost emissions due to delays. We'll see if this methodology is adopted by the next IPCC WG3.
   If we can meet European times for nuclear power, then we can build a plant including approval in 4 years. It might not be that fast here, but that's a pretty good time.
   A Musing Environment
   
   Karen Street

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6. 

   BILL HANNAHAN Posted 5:13 pm
   16 Dec 2008

   The most important sentence is.
   
   Costs are not examined since policy decisions should be based on the ability of a technology to address a problem rather than costs
   
   
   Without cost data, practicality is impossible to determine.
   Denmark generates about 19% of its electric power from wind energy.
   
    
   The author omits several important points about Denmark.
   1      Denmark has been pushing wind with huge subsidies for 30 years.
   2     Denmark has the most expensive electricity in the world, about 40 cents/kWh.
   3     Denmark exports half its wind power due to intermittency problems, so only 9.5% of electricity consumed in Denmark is wind. It imports hydro and nuclear power.
   4     Denmark uses half the power per person as the U.S., so if we matched Denmark's performance, wind would be about 5% of  U.S. total.
   it is a valid exercise to estimate the potential number of immediate deaths and carbon emissions due to the burning of buildings and infrastructure associated with the proliferation of nuclear energy facilities and the resulting proliferation of nuclear weapons.
   The author overlooks several points here.
   1     The Manhattan project began in 1942 when knowledge of nuclear weapons design was nil yet the U.S. had working examples of two designs in 1945. The physics and chemistry of nuclear weapons is well known now.
   2     A simple unpressurized plutonium production reactor can be built with a small fraction of the money and time of a nuclear power plant.
   3     To make plutonium 239, uranium is exposed to neutrons in a reactor for only a few weeks. Commercial spent fuel has been in the reactor 3-5 years and contains higher isotopes of plutonium that are highly radioactive and heat producing, making bomb design and construction very difficult.
   4.     Uranium supplies are abundant. Reprocessing is not required with Gen III reactors.
   5     Enrichment facilities should be limited to large stable countries, and made available to all countries at a reasonable price, if they cooperate with the IAEA. It is a small fraction of the cost per kWh.
   6     No nation builds bombs from spent commercial reactor fuel. Giving up the most difficult and unused paths to nuclear weapons leaves the easy paths still at hand.
   Currently, about 30 000 nuclear warheads exist worldwide, with 95% in the US and Russia, but enough refined and unrefined material to produce another 100 000 weapons.
   
    
   There are only two ways to make this material unavailable. Explode the bombs or burn it up in commercial power reactors.
   For nuclear energy, we add, in the high case, the potential death rate due to a nuclear exchange, as described in Section 4d, which could kill up to 16.7 million people. Dividing this number by 30 yr and the ratio of the US to world population today (302 million : 6.602 billion) gives an upper limit to deaths scaled to US population of 25 500 yr−1 attributable to nuclear energy.
   
    
   Romm tries to brush this off because the carbon emissions are small, but the real reason the  author includes it is to get an annual death toll similar to that from  the routine operation of coal plants.
   In the case of centralized power sources, the larger the plant, the greater the risk of terrorism and collateral damage.  
   A grid relying on intermittent sources requires massive long range transmission capacity which would be a terrorist's delight. Scientific American published A Solar Grand Plan
   http://www.sciam.com/article.cfm?id=a-solar-grand-plan
   calling for a transmission system that could be used to kill millions of Americans.
   http://gristmill.grist.org/story/2008/8/24/165645/794#com ...
   nuclear power plants are vulnerable to heat waves. Because nuclear power plants rely on the temperature differential between steam and river or lake water used in the condenser, they often cannot generate electricity when the water becomes too hot, as occurred during the European heat wave of 2004, when several nuclear reactors in France were shut down....
   nuclear power plants have unscheduled outages during heat waves
   
    
   The author makes it sound as if nuclear plants fail under heat wave conditions. In reality the plants were shutdown due to regulatory limits on river temperature. Those limits could have been waved.
   Nuclear and fossil plants on rivers and lakes often have cooling towers to avoid this problem, as a satellite photo trip down the Ohio River will show.
   Solar thermal plants and geothermal plants operate on lower temperature steam making them less efficient than nuclear plants, especially with high condenser temperature.
   Solar cell efficiency drops off at high temperatures.
   Hot air is less dense and therefore delivers less power to windmills than cold air at the same speed. Windmill maintenance is often scheduled for the summer because that is their worst season. Nuclear plants have above average capacity factors in the summer because maintenance is scheduled for spring and fall when demand is lowest.
   The author only mentions the temperature effects on nuclear, and he misrepresents those.
   interconnecting 19 wind farms through the transmission grid allowed the long-distance portion of capacity to be reduced, for example, by 20% with only a 1.6% loss in energy. With one wind farm, on the other hand, a 20% reduction in long-distance transmission caused a 9.8% loss in electric power.
   Cost was not included in the study, except when it favored wind by comparing one wind farm with many wind farms. The author does not mention that transmission costs are far less per kWh for nuclear because the average distance traveled for each kWh is much less and the average capacity factor of the power lines is much higher.
   all cases considered involve combinations of the technology with either BEVs, HFCVs, or E85.
   Wind power needs storage so the author conveniently adds battery electric vehicles to the mix as if is free storage.
   Imagine that you bought a Chevy Volt three years ago and you find that the range is falling off lately. You dropped it off at the dealer this morning and the manager is calling.
   "We see from our diagnostic system that your battery has had several hundred high rate charge/discharge cycles while sitting in your garage. That is not covered under the warranty. We can install a new battery for $11,500, prepaid."
   People will require substantial payments in exchange for use of their cars battery.
   Round trip charge/discharge loses are typically 20-30%. During calm periods you may find that your battery is being drained to charge your neighbors car, resulting in a compound loss. Who will pay for this expensive battery capacity and energy losses?
   The author makes carbon calculations based on the existing fuel mix. To really compare alternatives he should assume the grid is powered by the source in question. That would reduce nuclear CO2/kWh to near zero.
   The author is comparing 1945-1965 nuclear technology with experimental 2020 technology. Cold war diffusion enrichment plants use vastly more energy than modern centrifuge technology, which in turn may be eclipsed by laser enrichment.
   Rebuilding a facility like Offshore Power Systems to mass produce nuclear power plants the way Boeing builds airliners would dramatically change the comparison.
   http://www.atomicinsights.com/aug96/Offshore.html
   
   Things Everybody Should Know About Energy

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7. 

   vakibs Posted 7:45 pm
   16 Dec 2008

   the wind emperor's new clothes We have two technologies for which the fuel is essentially free and produces no CO2.
   Can somebody explain why the first technology (wind) which takes 50 times more land, 10 times more concrete and 50 times more steel has lower construction times or lower CO2 emissions than the second technology (nuclear) ?
   
   Let's think in terms of eco-dollars.

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8. 

   Max8806 Posted 10:23 pm
   16 Dec 2008

   Opportunity CostsGood points Bill, I'd just add one more. I'm still trying to wrap my head how you would possibly justify calculating the opportunity cost of time/delays, but ignore the opportunity cost of cost. Once you acknowledge we have limited resources and need to consider opportunity costs, how you could possibly ignore $/delivered KWh is beyond me...
   
   
   
   Max Epstein

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