I normally work in astrophysics, but one of my other interests is energy, energy security, reduction of fossil fuel use, and environment. I put this page together for both you and me to collect a few references and lead to more. It can be helpful to know what's really going on, even if it is a bit messier than we would like.
Please DO NOT quote me as an employee of Lawrence Berkeley National Lab - I AM NOT. The material and opinions expressed here are absolutely not those expressed, paid for, condoned, or even tolerated by LBNL or the University of California.
This panasonic web page says that NiMH Prius batteries retain 80% of their capacity after something like 9000 charges or "cycles".Ê
http://www.peve.jp/e/hevjyusi.html
I was not able to find information so easily for comparison on Li-ion or Li-Polymer. ÊI did, however, find a chart in the Wikipedia that says either lithium is about 3-4 X more energy intensive by weight than NiMH, but lasts about 1000 cycles. Ê
http://en.wikipedia.org/wiki/Rechargable_batteries
This is the basis of my damning assesment of plug-in Hybrids -
THE REALLY NASTY THING THEY DON'T TELL YOU ABOUT PLUG-IN HYBRIDS: Lithium batteries are inevitabley the choice for these (they store 3-4 more times more energy per weight, according to most figures I have seen (wikipedia and Panasonic web pages) and figure heavily in the Volt. Unfortunately, the LIFETIME OF LITHIUM BATTERIES IS EXTREMELEY SHORT. (Thanks to Rich Muller for pointing this out to me.) According to Panasonic, the maker of the Prius Battery, Prius NiMH battery Capacity doesn't fall by 20% until more than 9000 cycles. Both Lithim-Ion and the more advanced Lithium-Polymer batteries have a lifetime of more like 1000 cycles - oops - if you use your car every day 3 year life is too optimistic (I don't know how partial charges stack up to "cycles" but in the simplest case if you drive once and charge every day, you have to replace your full battery pack every three years), perhaps 8 times as often as with NiMH. Forget it! OK,well maybe some day batteries will be fantastic - there is still this minor niggling problem of where to get plentiful cheap and clean energy. And that's enough right there. No difference between this and a hydrogen car.
The ERG (energy resources group) at UC Berkeley did a good job of reviewing and fairly comparing different claims on net energy from corn ethanol and separately, greenhouse gas emissions. The results show that this business is always complicated. This group claims that "co-prodcuts" of corn ethanol are not fairly counted: For example, if you make corn oil as a result of your ethanol process, this will surely be sold, eliminating the need for energy to be expended elsewhere. This changes the sign of the net energy for the process - an enormous difference (*). The results of the study on greenhouse gases, however, are damning:
"The published results, adjusted for commensurate system boundaries, indicate that with current production methods corn ethanol displaces petroleum use substantially; [however] only 5 to 26% of the energy content is renewable. The rest is primarily natural gas and coal (Fig. 2). The impact of a switch from gasoline to ethanol has an ambiguous effect on GHG emissions, with the reported values ranging from a 20% increase to a decrease of 32%."
The really important point here is that LOTS of Coal, the dirtiest popular form of energy (though much of it domestically produced) goes into making corn ethanol. Put another way, If you switched over to 100% ethanol tomorrow, we would still use 95% to 74% as much fossil fuel (because both oil and coal are greenhouse gas producing fossil fuels)!
Note that the authors also study a "carbon intensive" scenario (not their "best point" scenario) that shows that in certain projects proposed by the ethanol lobby, much more greenhouse gasses would be emitted, and the net gain in energy would be about a factor of 4 smaller (around 1.2 MJ/l vs. around 4.7 MJ/l, that is 1e6 Joules of useful fuel energy out compared to how many Joules of fuel energy go into the process, again giving credit for co-products) .
(*)[I wonder if this takes into account a saturation of the market at the required scale- if we scale up to make billions of gallons of ethanol to supply cars, and billions of gallons of free corn oil come with it, would we really use it all?]
Farrell 206 Article Farrell et al. 2006, Science, 311,506
• Some of the original references stating that corn ethanol are energy negative come from Pimintel, Patzek, and Ho, S. These are plant scientists. (Pimintel has been identified with a website which has politically controversial ideas about immigration, which has been used on the net to smear these results.)
D. Pimentel, T. D. Patzek, Nat. Resources Res.14, 65 (2005)
Ho, S.P. “Global Warming Impact of Ethanol Versus Gasoline.” Presented at 1989 National Conference, “Clean Air Issues and America’s Motor Fuel Business.” Washington DC, October 1989.
T. Patzek, Crit. Rev. Plant Sci. 23, 519 (2004).
• Shapouri has a research group at the USDA which publishes the very rosy picture for corn ethanol and is critical of the Pimintel-Patzek studies
H. Shapouri, A. McAloon, ‘‘The 2001 net energy balance of corn ethanol’’ (U.S. Department of Agriculture, Washington, DC, 2004). Also available at www.usda. gov/oce/oepnu.
NYTimes reported a study which showed that all biofuels - the ideal miscanthus cellulosic ethanol, not just corn ethanol - cause release of carbon currently sequestered in non-agricultural land, and that this release DWARFS the carbon emission saved by even the best cellulosic biofuel process. In other words, we could run our country as green as we want, but somewhere else in the world they will practice slash-and-burn agriculture to offset the land going out of agricultural production. The really essential point is not that they will burn the rainforests - the essential point is that the carbon content of the meanest scrubland as scrubland instead of ag land is huge - and not so different from rainforests.
Searchinger., T et al. Science 29 February 2008 319: 1238-1240 - economic analysis
Joseph Fargione, Jason Hill, David Tilman, Stephen Polasky, and Peter Hawthorne
Science 29 February 2008 319: 1235-1238 - calculation of carbon released when land converted to biofuel production.
I am by no means certain that this study is the most important source, but it is an important source for the idea that policitians frequently use new energy technology as a misdirection to avoid sober evaluation of energy policies in the near term. This is a 2003 NRDC (National Resources Defense Council) report. In this report they identify the Bush Administration "hydrogen economy" vision as so hopelessly far in the future, and with such small potential for even medium and long-term impact, that it could only be considered misdirection. The really powerful part of the report is that they do a good job pointing out the huge potential for saving on fossil fuels (and therefore reducing pollution, greenhouse gasses, money to middle eastern dictatorships, etc. ...) by the simplest conservation measures. It seems to me that these ideas, if not directly, were picked up in the next year or two in influential New Yorker Magazine and New York Times articles.
"Dangerous Addiction 2003: Breaking the Chain of Oil Dependence" is a report by the NRDC by Daniel Lashoff and Roland Hwang.
2010 Nov. 30: Senators Feinstein, Kyl Lead Bipartisan Letter Calling for Ethanol Tariffs and Subsidies to Expire
Incredibly, numerous republicans AND democrats TOGETHER are taking aim and this damaging, overpriced Ethanol Boondoggle. It is particularly interesting that the very next week, there was outrage over all sorts of pork in the "Obama-Republican Lame Duck Tax Bill", the very next week (2010 Dec. 5-10), and earmarks were complained about, though ethanol barely mentioned.
http://feinstein.senate.gov/public/index.cfm?FuseAction=NewsRoom.PressReleases&ContentRecord_id=9dc7dae1-5056-8059-76e3-f312b0ac5587&Region_id=&Issue_id
Here is full text:
November 30, 2010
The Honorable Harry Reid The Honorable Mitch McConnell
522 Hart Senate Office Building 361A Russell Senate Office Building
Washington DC, 20510 Washington DC, 20510Dear Majority Leader Reid and Minority Leader McConnell:
We are writing to make you aware that we do not support an extension of either the 54 cent-per-gallon tariff on ethanol imports or the 45 cent-per-gallon subsidy for blending ethanol into gasoline. These provisions are fiscally irresponsible and environmentally unwise, and their extension would make our country more dependent on foreign oil.
Subsidizing blending ethanol into gasoline is fiscally indefensible. If the current subsidy is extended for five years, the Federal Treasury would pay oil companies at least $31 billion to use 69 billion gallons of corn ethanol that the Federal Renewable Fuels Standard already requires them to use. We cannot afford to pay industry for following the law.
The tariff on ethanol makes our country more dependent on foreign oil. The tariff is nine cents per gallon higher than the ethanol subsidy it supposedly offsets, and this lack of parity puts imported ethanol at a competitive disadvantage against imported oil. This discourages transportation fuel imports from Brazil, India, Australia, and other sugar producing countries, and leads to more oil and gasoline imports from OPEC countries that enter the United States tariff-free. Eliminating or reducing the ethanol tariff would diversify our fuel supply, replace oil imports from OPEC countries with ethanol from our allies, and expand our trade relationships with democratic states.
The data overwhelmingly demonstrate that the costs of the current ethanol subsidy and tariff far outweigh the benefits. According to a July 2010 study by the Congressional Budget Office, ethanol tax credits cost taxpayers $1.78 for each gallon of gasoline consumption reduced, and $750 for each metric ton of carbon dioxide equivalent emissions reduced. The Center for Agricultural and Rural Development at Iowa State University recently estimated that a one-year extension of the ethanol subsidy and tariff would lead to only 427 additional direct domestic jobs at a cost of almost $6 billion, or roughly $14 million of taxpayer money per job.
Historically our government has helped a product compete in one of three ways: subsidize it, protect it from competition, or require its use. We understand that ethanol may be the only product receiving all three forms of support from the U.S. government at this time.
Eliminating or reducing ethanol subsidies and trade barriers are important steps we can take to reduce the budget deficit, improve the environment, and lessen our reliance on imported oil. We look forward to working with you on responsible energy tax policy.
Sincerely,
Dianne Feinstein, United States Senator
Jon Kyl, United States Senator, United States Senator
Jack Reed, United States Senator
Richard Burr, United States Senator
Benjamin Cardin, United States Senator
Mike Enzi, United States Senator
Jim Webb, United States Senator
Bob Bennett, United States Senator
Barbara Boxer, United States Senator
John McCain, United States Senator
Sheldon Whitehouse, United States Senator
Tom Coburn, United States Senator
Susan Collins, United States Senator
Bob Corker, United States Senator
Jeanne Shaheen, United States Senator
Mark Warner, United States Senator
Chris Coons, United States Senator###
Please feel free to contact me with personal correspondence (not spam or invective, thanks) at:
Bruce[underscore]Grossan[at sign]lbl[dot]gov (anti-spam
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Last Update 2010 Dec 11