Deron Lovaas's Blog
Setting the Record Straight, Again
January 17, 2008
Posted by Deron Lovaas in Living Sustainably , Moving Beyond Oil
"A groundless rumor often covers a lot of ground."
- Anonymous
An old claim has been brought to my attention again. Hybrids pollute more than Hummers because of one component: The battery. Not believable, and definitely not true!
The best tool for debunking rumors like this is Argonne National Lab’s GREET (Greenhouse gases, Regulated Emissions, and Energy use in Transportation) Model. The respected Society of Automotive Engineers dubbed it the “gold standard” model for analyzing vehicles and fuels.
Argonne juxtaposed comparable internal combustion and hybrid cars, and did indeed find that the latter will yield slightly more global warming pollution in the manufacturing process. BUT – production accounts for a mere 10-20% of a vehicle’s lifetime emissions profile. Far more important is 15 years of driving, the average for cars. Take that into account, and you find that a regular car's lifetime emissions are nearly TWICE those of a hybrid.
The “regular car” in this example gets 25 mpg. Since the Hummer is lucky to hit double-digits in mpg its lifetime heat-trapping pollution eclipses the hybrid's.
Thanks to my colleague Luke Tonachel for passing along this analysis, and for adding some points to keep in mind when considering environmental downsides of batteries:
- All cars use batteries and the elements for those batteries, whether lead in conventional vehicles or nickel in today’s hybrids, are mined. Mining is not without environmental problems.
- Lead is more pervasive and therefore more toxic than nickel.
- Nickel batteries, like lead batteries, can be recycled.
- The use of nickel metal hydride batteries enables the hybrid car to exist because lead batteries would be too big and heavy to provide the same performance in a hybrid that they have today.
- Nickel batteries will soon by transitioning to lithium batteries. Lithium batteries can be even more environmentally benign. Lithium is not toxic and lithium batteries can pack more power into each pound of cell than nickel metal hybrid batteries, enabling cars to use more clean electrical energy and less gasoline without weighing down the vehicle further. Some cars in Japan already have lithium batteries and they will likely be in US vehicles in the next couple of years.
(bookmark or email this entry)
Comments are closed for this post.
- Deron Lovaas
- Vehicles Campaign Director
- Washington, D.C.
- I joined NRDC after working for several other conservation groups and Maryland's Environment Department. I...
- more→
Comments
Joseph Romm (ClimateProgress) — Jan 21 2008 11:36 AM
Prius easily beats Hummer in life-cycle energy use.
Deron: I thought you'd like to see this debunking I did of the absurd original "analysis."
http://climateprogress.org/2007/08/27/prius-easily-beats-hummer-in-life-cycle-energy-use-dust-to-dust-report-has-no-basis-in-fact/
As I noted at the time, this report "is the most contrived and mistake-filled study I have ever seen — by far (and that’s saying a lot since I worked for the federal government for five years). I am not certain there is an accurate calculation in the entire report. I say this without fear of contradiction because this is also the most opaque study I have ever seen — by far. I defy anyone to figure out what their methodology was."
Ian @ NRDC — Jan 21 2008 12:52 PM
Joe -- thanks for the pointer to your original critique. It'd never occurred to me that reviewing bad "science" could be every bit the art form that film critics have made out of panning the celluloid rotten tomato. :-)