Tuesday, October 1, 2013

Alternative fuels: maybe not so fast

Someone long ago pointed out that we'd run out of atmosphere -- meaning its ability to safely soak up excess CO2 -- well before we ran out of coal. Now that global warming has progressed from a seemingly remote risk to a clear and present danger, it's heartening that U.S. leaders are finally starting to tackle greenhouse gas (GHG) emissions from power plants where coal use is concentrated. Addressing such energy sector emissions is a centerpiece of the new climate plan announced by President Obama in July.

As it turns out, such action to address GHG emissions upstream, meaning in the energy and resource systems that supply the fuels used downstream in our everyday lives, is also the next important step needed to control CO2 emissions from cars and other forms of transportation.

What's the connection, you might say? Aren't we already doing a lot to put clean fuels on the road through tax credits and other subsidies for various alternative fuels and vehicles (AFVs), the Renewable Fuel Standard (RFS), the president's 2011 pledge to put a million electric vehicles (EVs) on the road by 2015 and numerous other Clean Cities programs? These are just a part of broader nationwide alternative fuel efforts, which also include California's Zero-Emission Vehicle (ZEV) mandate, Hydrogen Highway and other state programs, as well as earlier programs such as President G.W Bush's FreedomCar and cellulosic ethanol initiatives (the latter inspiring key provisions of the RFS).

Public policy promotion of alternative fuels is a legacy of the 1970's oil crisis, when concerns about oil depletion and import dependence ushered in a new generation of energy strategy. Such fears were reawakened by the 9/11/2001 attack and further reinforced as oil prices rose over the next decade. "Peak oil" theory got lots of airplay.

Unlike the situation for coal, it was assumed that running out of oil would spur the market for alternatives, so that the goals of cutting carbon and getting off of oil were well aligned. The transportation portions of climate policy would then advance under the banner of energy independence, a politically popular pledge made by every president since Richard Nixon. President Obama's climate plan reaffirms the commitment to AFVs, highlighting the RFS and ongoing federal efforts "to deploy cleaner fuels, including advanced batteries and fuel cell technologies, in every transportation mode."

One might wonder what's not to like about this strategy. After all, electric cars are "zero-emission vehicles" and biofuels are basically "carbon neutral," right? 

In reality, applying the word "clean" to any motor fuel is rhetorical slight-of-hand. Regardless of their origin, liquid fuels like gasoline or ethanol and diesel or biodiesel vary only trivially in terms of CO2 emitted from the tailpipe. Electricity and hydrogen both avoid emitting CO2 from vehicles directly; for those fuels, the action is obviously upstream. But whether what propels a car is electricity, liquid or gas, the critical impacts all occur far from the car itself at locations where fuels originate. Today, none of the relevant sectors -- electric power generation, oil and gas supply, agriculture and land -- are close to being seriously carbon constrained.

The implication is that until much greater emissions reductions are achieved in the sectors that supply fuels, there's no good reason to rush AFVs onto the road. That's the point elaborated on in my article entitled "Why pushing alternative fuels makes for bad public policy" on Yale's e360 e-zine. 

This skepticism is based in turn on a rigorous analysis, "Factoring the car-climate challenge," that works forward from present realities rather than backward from one imaginary future or another. The upshot is that, although one or more alternative fuels might have a constructive climate protection role to play someday, which particular alternatives will be needed and when cannot be determined on the basis of current data. It's also quite possible that none will be relevant in the forms that AFVs are being promoted today.

The e360 piece provoked a good bit of commenting, which you can read following the article itself. In one of the comments, I give a general response to several of the initial comments. In other posts on this site, you can find more specific responses to comments about particular topics, particularly the issues that surround CO2 and biofuels. 

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