So the questions I've been getting today are do yesterday's Science articles mean that all biofuels are bad and that the recently passed RFS is going to harm the climate? The short answer is no and no. It remains relatively easy to construct theoretical scenarios where biofuels contribute significantly to our transportation energy needs in a low-carbon way, avoiding the direct and indirect land-use traps addressed in the articles. The challenge remains how do we drive the biofuels industry to produce these types of biofuels.
Unfortunately, most stories today on the articles are righting off all biofuels and giving short shrift to the policy questions. (See this Wired story and this NY Times article.)On the other extreme, Bob Dineen from the Renewable Fuels Association calls these studies "simplistic," and in a comment on my post from yesterday, Tim Raphael from Pacific Ethanol tried to discredit the whole idea of indirect impacts.
The dynamics the authors have identified are undeniable--if you clear land to grow crop for biofuels you have to account for the emissions from that clearing and if you induce clearing by driving up crop and land prices, you also have to take responsibility for those emissions. For laying out these dynamics and giving us a sense of the scale, we all owe them a debt of gratitude, particularly Searchinger and his team because the emissions from indirect land are hard for many to understand. The analysis of the indirect land-use impacts uses one of the most respected agricultural economic models, but it is only that--one model. Others have been doing similar analysis using at least partly a different model and getting different results. And many folks will make the case for different assumptions and inputs into the models.
Fortunately, we knew about these dynamic before yesterday, and we’ve won a preemptive victory in getting the dynamics written into the legislation in the form of the land-use safeguards and minimum lifecycle GHG standards (which as I noted a few weeks ago include, by law, the indirect land-use emissions). Now we have to defend these provisions and make sure a scientific debate (not one issue of Science) guides the implementation.
So I would caution folks from assuming that either article means that no crop-based biofuels will be able to comply with the RFS or that their analyses are definitive. Of course, it is definitely possible (and taking Searchinger's numbers at face value very likely) that the amount of truly low-carbon biofuels we can drive through real politics and real markets is much smaller than we would hope. This makes the urgency around getting a federal low-carbon fuel standard all the greater. (See Roland's post on this too.) This approach broadens the competition among low-carbon energy supplies for transportation and focuses purely on the benefits we need rather than number of gallons produced.
The challenges of getting biofuels right also means that we need to step up our efforts on renewable electricity, transmission, and electrification of transportation. Similarly, demand reductions are almost always the cheapest, cleanest, and fastest way to reduce GHG emissions. We need to be looking for ways to dramatically increase VMT reductions and further increase vehicle efficiency (beyond our recent victory increasing CAFE standards).
But recall that we’re struggling with how to get biofuels on the right path not out of some perverse desire to work on difficult tasks, but because the other parts of the transportation solution set also face major challenges in scaling up and doing it quickly. The pie-charts above are based on very aggressive scenarios for plug-in hybrids and smart growth/VMT reductions and different levels of efficiency. There are no easy solutions to a low-carbon transportation sector that do not require a significant contribution from biofuels. The challenges facing vehicle efficiency, electrification, VMT reductions, smart growth are different from those facing biofuels (they lessen the benefits we can get instead of risking costs), but for me, they do mean that the just-say-no approach to biofuels is irresponsible.