Yesterday, Sen. Bingaman, chair of the Energy and Natural Resources Committee, said that he thought the energy bill debate would continue on into December. On the one hand, this suggests that momentum for a comprehensive bill is flagging; on the other hand, a little more time might allow for a broad coalition of ag, ethanol, and enviro to come together behind a good RFS. As I've written about before, a good RFS package is probably the linchpin to the energy bill. (For a great overview of the energy bill, see this post over at Grist by my colleague, Julia Bovey.)
Here are the talking points that we're using these days to try to convince legislators to do a renewable fuel standard in an environmental responsible way and below them a few notes on our calculations:
- Done right, with proper environmental safeguards, the RFS can contribute over 2 billion metric tonnes of avoided CO2 pollution to the fight against global warming and reduce our dependence on imported oil. However, done wrong, biofuels can have grave impacts to our lands, forests, air, water, habitat, and climate.
- Unfortunately, the Senate Renewable Fuel Standard (RFS) gets it very wrong.
- The Senate RFS lacks essential safeguards to keep its five-fold increase in biofuels production from simply trading one set of environmental harms for another.
- As drafted, it incentivizes the loss of critical wildlife habitat, natural forests and grasslands, the large scale degradation of water quality, and negative impacts on human health. Its greenhouse gas reductions have gaping loopholes, and its environmental study provision lacks meaningful mitigation authority.
- From a global warming perspective alone, if we fail to include a minimum 50% GHG reduction standard for fuels beyond corn ethanol and properly account for land-use impacts from all fuels, the RFS can quickly move from providing real benefits to having none at all--or worse, contributing to emissions. For example without these two key provisions the benefits of the RFS could drop to under 1 billion metric tonnes and, if just 10% of the fuels came from lands with associated forest impacts, the RFS could have no climate benefit at all through 2030--and would contribute to the already rapid global loss of critical habitat.
To evaluate the global warming pollution, I started with the current Senate RFS, which requires the equivalent of 15 billion gallons of ethanol from corn and 22 billion gallons of "advanced biofuels," and considered it with and without a Lifecycle GHG definition that includes land-use change and a minimum standard for advanced biofuels of a 50% reduction in lifecycle GHG emissions compared to gasoline. Recall that the Senate language already requires all biofuels to provide at least a 20% reduction.
I looked at a worst case based on the Senate’s 20% minimum GHG reduction and assumed that the industry would average just 20% reductions excluding land-use through 2022. Putting aside the issue of land-use related emissions, this would actually require the industry to move backwards from current technology, so I consider this a real worst case. I also looked at a best case scenario assuming a minimum 50% requirement for advanced biofuels and assumed that corn ethanol would average a 33% reduction and advanced biofuels would average an 82% reduction. I saw some unpublished data on potential gains from corn ethanol between now and 2030 which suggested that the industry might actually be able to do better, so this might not actually be absolute best case scenario, but my number is roughly consistent with the CARD article I mentioned in my last post by Bruce Babcock.
Under these scenarios, absent land-use GHG emissions the RFS would produce cumulative reductions of between 0.9 and 2.3 billion metric tonnes CO2 equiv between 2008 and 2030. (I chose 2030 because that's the period of time we've been using to evaluate other provisions in the energy bill.)
Estimating the potential GHG emissions from land-use changes and thus the importance of getting an improved definition of lifecycle emissions is difficult. As noted in the Babcock's CARD article, direct land-use emissions--those come from the land actually used to grow the corn or other biomass used to produce biofuels--can be a reduction (e.g. growing corn on land that was used to grow soybeans) or an increase (e.g. growing corn on CRP land). The emissions can also come from land-use changes induced indirectly by the shift of acres to biofuels and the price signals that sends to farmers around the world (e.g. corn in the US displaces soybeans, soybean in Brazil displace cattle in Brazil and the cattle move into the cleared rainforest). These indirect land-use changes are also not likely to be acre for acre. Yields are different across the country and around the world and price elasticities and elasticities of substitution all make it very hard to know how much new land will be needed to meet the demands on agriculture as a whole when one acre of corn, say, is shifted from the food and feed market to the fuel market. Finally, when the land-use emissions result from virgin land being brought into production the emissions represent a one-time pulse that comes in the first few years after clearing.
To ballpark the impacts of the combined direct and indirect emissions from land-use change, I used the low-end of emissions from converting tropical rainforest to crop land published in a recent Science article (subscription required; 223 metric tonnes CO2 equiv per acre released over 30 years; here's a Wired blog post on the article for those without subscriptions). I also assumed that corn ethanol produces about 420 gallons per acre and that advanced biofuels will produce an average of 858 gallons per acre in 2008-2022. If we compare the 30 year emissions cost from land-use to the 2008-2030 benefits from renewable fuels, it would require between 10% and 27% of all gallons to have associated land-use emissions to result in zero net benefit. Obviously, if any greater percentage came from deforested land, the RFS would begin to have climate negatives. (This, of course, is only from a climate perspective. The more deforestation and other native ecosystem loss that occurs, the greater the additional collateral damage.)