Whether it’s for business, pleasure, or just the daily minutiae we all need to manage, transportation is a critical part of our lives; In the US, transportation accounts for almost 30% of US greenhouse gas emissions. There are lots of ways to reduce transportation’s impact, though: by designing pedestrian-friendly cities and investing in transit, by using fuel-efficient and electric cars, and by replacing oil with less-polluting and renewable fuels, including biofuels.
The most popular biofuel in the US, corn ethanol, has seen growing production nearly every year over the last several decades. In 2011, ethanol production accounted for 40% of the nation’s corn crops.
While burning a 10% ethanol/10% petroleum blend fuel can be up to 14% less than conventional fuel, tailpipe emissions are only one measure of a fuel’s environmental impact. When you look at the lifecycle costs of corn ethanol, its benefits quickly disappear. In fact, corn ethanol may be even worse for the environment than conventional gas!
Monoculture corn agriculture requires huge quantities of water, fertilizers and pesticides and competes with the land needs of edible crops, driving up food prices. Biodiversity loss and soil erosion are common results of corn ethanol and soybean diesel production and growing, transporting and processing crops is energy intensive.
But it doesn’t have to be this way. Biofuels can be made from all sorts of organic material and some are proving to be more environmentally-friendly than others.
“Second-generation” biofuels like those made from grasses (cellulosic) and algae have the advantage of being less energy intensive and do not compete with food crops. They require little or no fertilizers, and in the case of grasses, can actually improve soil health in certain cases.
Renewable Fuel Standard (RFS) regulations passed by Congress in 2005 and 2007 require a certain amount of our transportation fuels to come from renewable sources. Although corn ethanol still comprises the bulk of the RFS program, the law was designed to transition to second-generation biofuels over time.
Is the RFS harming or helping the environment? EarthShare members give the policy mixed reviews. Friends of the Earth believes that law’s support of corn ethanol is a fatal flaw. If it can’t be fixed, they say, the RFS should be scrapped:
“The federal government should not mandate the commercial production of biofuels, conventional or advanced, before we fully understand the risks they pose to our natural resources and global communities.”
The Union of Concerned Scientists thinks the law has the potential to work only if the country steps up its investment in cellulosic biofuels. Their “Billion Gallon Challenge” proposes steps that could get us there:
“The United States has the potential to dramatically expand the production of these better biofuels and take a significant step toward cutting US oil consumption in half over the next 20 years. But to get there we need smart government policy, funding, and support to develop the required technology.”
The best way to reduce our transportation emissions is to simply drive less. But where that choice is impractical, biofuels will surely play a role in our transportation system. The promise of biofuels will only be achieved if we use the right ones wisely. The US has a long way to go to meet that promise.
Cleaner Biofuels: Displacing Conventional Gasoline, Union of Concerned Scientists
Smart Choices for Biofuels, Sierra Club
Biofuels, Friends of the Earth
NRDC Policy Basics – Biofuels, Natural Resources Defense Council