Biofuels made from biomass, such as corn and soybeans, have been getting criticism lately for their impact on world food prices. Opponents of the alternative fuels say that using a portion of the world’s farmland and the associated crop yields for the production of fuel will add to the pressure developing countries face in supplying their populations with adequate food supplies. To address these concerns, countries have started creating biofuels from crops that are either inedible or of low demand, such as sugarcane and rapeseed, or on land that is unarable for traditional food crops. While these may provide answers to questions about the impact on food supplies, there are many other questions to address.
Many scientists are beginning to question whether biofuels will actually be able to help slow global warming, due to the indirect impact on land use worldwide required for the production of biofuels. The Wall Street Journal provided an example to illustrate this situation. If farmers in Brazil slash and burn more rainforest to grow food because land in the US is being used to grow grain for fuel, carbon dioxide emissions may actually increase overall. Corn-based ethanol has already been shown to increase greenhouse-gas emissions by 93% over using gasoline. Even biofuel made from switch grass grown on land that would otherwise have been used for growing corn would increase emissions by 50%. As a result, the Environmental Protection Agency is taking steps to measure each biofuel’s actual lifetime emissions to help determine which may have a positive impact on the environment, and weed out those that may be detrimental.
The emissions in question extend beyond carbon dioxide, however. A new study in Chemistry & Industry suggests that increasing the use of biodiesel worldwide may actually increase the amount of greenhouse gas emissions produced. The study compared petroleum-based diesel to biodiesel made from rapeseed over the entire lifecycle of each fuel, from production to consumption. Surprisingly, both fuels emit about the same amount of carbon dioxide, the main greenhouse gas biofuels are meant to address. However, the release of nitrous oxide, a greenhouse gas 200 times more potent than carbon dioxide, is not released equally. Petroleum fuels release 85% of their greenhouse gases when burned in the engine, while over 60% of the emissions from biodiesel occur during farming of the crop. This is because agricultural fields release a large amount of nitrous oxide, something that is not a problem with petroleum. The study concluded that by running cars on traditional diesel and planting trees on the land that was intended to be used to grow the biodiesel crop, overall greenhouse gas emissions could be reduced by one-third.
A joint study between the University of California – Berkeley and Cornell University was done to determine whether distilling ethanol from corn, switch grass or wood biomass, and making biodiesel from soybean or sunflower plants can produce more energy output in the fuel than is consumed during production. The results follow:
- Corn requires 29% more energy than is produced
- Switch grass requires 45% more energy than is produced
- Wood biomass requires 57% more energy than is produced
- Soybeans require 27% more energy than is produced
- Sunflower seeds require 118% more energy than is produced
The results are astonishing. Without government subsidies one can imagine that no company would attempt production of biofuel because the economics just don’t make sense. And considering biofuels may actually contribute to global warming, the future of biomass looks bleak for me at the moment.
However, this isn’t the whole story. Yes, there are many situations where creating biofuel from biomass does not make sense, but who said it was necessary to turn everything we see into biofuels? It makes a lot more sense to have biofuels compete from an economic standpoint, being farmed from areas of land where nothing else will grow, and from plants that cannot be eaten anyway. Many of the early biofuel adopters have also discovered another ready source of biodiesel: fast food restaurants. While this certainly will never provide enough biofuel to make a dent in worldwide demand unless we implement a strict diet of Happy Meals globally, it doesn’t have negative impact on the environment. The fuel is sustainably grown and is used for food initially. Only after the initial food utility is used up do we transform it into something that can power a vehicle as well.
There is plenty of room for other forms of biomass, as seen in the wood pellet-powered Precer Bioracer. The problem comes when we try to adapt our environment – in this case our farmland and rainforests – to meet the needs of our current technology – the internal combustion engine. If we adopted our current technology to suit our environment, we would create more sustainable system. Another great example of this is the Woodgas Solar Camp Stove available at H1KER. This stove can create the heat of a blast furnace using only dead twigs gathered off the ground, and powered by a small solar panel. The fuel sources are all right there in the environment. This innovative device doesn’t even require planting new crops, and instead uses ambient biomass – fuel that otherwise would stay on the ground and create a greater risk of wildfires – in a safe and productive manner. What could be more sustainable than that?
