Life Cycle Analysis Fuels Biofuel Dispute
June 13, 2012
Study: Environmental Benefit of Biofuels is Overestimated
R&D Daily (June 10, 2012)
In the words of Kermit the Frog, "It's not easy being green." Paper or plastic? That's easy (kind of): Neither. Bio- or fossil fuels? "Neither" isn't a realistic option when it comes to energy.
Many years ago I did several client studies on the environmental impact of electric vehicles. This was at a time when electric cars were proclaimed to be the solution to urban smog, and measurements were mostly done on "out the tailpipe" emissions. After a lot of desk research, I started talking with industry and government scientists, legislators and representatives of environmental groups such as Greenpeace.
Long story short: the tailpipe is just the most visible, mobile component of total emissions. When you do a Life Cycle Analysis, taking into account the emissions of the stationary sources that manufacture the batteries, the disposal requirements of spent batteries and the limited range of the electric vehicles necessitating a second car in most cases, the picture becomes less clear.
The crux of the study is how you use Life Cycle Analysis to model the greenhouse gas emissions of bioenergy production. Another long story short: critics of current calculations say that ignoring the emisisons of CO2 by vehicles using ethanol and biodiesel overestimates the benefits of these biofuels over fossil fuels. The article goes on to explain why nitrogen emissions from fertilizer use also needs to be taken into account, and offers another option that doesn't compete with crop production for food, textiles and other products.
P.S. The obvious answer to opting for neither paper nor plastic at the supermarket is, of course, your own reusable bag. However, experts warn that your own bags start harboring all sorts of nasty stuff if you don't wash them frequently or ignore meat juices that may have leaked into the material.
Categories: June 2012; Enigmas and Tough Challenges
Topics: Ecology; Green; Transportation
Study: Environmental Benefit of Biofuels is Overestimated
R&D Daily (June 10, 2012)
In the words of Kermit the Frog, "It's not easy being green." Paper or plastic? That's easy (kind of): Neither. Bio- or fossil fuels? "Neither" isn't a realistic option when it comes to energy.
Many years ago I did several client studies on the environmental impact of electric vehicles. This was at a time when electric cars were proclaimed to be the solution to urban smog, and measurements were mostly done on "out the tailpipe" emissions. After a lot of desk research, I started talking with industry and government scientists, legislators and representatives of environmental groups such as Greenpeace.
Long story short: the tailpipe is just the most visible, mobile component of total emissions. When you do a Life Cycle Analysis, taking into account the emissions of the stationary sources that manufacture the batteries, the disposal requirements of spent batteries and the limited range of the electric vehicles necessitating a second car in most cases, the picture becomes less clear.
The crux of the study is how you use Life Cycle Analysis to model the greenhouse gas emissions of bioenergy production. Another long story short: critics of current calculations say that ignoring the emisisons of CO2 by vehicles using ethanol and biodiesel overestimates the benefits of these biofuels over fossil fuels. The article goes on to explain why nitrogen emissions from fertilizer use also needs to be taken into account, and offers another option that doesn't compete with crop production for food, textiles and other products.
P.S. The obvious answer to opting for neither paper nor plastic at the supermarket is, of course, your own reusable bag. However, experts warn that your own bags start harboring all sorts of nasty stuff if you don't wash them frequently or ignore meat juices that may have leaked into the material.
Categories: June 2012; Enigmas and Tough Challenges
Topics: Ecology; Green; Transportation