MENLO PARK, Calif., April 23 (UPI) -- U.S. scientists say biodiesel fuel won't drive down global warming and it might increase rather than reduce greenhouse emissions.
The researchers at California's SRI Consulting -- an international business research service for the chemical industry -- determined the use of biodiesel fuels will not make any difference to global warming and could result in greater emissions of greenhouse gases than from conventional petroleum diesel.
Analysts compared the emissions of greenhouse gases by the two fuels across their overall life cycles from production to combustion in cars. The results, said the scientists, show biodiesel derived from rapeseed grown on dedicated farmland emits nearly the same amount of greenhouse gas emissions as does conventional diesel.
However, if the land used to grow rapeseed was instead used to grow trees, petroleum diesel would emit only a third of the CO2 equivalent emissions as biodiesel.
Petroleum diesel emits 85 percent of its greenhouse gases when burned in an engine. By contrast, the researchers said two-thirds of the emissions produced by rapeseed derived biodiesel occur during farming, when the cropland emits nitrous oxide that's up to 300 times as potent as CO2.
The study appears in the journal Chemistry & Industry.
Copyright 2007 by United Press International. All Rights Reserved.
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