VOA常速英语:UN Study Calls for More Debate on Biofuels

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A new report by the United Nations Environment Program says developing biofuels as a green energy option is beneficial only when countries adopt a sophisticated approach. The report has warnings for African countries, which are already struggling to cope with the loss of productive farmlands through drought and land degradation.

The study, conducted by UNEP's International Panel for Sustainable Resource Management, concludes that while biofuel production and use may appear to be a solution for cutting greenhouse gas emissions caused by burning of fossil fuels, some biofuels are much more climate-friendly than others.

The report says biofuels can lead to reduced emissions or worsen the problem. For example, the study says using ethanol fuel made from sugar cane, as practiced in some countries like Brazil, can lead to emissions reductions of up to 100 percent when substituted for fossil fuel. But making and using bio-diesel from palm oil on deforested land can lead to a significant increase in emissions when compared to using gasoline. 

Given that most biofuels today are made from food crops such as maize, wheat, sugar cane, vegetable and palm oils, the authors of the study say it is also important that the growth of the biofuel industry does not encourage unsustainable habits, such as using productive farmlands to grow energy crops.

UNEP's spokesman Nick Nuttall says far more research and debate is needed to determine which energy crops can grow where and how best to use limited land resources to combat climate change. He says other considerations include the impact of energy crops on such things as local water quality, quantity and biodiversity.

"Too much of a good thing can become a problem and that has to do with the fact that there is only a certain amount of land available on our planet," said Nick Nuttall. "Water supplies and some of the impacts on soil fertility, N20 [carbon] emissions - these are factors that need to be assessed."

David Newman, who runs the Nairobi-based biofuels consultancy Endelevu Energy, research and debate are especially critical for Africa, where sustainable land management and agricultural production efforts are often at odds with the need for development.

One of the most controversial local issues is the production of bio-diesel, which Newman says could be a disaster for some African countries trying to enter the market.

"Bio-diesel is, of course, based on virtually any vegetable oil, feed stock, and there are edible feed stocks and there are inedible feed stocks," said David Newman. "And that is very relevant in a place like Kenya, which is a net-importing country when it comes to edible vegetable oil. So, it would be potentially dangerous to base a bio-diesel industry on large-scale production of those feed stocks because it would be in direct competition with the deficit demand for food."

This week, Kenya's neighbor, Tanzania, announced that it was halting further land allocations for biofuel development until a framework to regulate the industry is in place.

The government move follows reports that arable land that could be used to grow food is being increasingly used for biofuel production.