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Burning questions about biofuels

Biofuel enthusiasts, including the new US president, say food crops can provide a cleaner, greener source of energy than fossil fuels. Yang Fangyi urges caution.

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The new president of the United States, Barack Obama, has planned a range of measures to deal with climate change. These include the expansion of the use and production of biofuels. But while biofuels can replace some fossil fuels, the main focus of climate-change mitigation should be reducing fuel consumption and increasing energy efficiency. Biofuels cannot be a major part of the solution – and they may have a negative impact on the climate and the global economy.

Simply put, any organic substance converted into fuel is a biofuel. “First generation” biofuels are already widely available. These include ethanol produced from food crops such as maize, sugarcane and sorghum, and biodiesel from oil-bearing crops like soybeans, oil palms or rapeseed. Tung-oil trees have also been planted for use as biofuel feedstock. Research into “second generation” biofuel technology is also underway. This would mean converting wood cellulose directly into fuel, but the manufacturing processes have not yet advanced to the point where this is possible.

In 2007, 53 billion litres of ethanol and 10 billion litres of biodiesel were produced. However, the cost of planting crops for feedstock is high, and production is rarely profitable or able to compete with oil. In July 2008, with oil prices at a record high, a litre of unleaded petrol cost US$1.08 in the US. At the same time, a litre of maize ethanol still cost almost US$1 to produce. The current downturn has seen the cost of petrol drop to around US$0.44 a litre, meaning biofuel alternatives are even less competitive. The high costs of biofuel production mean that governments are forced to provide subsidies. Currently the only profitable biofuel is the sugarcane ethanol produced in Brazil.

Of most concern is the impact of biofuels on global food security and agriculture. Large areas of farmland are being used for biofuel feedstock production instead of food crops, which raises the price of staple foods. Biofuel expansion is not the only factor behind recent price rises, but it is a major one. Many developing countries are unable to buy enough food – and there is a real threat of starvation for the poor. This has led some to describe the use of food crops for fuel when people are going hungry as a “crime against humanity”.

In theory, biofuels are carbon neutral: burning crops emits the same carbon dioxide that the plants took from the atmosphere during photosynthesis. But in practice, the situation is not so simple, because planting feedstock, processing biofuels and transporting them all require additional energy inputs. A 2008 report from the Organisation for Economic Cooperation and Development (OECD) found that production of sugarcane ethanol in Brazil did reduce emissions by 80% when compared with fossil fuels. However, maize ethanol production in the United States cut emissions by less than 30%. The environmental impact of this first-generation technology was overestimated.

It is also incorrect to assume that planting biofuel feedstock does not cause greenhouse-gas emissions. Tropical forests – crucial carbon sinks – are being devastated as land is cleared for biofuel production. The creation of fields for the planting of soybeans and sugarcane is a cause of deforestation in the Amazon rain forest. Rain forests in Indonesia are being cut down and replaced with oil palm plantations. A paper published last year in the journal Nature described how a “carbon debt” is created, as the destruction of forests often releases more carbon dioxide than is saved by replacing fossil fuels. Environmentalists are also worried by the deforestation occurring in biodiversity hot spots in the Amazon and southeast Asian rain forests. 

Planting biofuel feedstock results in soil loss and water pollution. Soil degradation caused by large-scale fertiliser use is also a prominent issue, and the nitrous oxide released by fertiliser use is a greenhouse gas many times more powerful than carbon dioxide.

First-generation biofuel technology has not provided the environmental benefits its proponents hoped. On the contrary, it has brought its own environmental risks. The European Union has started to make changes to its biofuel policy, and members of the European Parliament voted to reduce the target for biofuel use from 10% of transport fuels down to 6%, and establish a system of certification for sustainable biofuel production. The new US president is starting to take biofuel development seriously: Obama says he hopes to harness the power of second-generation biofuels technology. But it is not yet clear if this technology will be profitable, and biofuels cannot be relied on to reduce greenhouse-gas emissions. The key to achieving that aim will be increasing energy efficiency and expanding environmentally friendly energy sources, such as wind and solar power.

Yang Fangyi is a masters student at the Tropical and International Forestry Institute, University of Gottingen, Germany. Between 2004 and 2008, Yang worked on biodiversity preservation projects for Conservation International in China. He also worked for the Shan Shui Conservation Centre.

Homepage photo by net_efekt

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Default avatar
匿名 | Anonymous

云南麻疯树

中国正在摸索在其边疆少数民族聚居区种植生物燃料的可行性 ――在云南推广麻疯树,在新疆推广黄角花。但是至少已有一项知名的研究对这种做法的商业价值提出了质疑。另外,那些推动这些项目的人并不在意这些项目对当地原住民生活的负面影响。毕竟这些项目的融资部分出自香港和多伦多的证券交易所。(那样更能让当地人觉得这些投资活动是“国民义务”而不是强征土地或是出于政治动机的行为)

本文由CHEN fangfang翻译

Jatropha in Yunnan

China is speculating that cultivation of biofuel crops will be viable in border regions characterisedd by ethnic minorities - in Yunnan (with Jatropha) and Xinjiang (with Yellowhorn).

At least one reputable study questions the commercial rational for such land-use change.

Further, the adverse impact on the livelihoods of those regions' indigenous peoples is of little consequence to those who promote such projects - (risky) finance for which is raised partly from stock exchanges in Hong Kong and Toronto (the better to impress local people that the ventures are "national imperatives" rather than either a land grab or for political advantage).

Default avatar
匿名 | Anonymous

同意1号

看来,面对媒体对生物燃料的大力宣传,公众需要重新加以认识!

I agree with No.1

It seems that the media promotes biofuels vigorously, so the public needs more understanding!

Default avatar
匿名 | Anonymous

DG

与太阳能等其它可再生能源相比,生物燃料耗费大量的水。在考虑一种替代能源时,我们不仅应该看到二氧化炭的减少,还要考虑其他的环境因素。在中国水资源已经得到极度的开发利用,工业、农业、家庭生活者都在相互“抢水”。现在河流面临干涸,增加另一个用水者后将会是何种景象呢(指生产生物燃料)?
(本评论由田亮翻译)

Biofuels - high water footprint

Compared with other renewable energies like solar energy, biofuels have an extremely high water footprint. In considering an alternative energy we should not only look at CO2 reduction but also other environmental factors. Industries, Agriculture and household users are competing for water resources, which are heavily exploited in China already. Rivers are now running dry. What will be the consequence of adding another major water user (for producing biofuels)?

Default avatar
匿名 | Anonymous

新能源

太阳能和风能并不是在任何地方、任何情况下都能用的,现实地看,未来很长时间内石油和煤还是主要的能源选择。

New energy

Actually,Solar and wind energy cannnot be used in any place and in any circumstances,and oil and coal are still the major energy choice in the long future. (Translated by Tian Liang)

Default avatar
匿名 | Anonymous

中国农村

与以前相比,在农村很多农民逐渐富裕起来了,纷纷盖起了楼房。近几年在政府的宣传引导下,不少人家用上太阳能、沼气,方便生活而且节约了生活开支,这是一个很好的现象!

Rural Areas in China

Compared to previous times, many farmers in rural areas have gradually become more affluent and have built new buildings. After several years under the guidance of the government's propaganda many people now use solar energy and biogas, which has brought more convenience to daily life and saved on the cost of living. This is a very good phenomenon! (Translated by Tian Liang)

Default avatar
匿名 | Anonymous

那怎么办?

看了这个报道,我不由地倒吸一口冷气!

生物柴油项目,在作者眼中,竟然如此一文不值!

那我倒要请教,到底有什么实质性的做法可以减少地球变暖,可以减少环境污染?我希望能得到实质性的答案。至于所谓的提高能源利用率,实在是泛泛而谈!而开发太阳能风能,虽说很好,但是,并不是每一个地方都适合开发风能和太阳能的。
最后,我要说的是,种植生物能源树种,总比开挖煤炭好很多吧?

What should we do, then?

After reading this article I couldn’t breathe properly! In the author’s eyes, biofuel projects are totally worthless, in spite of everything! Now in response I must ask, ultimately what substantial practice can stop the planet from getting warmer, and can reduce environmental pollution? I hope to receive a substantial answer. As far as the so called rate of increasing energy use, really this is broadly speaking! Solar energy and wind energy, even though they are both very good, they cannot be developed in every place. Ultimately, what I’m trying to say is, planting biological energy and trees will always be better than excavating coal, right? (Comment translated by Michelle Deeter)

Default avatar
匿名 | Anonymous

回六楼

第一,本文讨论的是第一代生物燃料。有充分的数据说明第一代生物燃料目前减低气候变化和由毁林带来的二氧化碳释放的作用被高估了。所以,毁林种植生物燃料是得不偿失。欧洲2008年底已经通过对生物燃料进行认证的法案,希望是个对毁林是个约束。
第二,应对气候变化的主要答案是什么?UNFCCC已经谈了很多年,相信从谈判中可以去寻找答案。
第三,提高能源效率的确是个很宽泛的概念。不过刚看到绿色生活的广告,一个小小的节能灯每年都能带来那么大的效益。从小事做起,我们是有希望的,而不是用制造问题的方法来解决问题。

达瓦仁青

Feedback to sixth floor.

Firstly, this article discusses first- generation biofuels. The data is enough to confirm that the planting of biofuels has been overestimated for its impact in minimising climate change and reducing the release of carbon dioxide created by deforestation. Therefore, deforestation and biofuel planting is not worthwhile. At the end of 2008, Europe already began testing biofuels. I hope this results in deforestation restrictions.
Secondly, what is the principal answer to climate change? The UNFCCC has been discussing this for many years and I believe that these discussions can provide an answer.
Thirdly, the concept of increasing energy efficiency is very broad, but I have just seen the advertisement for green living, a tiny energy saving light bulb can bring so much benefit year on year. There is hope if we begin with small things, and don't create more problems when trying to solve old ones.

Default avatar
匿名 | Anonymous

不要仓促作出结论

的确,不负责任的生物燃料决定能对全球的环境和经济产生不利影响。当第一代生物燃料的理论影响,包括对土地使用的影响都改变时,一些研究甚至得出这样的结论,用玉米制造的乙醇结果在排放二氧化碳。
以垃圾和农业废物为基础的生物燃料没有这样的作用,但他们必须谨慎安排,以免其他养分循环失去平衡。这些液体燃料也将与农场废物生产的“生物电” 在经济上竞争,这一决定可能必须以政策为基础,同时考虑到国家能源安全的需要,以及发展这些不同类型的能量(注意:新一代燃料在商业上尚未存在)对整个环境和经济影响。我同意,效率是最重要的。生物燃料应被当作从运输到可再生能源发电的过渡时期的燃料,他们应该充分考虑所有可能出现的环境和经济方面的影响。Rob Earley, iCET (罗伯特, 能源与交通创新中心)

Don't make hasty conclusions

It is true that irresponsible biofuel decisions can have adverse effects on the environment and global economy. When including the theoretical impacts of first generation biofuels including indirect land use change, some studies even conclude that corn-based ethanol, for example, results in net emissions of CO2.

Biofuels based on wastes and farm wastes do not have this kind of impact, although they do have to be managed carefully so as not to throw other nutrient cycling off balance. These liquid fuels would also have to compete economically with "bioelectricity" produced from farm wastes, and this decision would most likely have to be policy-based, taking into account national energy security needs, and the overall environmental and economic impacts of developing these different types of energies (note that next-gen fuels do not exist commercially yet).

I agree that efficiency is most important. Biofuels should be seen as a transitionary fuel as transportation progresses towards renewable electricity, and they should be developed in full consideration of all the environmental and economic impacts that might arise.
Rob Earley, iCET (罗伯特, 能源与交通创新中心)