Seen by many as the solution to the problem of fossil fuels and increasing greenhouse gas emissions, biofuels have been heralded as clean and green. However, is this really the case, or do the headlines hide a darker truth?
What are biofuels?
Biofuels are made from organic matter, produced either by agricultural processes, anaerobic digestion or from converted biomass. There are two main types: biodiesel and ethanol.
Biodiesel is chemically similar to diesel; but is made from vegetable oil, soybean oil or animal fats. Bioethanol is made from fermenting starchy plants such as maize or wheat.
What’s the problem?
Biofuels have been widely promoted as being carbon neutral; it was believed that the carbon dioxide (CO2) released by burning the fuels was offset by the CO2 taken in by the crops through photosynthesis. However, a 2016 study found that CO2 produced was only offset 37% by the photosynthetic processes of the crops . Also, clearing land of high biological importance to produce biofuel crops creates up to 420 times more CO2 than the yearly savings which biofuels provide . A report by the independent group Transport and Environment estimated that by 2020 6.7million hectares of land will be cultivated for biofuel crop production in Europe alone in order to meet current EU renewable energy targets. This would release approximately 1bn tonnes of CO2 equivalent.
Across the globe, new biofuel plantations are leading to mass deforestation. Developing tropical countries are worst affected as the lucrative nature of biofuel crops and favourable climates have resulted in swathes of primary forest being felled to make way for plantations (Figure 1) . These tropical areas tend to be biodiversity hotspots which means the destruction of natural habitats have even greater effect and leads to higher rates of species loss as the ecosystems are all in a delicate balance . Once forest ecosystems are lost or fragmented, species are either forced into unsuitable habitats where they struggle to survive or into settlements which can lead to conflicts with humans. Similarly, the creation of large scale plantations greatly reduces the natural diversity of forests. Monocultures are far more susceptible to rapid spreads of pests and disease which can decimate crops and have huge implications for the communities which rely on them.
One of the most controversial issues in conservation today is that of palm oil. There is a huge global demand for palm oil which is increasing; the WWF estimates that by 2050, 240 million tonnes of palm oil will need to be produced a year. Palm oil is used in many everyday products, from cosmetics to cooking oils, as well as in biofuels. Palm oil production has contributed to mass deforestation; in Southeast Asia 45% of palm oil plantations were forested as recently as 1989 . The areas most threatened with biodiversity loss are those with most to lose; forests in Southeast Asia, South America and Africa, among others, are being felled in favour of palm oil. These areas are incredibly species rich and of high conservation concern . As demand for biofuels increases it is feared that even more biodiversity will be lost to palm oil (Figure 2).
Social and economic impacts
Not only do biofuel crops cause reductions in biodiversity, but they have been widely linked to food insecurities. During the first half of the 2000s biofuels rapidly gained popularity and there was a run on crops which could be used to produce bioethanol. The crops targeted were traditionally food crops such as sugar cane and grains. The rising popularity of biofuels led to an increased sale of these crops for biofuel production over food, thus leading to increased food prices and reduced food security (Figure 3) . These crops are termed ‘first-generation biofuels’ and in light of the issues encountered an effort has been made to move away from food crops to cellulose energy crops, such as willow or crop by-product wheat straw which are being referred to as ‘second-generation biofuels’ . In 2015 the European Parliament Environment Committee committed to capping the amount of food crops used for fuel at 6% of the targeted 10% renewably sourced energy by 2020.
However, second-generation biofuel crops aren’t without issues; there are monetary incentives to biofuel crops which make them more attractive to growers thus leading to reduced food crops. Similarly, although the implementation of second-generation crops was supposed to reduce the food versus fuel problem, the situation becomes less clear-cut when the issue of animal feed is included. Frequently, second-generation biofuel crops are constituents of livestock feed and their reassignment to biofuel production introduces new conflicts .
Additionally, there is growing concern over the impacts of second-generation energy crop farming in developing countries; biofuel crops can give developing countries export opportunities, reduce their reliance on imported energy and provide poor communities with income. However, agricultural intensification in developing areas not only threatens local people with disposition and loss of livelihoods but also threatens the local ecology as intensive agriculture can lead to habitat loss, acidification, and loss of soil quality and eutrophication of water through pesticide leaching.
Looking to the future there is a need to evaluate the place biofuels have in energy production. While biofuels do provide a viable alternative to traditional fossil fuels it is not without a price. Careful consideration of social and environmental impacts of biofuel crops must be made before they are deemed effective alternative technologies. It is important also to assess the sustainability of biofuel crop sources to conserve maximum biodiversity. It may be that biofuels come at too high a price and the future of energy production lies with wind and solar instead.
- DeCicco, J., M., Liu, D., Y., Heo, J., et al (2016) Carbon balance effects of U.S. biofuel production and use, Climate Change, 138, 667-680
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- Danielsen, F., Beukema, H., Burgess, N., D., et al (2008) Biofuel plantations on forested lands: Double Jeopardy for biodiversity and climate, Conservation Biology, 23, 2, 348-358
- Vijay, V., Pimm, S., L., Jenkins, C., N., et al (2015) The impacts of oil palm on recent deforestation and biodiversity loss, PLOS One, 11, 7, doi:10.137
- Mohr, A., and Raman, S., (2013) Lessons from first generation biofuels and implications for the sustainability appraisal of second generation biofuels, Energy Policy, 63, 114-122