Introduction
Over the past decade concern has grown over the environmental consequences of fossil fuels, this has influenced the recent interest in biofuels (Hill et al. 2006). Ambitious policies that promote biofuel use and production have not only been set by the EU, but by the USA and China as well (Soimakallio and Koponen, 2011). Biofuels are produced from processed food crops, other plants or animal products and agricultural or organic wastes. Crops grown specifically for energy uses rather than food or feedstock’s, are known as second generation biofuels, these are in development and not currently available for commercial use (Rowe et al. 2009). First generations biofuels are produced from processed food or feed crops, these are used today. Have brought conflict over growing crops for food, growing crops for fuel and protecting the environment.
What advantages are there to using biofuels?
Europe has few crude oil reserves and is highly reliant on imports to obtain fuel, 98% of transport in the EU is entirely dependent on fossil fuels (IPCC, 2011). Rising oil prices improve the cost competitiveness of biofuels helping them enter the market, providing a viable alternative for oil (Hill et al. 2006). European leaders see domestic biofuels as a more secure and sustainable option, providing incentives for more biofuel usage.
The aim of biofuel usage is to help combat climate change by reducing the greenhouse gas emissions that are currently released with the burning of fossil fuels by increasing its share of renewable energy (Banse et al. 2011). The majority of biofuels reduce greenhouse gas emissions by more than 30% when compared to fossil fuels combustion (Scharlemann and Laurence, 2008). When biofuels are blended with petroleum fuel or diesel they can improve air quality, especially in urban regions, as they generally bring a reduction in sulphur, particulates and carbon monoxide (Worldwatch Institute, 2006).
Liquid biofuels are important as they can be substituted immediately into the majority of transport vehicles. Meaning greenhouse gas savings can be achieved with little monetary investment or time developing new transportation infrastructure, making them a popular choice for governments.
Biofuels have the potential to provide environmental benefits, if they are planted on barren land where the soil has low carbon content, they can sequester carbon into the soil, effectively becoming a carbon sink. Moreover, if planted on this type of land they could increase biodiversity and protect watersheds, as they offer a more diverse and natural environment than other agricultural systems (Karta, 2006).
This is great: So what are the disadvantages?
The burning of biofuels can emit less CO2 than combustion of fossil fuel, the growth and production stage of biofuels needs to be taken into account. Have you considered your personal carbon footprint? Low yielding energy crops, such as corn ethanol, can have heavy inputs of fossil fuel energy during intensive farming and manufacture and can in some cases increase the environmental impact. CO2 is not the only greenhouse gas emitted during this process, N2O is also released, affecting the net greenhouse gas balance (UNEP, 2009).
Increase biofuel usage will subsequently lead to the demand for land needed to cultivate biofuel crops (Harvey, 2011). Clearing native ecosystems is sometimes the most profitable method of obtaining land, causing detrimental effects to water, soils and the regional climate (Tilman et al. 2009). An increase in ecosystem destruction rates will lead to a rise in biodiversity lost.
If biofuel production continues using the same intense methods of farming as have been used over the past century, it will increase the use of chemicals such as nitrogen, phosphorus and pesticides (Hill et al. 2006). These can enter habitats and aquifers, affecting the surrounding ecosystem, causing issues such as eutrophication. Current farming methods use a lot of water in the irrigation and processing of the crops. Biofuels compete with food crops for land space, this competition drives the prices of food up making it difficult to feed the world poor.
Conclusions
Global population has recently exceeded 7 billion (BBC, 2011), and is still increasing. Demand for energy is rising, and sources suggest that we are reaching our level of peak oil, implying that our reliance on fossil fuels cannot continue (IPCC, 2007). I believe biofuels can be used as a short term substitute. However they should not be considered as a long term alternative to fossil fuels, as it is not sustainable. The development of second generation biofuels, if produced sustainably could provide part of an alternative to fossil fuels, as they produce biofuels from waste products and energy grown crops. Yet they should not be completely relied on, as the impacts of growing the amount of biomass needed to replace fossil fuels would be too harmful to the environment.
If you are interested in finding out about the part other alternative energy sources, such as solar power, have to play in the future of energy supply have a look around the website.
References
Banse et al. (2011) Impact of EU biofuel policies on world agricultural production and land use. Biomass and Bioenergy (35) 2385-2390.
BBC (2011) Population seven billion: UN sets out challeneges, (Online). Avaliable: http://www.bbc.co.uk/news/world-15459643 . [Accessed: 24/11/2011]
Harvey, M. and Pilgrim, S. (2011) The new competition for land: Food, energy and climate change. Food Policy (32) S40-S51.
Hill, Jason, et al. (2006), ‘Environmental, economic and energetic costs and benefits of biodiesel and ethanol biofuels’, Proceedings of the National Academy of Sciences, 103 (30), 11206-10.
IPCC (2011) Special Report on Renewable Energy Soureces and Climaate Change Mitigation: Bioenergy. International Panel on Climate Change. Cambridge University Press: Cambridge, UK.
IPCC (2007) Mitigation of Climate Change. Chapter 4.3.1.3. Petroleum Fuels. IPCC Fourth Assessment Report: Climate Change.
Karta, S. (2006) Environmental effects of Bioenergy. Bioenergy and Agriculture: Promises and Challenages, brief 4 of 12.
Rowe, Rebecca, Street, Nathaniel, and Taylor, Gail (2009), ‘Identifing potential environmental impacts of large-scale deployment of dedicated bioenergy crops in the UK’, Renewable and sustainable Energy Reviews, 13, 271-90.
Scharlemann, J. and Laurence, W. (2008) How green are biofuels? Science, 319, 43-44.
Soimakallio, Sampo and Koponen, Kati (2011), ‘How to ensure greenhouse gas emission reductions by increasing the use of biofuels? – suitability of the European Union sustainability criteria’, Biomass and Bioenergy, 35, 3504-13.
Tilman, David, et al. (2009), ‘Benefical Biofuels – The Food, Energy and Environment Trilemma’, Science, 325, 270-71.
UNEP (2009) Assessing biofuels, United Nations Environmental Programme.
Worldwatch Institute (2006) Biofuels for transportation
