Biofuels are in principal a carbon neutral renewable energy source derived from organic matter (predominantly plant matter) that can be used as an alternative to fossil fuels. When plant derived biofuels are burnt, the released CO2 is offset by the amount of gas absorbed by the plants when they grew.

With growing concerns about the lack of land to produce enough food and biofuel, further developments in biofuel technologies such as ‘second generation biofuels’ could solve the problem.

Second Generation Biofuels - Definition

Second generation biofuel technologies use biomass, meaning any plant-derived material, as a feedstock. This type of biofuel could help alleviate the problem of food production versus fuel production and reduce waste sent to landfill in the UK as it broadens the scope for feedstock supply.

With UK food retailers estimated to be generating and disposing around 500,000 tonnes of food waste a year, according to Biffa Waste Service, by using second generation biofuel plants, retailers could produce a vast amount of renewable energy and drastically reduce the amount of waste send to landfill, therefore reducing the amount of methane produced.

The chief executive of Infinis, a company that claims to be the UK’s largest purely renewable energy generator, believes that the waste from one UK supermarket group could provide as much as 5 megawatts of energy - enough to power 10,000 homes. This highlights the vast amount of untapped energy that the UK is sending to landfill without ever harnessing the energy.

Second Generation Biofuel Production

Currently (September 2007) there are no second generation biofuel plants in planning or construction in the UK. However, globally there are a large number of projects in planning and under construction for second generation biofuels, predominately in the USA and Europe.

Advantages of Second Generation Biofuels

The advantages to second generation biofuels compared to first generation biofuels are that they are generally more efficient and more environmentally friendly. Less farmland is required to grow the same amount of feedstock, because the whole plant can be used instead of just the grain or oil, and food crops are not used up as it uses any part of the plant. A mixture of crops can be used, which generally requires less fertiliser and has less impact on biodiversity. Also, useful by-products are produced which can be used in other chemical processes or burned for heat and power.

However, in some areas of the world, first generation processes can be extremely useful and can provide a good, environmentally-friendly fuel supply. This occurs in situations where there is a surplus of cheap raw materials, which can be grown without having a detrimental effect on the environment or habitat. For example, Brazil grows a lot of sugar cane without harming the environment with fertilisers. This has enabled Brazil to produce 23% of all its energy from natural fuels, compared to the World’s natural fuel use of just 1.7%.

The Effectiveness of Biofuels

Biofuels are very popular in the USA, Brazil and much of the EU because they are able to help countries meet their emission targets and become more self-sufficient.

However, there is a growing opinion that biofuels are not the quick fix that they were once believed to be. The effectiveness of biofuels has come under question. Almost all biofuels offer some carbon savings, because the carbon dioxide (CO2) that is emitted into the atmosphere when they are burned is offset by the amount the crop absorbed as it grew.

It is important to note that the carbon savings from biofuels must be offset by the energy that is needed for cultivation, harvesting, processing and transportation. The most effective biofuels are those that are produced using the least energy (e.g. low inputs of fertiliser, processed in an energy-efficient way and transported short distances).

On the contrary, the worst biofuels can result in greater lifecycle carbon emissions than fossil fuels (i.e. more energy is needed to produce them than is saved by using them).

According to the Department of Transport, most biofuels offer a carbon saving of around 50% compared to fossil fuels. If the UK was to achieve its 5% biofuel sales target, this would deliver a carbon saving from road transport of around 2.5%, which would equate to about 1 million tonnes of carbon per year, this is the equivalent to taking a million cars off the road (Source: Department of Transport).

Potential concerns

There are other considerations that need to be taken into account when addressing the effectiveness of biofuels regarding greenhouse gas (GHG) emissions reduction. A study published in Atmospheric Chemistry and Physics, found that biodiesel derived from oil seed rape (OSR) and maize (corn) produced up to 70% and 50% more GHG emissions than fossil fuels. The concerns were over the levels of nitrous oxide being emitted, a gas that is 296 times more powerful than CO2 . With 80% of biofuel production in Europe coming from OSR there could be a need to research the effectiveness of biofuels more.

Other concerns surrounding biofuels are the cost of raw materials; within the UK feedstock’s costs are generally higher (especially compared to Brazilian bioethanol) than in other countries. Due to the high costs UK farmers may only benefit if cheaper imports become less available owing to growing global demand.

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