Sir, There is no need for UK to use palm oil for fuel ("Biofuels ‘more polluting than diesel’," Mar 1) If the area that used to be “set-aside” in UK was used for oilseed rape this could potentially provide the basis for up to 5 per cent of our diesel requirement. A large volume of used frying oil could also be integrated, reducing noxious waste.

Nigel Earle
Northampton

Sir, In this discussion it is remarkable that potentially the most efficient biomass crop is never mentioned. Palm oil, sugar cane, cornstalks, rapeseed, soya, kenaf, but never a word about hemp. It is extraordinary that a taboo on that word, because of its association with cannabis (which is only one type among the many varieties of the plant), should preclude this crop from consideration in view of its many advantages. It is the fastest-growing crop on Earth, producing two or even three crops a year in some hot countries, it will grow almost anywhere, on land that is unsuitable for most other crops (thus reducing the need to clear forests), it has virtually no predators and thus requires no chemicals to grow it.

Joe Mellen
London SW9

Sir, After soliciting opinions from 300 “experts” (presumably without any well-informed algologists, photobiologists or plant biochemists among their number) the UK’s Carbon Trust has created an Algae Biofuel Challenge, a £16 million fund to support the development and large-scale production of algal oil. Sadly, this initiative disregards half a century of worldwide research and the constraints imposed by the laws of physics. It is based on the belief that microalgae are ten times as productive as other “plants” even though there is no evidence that cultivated algae are able to accumulate substantially more biomass, during a period of sustained growth, than other green organisms. When comparisons of productivity are based on the normal period of growth, the yields of biomass are similar, regardless of species or locality.

Intensive agricultural practice of any sort rarely uses less fossil fuel energy than the solar energy that it conserves as biomass. Biofuels do not, therefore, lead to an appreciable sparing of carbon dioxide emissions that could not be better accomplished by the most modest means of energy conservation.

David Alan Walker
Emeritus Professor of Photosynthesis, University of Sheffield

Sir, Your report makes a valid point that when biofuels are not sourced sustainably negative effects can occur. However, studies relating to the area of indirect land use change show that the science is clearly lacking to support any broad statement that all biofuels are more polluting. The NFU believes that all policy should be led by the credible science that is available but clearly on this issue the science is lacking.

We support the development of sustainable, British biofuels that could be grown under farm assurance. This could help this fledgeling renewable industry to establish itself, creating green jobs, and to reduce our reliance on fossil fuels and carbon emissions from transport.

Using conventional crops for biofuels is not necessarily “food v fuel” but production for both food and fuel. Up to half the feedstock used in biofuel production is retained as a co-product and can still be used as animal feed. Using conventional crops for biofuels also maintains arable production capacity and provides an easy option to return land to food production.

An important indirect effect of the Renewable Energy Directive is that it will be a driver of sustainable production as a result of the mandatory criteria creating a market that values sustainability.

The ILUC (indirect land use change) studies, as well as failing to be able to show how commodity markets interact, also fail to show the impacts of the sustainability criteria at the heart of policy. A review of these targets would set Britain back decades in reaching renewable energy targets.

Ruth Digby
Biofuels adviser, NFU

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