Coming from an engineering background, I was pleased to see that the only realistic alternative to fossil fuel for transport, namely biofuel from non-food crops, is at last attracting serious attention (8 December, p 34).
It was interesting to note, however, that most of the projects described are based in the US, with its high proportion of vocal climate change naysayers. Where are the UK projects that use, for example, waste heat from power stations to accelerate algal growth, or indeed, hot air from Westminster, home to Parliament?
From Almuth Ernsting, Biofuelwatch
Claims of "carbon negative" fuels rely on the assumption that adding biochar residue to soils will store carbon over the long term and improve soil fertility.
The evidence for this is far from assured. The small number of biochar field trials show that adding it to soils might not increase soil carbon at all, even in the ...
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