The debate about biofuels is much wider than whether engines can be designed to operate using them (of course) and whether the car industry can be persuaded to get behind them (probably, if it's made worth their while).

As you alluded to briefly in your article 'Route of all good' (Focus, 3 July) but did not explore further, the attraction on the face of it is that this would allow large areas of agricultural land to be converted into a source of bio crops to sustain this new green industry.

It is obvious that the crops would have to come from somewhere. We either grow a significant proportion of what we need here or we import it.

The latter case would nullify one of the great arguments for this sort of alternative fuel source - that it reduces our dependence on overseas supplies and makes us more self-sufficient.

So if we are going to grow these crops we are talking about, we need a revolution not just in the UK's energy economy but also in our agricultural economy.

If you think that sorting out the transport and energy sectors is a major task, imagine the implications of converting a significant part of our farming industry to bio crops.

The big problem is that the future of agriculture in the UK is now thoroughly intertwined with what happens elsewhere in Europe - you only have to look at the constant rows over farm subsidies and mountains and lakes of this or that, where cash is given to support uneconomic production.

If biofuels really do turn out to be a massive, profitable industry for agriculture, can you imagine the rows about which part of Europe gets the benefits?

And if it is not profitable - but is pushed ahead anyway on environmental grounds - there will be massive new subsidies that will be necessary to maintain it, funded by the taxpayer no doubt.

R Banks



Biofuels are indeed going to play a big part in transport in the near future (Focus, 3 July) but renewable electricity can too.

I have been driving electric vehicles using grid-supplied wind and hydro energy for years, most recently charging my Citroen Berlingo Electrique - range 50 miles, top speed 60mph - using my own micro renewable generation.

Evan Tuer



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