Recently, more than a few people have started voicing their concerns about the benefits of biofuels being not all they are cracked up to be - read this article for a blistering critique of biofuels on environmental grounds.

So it's intriguing to see that D1 Oils is playing up the point that " . . . it is careful to ensure that jatropha does not replace food crops for farmers in Zambia, and it does not plant in nature reserves or protected areas".

It's all about trade-offs. I don't doubt that replacing vast swathes of forest or untouched land with monoculture biocrops would yield a net decline in biodiversity. Yet Brazil has shown how their ethanol programme has saved a great deal of cash being spent on imported oil - apparently profitable with oil in excess of $30 a barrel. This of course gives them more money to do other things, perhaps even save rare species.

This debate is also nothing new. When Julius Caesar arrived in Britain in 54 B.C., he proclaimed the country to be one huge, horrible forest. Today, it is perhaps just 10%. Civilisation started with agriculture because it required order, many additional divisions of effort and above all credit. Debts were incurred for the first time because crops could only be produced once a year. In return for protection of the farmers, hunter gatherers could look forward to a steady supply of food.

Anyway, I digress. The point is this - until (and if) the cost breakthrough is made with cellulosic biofuels, the world will need a lot of land to grow the biofuel feedstock crops. The demand is just too great not to do otherwise.