Willow as a Biofuel

[Segilla]

Obviously it works, but on the face of it, even on extensive 'farms', the rate of growth seems inadequate to produce enough material to make it worthwhile compared with say coal which is mined by the thousands of tons.
Does willow burn more slowly, give off greater heat?
A few words pf explanation wouild be welcome.

[RATTER15]

Well willow is renewable and coal isnt, willow grows very quickly and readily but would still take a lot of willow to be viable I would think!!

[heathfield]

I read an article recently that showed that if the whole world turned to biofuels alone, one third more of the world's surface would have to be put to agricultural use than is available at present.

[Mortartube]

I can't speak for the burn rate of willow as a biofuel, but I believe that it has quite a pourous structure, and when made into charcoal, the charcoal produces one of the fastest gunpowders available. Balsa wood being even better. It burns rapidly and with a great deal of heat.

[jake-the-peg]

Wood pellets are 13.5 Million BTUs per tonne 46% less than coal.

Drax power station uses about 3 million tonnes of coal a year

so that's nearly 5 million tonnes of wood a year.

You can produce 2-12 Tonnes of fuel per hectare per year be generous say 10 that's 300,000 Hectares.

The problems are drying that amount and the fact that it's a very low value crop with coal at �30 a tonne that's �192 a hectare delivered to the powerstation

with wheat at say �100 per tonne with say 6 Tonne per ha

see:
http://www.blt.bmlf.gv.at/vero/veroeff/0345_Pr oduction_of_willow_e.pdf

and

http://www.nfuonline.com/x9763.xml