Zulu, don't know if you've heard of a book "Home-Grown Energy from Short-Rotation Coppice" by George MacPherson (mine is dated 1995). It covers planting and harvesting willows (and maybe poplar i think) then selling on as wood-chips as an alternative (and much cheaper) ongoing source of energy.
It's the sort of thing that looks a bit like too-much trouble for most of us but a bloke I worked with in the past swore by it as being profitable, and certainly a highly ethical way of making money!..GB
just dug it out..ISBN 0-85236-289-7 if interested
Happiness is a journey, not a destination,
so Work like you don't need the money,
Love like you've never been hurt,
and Dance like no one's watching..