It is really quite marvellous how all of these various things we're supposed to be doing to save the planet are exactly the things we used to do which damaged the planet so badly. As Matt Ridley points out when talking about what we're supposed to do to keep warm when we can't burn coal or oil:

To replace coal, the government projects that by 2020 Britain will be generating electricity from burning up to 60m tonnes of biomass, mainly wood, about five times the timber harvest that Britain could conceivably produce.

Now "five times the harvest we could possibly produce" means that we would be over using that resouce. Denuding these islands of trees in fact. Which is what we actually did do all those centuries ago and what impelled us to go and conquer a quarter of the world in order to gain resources (no, really, we did things like go to war against Denmark so that we could have access to the Baltic timber to replace what we'd burnt) and also to start digging up coal in the first place.

Because there was no wood left, see?

It may well be that out there somewhere is the technology that can wean us off coal but it's almost certainly not going to be the one that we abandoned to embrace coal in the first place , is it? For the clear and obvious reason that the last time we did it there wasn't any wood left which is why we stopped doing it.

Guys, you know, "Forward to the Middle Ages" is meant to be a joke about the more extreme greenies, not a blueprint for the government to follow.