hmm you just dry them as and when you have the radiators on dont put the heating on just to dry them that would be silly :-D
Yeeeaaarrrrggghhhh!
That's exactly the kind of woolly thinking that scares me about my race.
What's the point of turning on the heating if you're then going to COOL the place by evaporating gallons of water?!
You can't beat physics. If you turn water into vapour it absorbs heat. The water vapour then leaves the premises by the nearest exit, taking the heat with it. You're paying for that heat. And so, as we finally seem to be realizing, is the planet.
The only way to avoid this (partially) is to exhaust all the air from the building through a heat exchanger which is COOLED by a heat pump. The heat can then be recovered. You can get about five times as much energy from a heat pump as it uses, so this way you can cut your heating bills by about 80%. Unfortunately, compared with the old-fashioned ways, heat pumps are expensive, complex and unreliable -- but as energy costs continue to increase, they become more and more attractive. You seem them everywhere in the USA and Europe, but I'm afraid in the UK we're some way behind.
Condensing boilers work on the same lines, which is why they're much better than those from the last century. They've started to appear in the UK, that's a small consolation.
mine dry out quick in the greenhouse
As long as it's only heated by the sun, that's the way to do it!