If you’re in Britain right now, you’ll probably be aware that it’s the new season of the Great British Bake-Off, the BBC’s TV baking competiton. It’s an unlikely television phenomenon, but phenomenon it definitely is, and everyone is talking about baking. This year 10:10 have challenged their supporters to create some low carbon bakes, and that got me thinking. Low carbon is one thing, but would it be possible to make a zero carbon bake?
I considered the slow cooker. I’ve heard of recipes for making bread or cake in one of those, and they reputedly use about the same amount of energy as a light bulb. But despite our 100% renewable energy tariff, that’s not zero carbon.
I considered the rocket stove, of which I am a big fan. Perhaps I could draw inspiration from my grandad’s wartime experiments. He found ways of baking with an old biscuit tin on a fire, which made him very popular with the rest of his tank crew. No doubt I could find a suitable tin, but cooking on scrap wood and twigs would be carbon neutral rather than zero carbon per se.
So how about using the sun?
We don’t have solar panels, and creating electricity and then turning it into heat is inefficient. Better to use the sun’s heat directly and do it the old fashioned way – with some shiny cardboard and a Kilner jar painted black.
My first attempt didn’t go well. It clouded over and rained on my banana bread. Take two was much more encouraging. Here’s the result:
I wouldn’t suggest baking a big cake this way, but I reckon there would be a way of doing cupcakes in a tray. But perhaps, given the way the weather looks this week, I’ll have to wait until next summer to try it.