Well, it's not exactly elegant, but it's low emission, high efficiency, and the wood doesn't need to be processed at all. It'll basically look like a big metal barrel. They used them a lot in World War II. Usually they're mounted on a small trailer hooked up to the front or back of the car, but it might be possible to fit it in the trunk. Or, uh, the boot. [He grins. It is a Bentley, after all.

(Wow, historical context and knowledge of regional linguistic variations? Yeah, well, don't get too impressed: he literally only knows those things because they have to do with engineering and cars.)]