I've just received an electric fan for the radiator from Centerline.
This includes the means to secure it to the rad, as well as a thermostatic on-off switch that is adjustable.
At first I thought I would install it on the inside as a puller, but over some wine last night--well enough to provide the foundation for brilliance-- I came up with THE idea.
Mount it on the front and and when the thermostat does not have it engaged for cooling, the air flow will drive it like a windmill. With likely simple wiring this will generate current into the system.
I'm sure that Gordon or Terry would have some advice on the details.
The mind boggles at the opportunity of not only turning hydrocarbons into fabulous exhaust sounds, but also being able to turn the kinetic energy into electrical power.
All the those "carbon credits" to be gained and it would likely offset at least one and a half people's worth of guilt just for living on the planet.