[JockoT]

As the overnight temperatures start to tumble (it isn't even officially autumn yet) I think a block heater would make a lot of sense. This morning I drove my wife to her work, two miles there, two miles back, and the car didn't get up to even approaching operating temperature.
My question is, could I run a block heater off an auxiliary battery and inverter?
I would take the battery into the house during the day, and charge it from the mains, then return it to the garage at night, to run the block heater. I would require some sort of battery operated timer (run from the car battery to avoid having to constantly reset it), but that, the inverter and the block heater would be a permanent fixture on the car. I would just need to connect the battery to a plug on the car.
My garage is provided by the county, is remote from my flat, and has no provision for power.
What do you guys think? Any better suggestions? All ideas welcome.