are there any practical things we can do with hot radiator water ?
 

its easy to divert the coolant hoses in a car -the veg oil diesel guys have taught us that.

what *practical* things can we do with hot water for energy saving?

Put it in a thermos and release it again on next start-up.

what about heating up lots of water with a heat exchanger and then using that water for heating your house?

You think there is THAT much heated water?

how could that be retro fitted to a car? could we re-route the coolant hoses to a big 10-20litre insulated tank in the trunk or passenger foot-well?

obviously we would need to add more storage for the home heating idea

That could be. I don't think 10-20 l will cut it. Imagine a 5 gal pail of boiling water in your house. I don't think there's an appreciable amount of heat there.

I reckon there's calcs to show how much energy is in, say, a 55 gallon drum of coolant at x temperature. Of course, that drum would have 459 lbs of coolant in it...

actually i started this post because i was thinking about the steam engine idea but from a practical DIY perspective.

the thermos flask for hot start up idea would work with a 20litre tank. from my biodiesel days, i know that a 20litre tank should keep its heat over-night if insulated. if its positioned in the passenger footwell the escaping heat would nicely warm the car. but would the weight be an issue?

would it be practical to make a steam engine to replace the alternator using these components?

heat exchanger from ebay -boiler
drill pump from ebay -turbine
drill -alternator
your existing radiator -condenser
a solenoid valve -to do the reciprocating