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

[aerohead]

the hot water could power a turbo-generator as is done in Israel with solar-heated water.Refrigerant,just like in your air conditioner, is flashed to superheat with the hot water,then channeled through a multi-stage turbine,turning an electric generator.A small portion of the produced power is used to compress the gas to a pressure where it will condense back to a liquid,to repeat the cycle.----------------- If both the cooling system and exhaust heat of the engine is harvested,your looking at 2/3rds of the fuel's energy as your input energy.---------------- The electricity produced could do anything you choose.

[Frank Lee]

Originally Posted by modmonster

back to the thermos of hot coolant idea -does extra water in the system add to pumping losses? i remember it says somewhere on here to fill oil to minimum dipstick to reduce pumping losses.

No. The oil level thing is due to "windage" of oil striking and being carried around inside the crankcase from the moving parts. The water pumping situation is completely different.

I like the thermos idea. I wonder why Prius did away with it???

[NiHaoMike]

Store the heat, but run the coolant through some copper tubing in an insulated box filled with wax that melts a few tens of degrees below normal engine temperature. It will store more heat than the same volume of water as there's a phase change involved.

[Bicycle Bob]

The wax sounds like a useful refinement to reduce weight, although it can't be pumped itself.

Great minds think alike: I'd actually posted this on another list recently, not here:

The waste heat from a gallon of gas would raise the temperature of 400 kg of water from near room temperature to near boiling. That's less weight than many battery packs, and it can be pumped into the house, replacing up to 3/4 gallon of fuel oil. The tank could be filled according to the trip planned, aiming to have it almost boil.

[modmonster]

are there any negative side-effects that we are missing? if we mess around with the radiator temperature will we affect the efficiency of the engine?

[Daox]

No, the radiator is simply there to expel excess heat energy.

[modmonster]

i just calculated component power requirements for the steam engine idea. the drill pump was only good for 4 watts. we would need a mid sized radiator or shower pump to get 200 watts and that would cost about £100, so its out of my budget. it would be a full time job trying to put it all together!

deep cycle batteries are probably cheaper and easier for replacing the alternator

[hypermiler01]

Oh, I know!!! You could take the hot water, run it into the passenger compartment, and run it through a radiator there, using it to heat the passengers!!!






For short trip city driving, you are increasing the thermal inertia, making the engine take longer to warm up (even if you start from a higher point), meaning more time below efficient operating range. And yes, added weight makes a significant reduction in stop and go driving.

And for running a steam engine, you need .................. STEAM!!!!!!!

The coolant is slightly below or just barely above the boiling point, meaning not enough heat to boil water through a heat exchanger.



A much more promising method is to cover the exhaust pipe with thermoelectric cells that directly convert exhaust heat into electricity, possibly eliminating the need for the alternator.

[chuckm]

A small portion of waste heat could be used to bring the temperature of the gasoline, just prior to injection, to around 150ºF. The components will volatilize easier.

[Bicycle Bob]

"For short trip city driving, you are increasing the thermal inertia, making the engine take longer to warm up (even if you start from a higher point), meaning more time below efficient operating range. And yes, added weight makes a significant reduction in stop and go driving."

I'd leave the thermostat in the circuit, to only allow cold water into the engine side under the same terms as water from the radiator. Drawing water from an insulated full-hot tank could help return an engine to efficient operating temperature after parking without a block heater, which could be good practise year-round. (Of course, the oil pressure accumulator is even easier, and seldom implemented. It saves gas in the parts-delivery aspect of car ownership.) For stop and go traffic or hills, regenerative braking would help handle the weight.