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pmiulian · 10-21-2012, 11:56 AM

Hei - sorry for not being clear on my idea. I was thinking that the car wastes a huge amount of heat anyway.
Even if driving eco, the gas is still being burned and the heat is wasted - is all in the way the ICE works ( the 25% efficiency for gasoline ).
I know all the threads that you provided - thank you. But I see a problem with all those approaches. The insulation on the Prius engine is fine - also the thermos. But there isn't enough heat stored. The insulation capacity is limited.
The metal from the engine and the coolant will store a good amount of heat anyway, but it still isn't enough. From my point of view, the perfect car wouldn't have a radiator.
It would maybe carry with it about 100kg of wax instead.

I did mention wax ( or paraffin wax ) for a reason. This is a common and affordable PCM ( Phase Change Material ). That means that it will melt within the engine temperature operating range. When melting, the PCM stores a huge amount of heat. Wax is cheap and easy to find, almost free compared to the Prius thermos.

I tested this with about 0.3 Kg of wax, using 3 small recipients used for portable coolers. The were filled with a glycol mix I think - because of the same principle. That glycol mix would change phase when freezing / melting - so it would absorb a huge amount of heat for it's size. With the test recipients I was able to keep the engine warm for about 4-5 hours in the summer ( to about 50 deg Celsius ) and for 2-3 hours in the harsh winter ( to about 30-40 deg Celsius ). The main problem for my test was that after a while, the wax started leaking and I was afraid for the engine not to catch fire. So I need more wax and a better recipient - a metal one.

I was saying about the perfect car. With an engineered PCM and a huge amount of it, the car would never need a radiator. Or just need it for emergency. More than that. If you could store 50% from the heat generated on a 50-100 km daily commute, when arriving home, you could just plug the car in, and have instant heat for the home.

L.E.: I guess, with this kind of tuning, the car would become a mobile co-generation plant.

10-21-2012, 11:56 AM	#17 (permalink)
pmiulian EcoModding Lurker Join Date: Jun 2011 Location: Romania Posts: 23 Thanks: 0 Thanked 2 Times in 2 Posts	Hei - sorry for not being clear on my idea. I was thinking that the car wastes a huge amount of heat anyway. Even if driving eco, the gas is still being burned and the heat is wasted - is all in the way the ICE works ( the 25% efficiency for gasoline ). I know all the threads that you provided - thank you. But I see a problem with all those approaches. The insulation on the Prius engine is fine - also the thermos. But there isn't enough heat stored. The insulation capacity is limited. The metal from the engine and the coolant will store a good amount of heat anyway, but it still isn't enough. From my point of view, the perfect car wouldn't have a radiator. It would maybe carry with it about 100kg of wax instead. I did mention wax ( or paraffin wax ) for a reason. This is a common and affordable PCM ( Phase Change Material ). That means that it will melt within the engine temperature operating range. When melting, the PCM stores a huge amount of heat. Wax is cheap and easy to find, almost free compared to the Prius thermos. I tested this with about 0.3 Kg of wax, using 3 small recipients used for portable coolers. The were filled with a glycol mix I think - because of the same principle. That glycol mix would change phase when freezing / melting - so it would absorb a huge amount of heat for it's size. With the test recipients I was able to keep the engine warm for about 4-5 hours in the summer ( to about 50 deg Celsius ) and for 2-3 hours in the harsh winter ( to about 30-40 deg Celsius ). The main problem for my test was that after a while, the wax started leaking and I was afraid for the engine not to catch fire. So I need more wax and a better recipient - a metal one. I was saying about the perfect car. With an engineered PCM and a huge amount of it, the car would never need a radiator. Or just need it for emergency. More than that. If you could store 50% from the heat generated on a 50-100 km daily commute, when arriving home, you could just plug the car in, and have instant heat for the home. L.E.: I guess, with this kind of tuning, the car would become a mobile co-generation plant. Last edited by pmiulian; 10-21-2012 at 12:12 PM..