Idea -would it work?

[Danncomm]

Some time ago I was reading an article about BMW planning to remove alternators from future cars and replace them with thermocouples mounted to the catalytic converter recovering about 800w. from the heat. I was just wondering if something like that could be done using the whole exhaust system and engine block on my Honda Insight and feed the resulting electricity to the IMA so the engines excess heat would actually have the IMA help push it down the road and therefore gain some extra mileage?
If this will work, what kind of mods would need to be done to the IMA's controller?
What kind of mods would need to be done to the charging program?
Maybe we can get something going here to do something really neat with thermocouples.


This would make alternator deletes easy, pull the belt and run the thermocouples in series to get to the 13.8v with enough amps to cover usage and feed it threw the alternators voltage control so as not to over charge the battery of a regular auto.

So all you mad scientist types put your thinking caps on and maybe we can do something great here or maybe I am way off base here.

[RobertSmalls]

Hey, cool, another Honda Insight owner thinking about thermoelectric waste heat recovery. I hope that's a first-gen Honda Insight. Lean burn's higher EGT's and the smaller scale of everything on the Insight make it a good platform for thermoelectrics. However, displacing usage of the Insight's ~85% efficient "alternator" saves less gas than on a car with a 50% efficient charging system.

But yes, thermoelectrics should save fuel, albiet not much.

Originally Posted by BSST

In 2004 (Phase 1), the team created a system architecture and established subsystem designs that were modeled in a bumper-to-bumper performance simulation that showed up to 12% fuel economy improvement.

Key words there are "simulation" and "up to" 12% improvement.

Technical Papers - BSST Thermoelectric Temperature Control Solutions

But it would be immensely expensive for a small trickle of electricity. If you have a few grand kicking around and you want to buy a couple MPG, this could be a mod worth developing.

Actually, I have no idea how much the TE modules cost, but you (or I) could write to Dr. Bell and find out.

Welcome to the forum, and please tell us about your car.

[Ryland]

last I checked thermo electric generators were around $8 per watt and you need... 100-200 watts just to power the ECU, lights, spark coils.

[busypaws]

Next exhaust mod:
Put large surface area mulfler in place of current muffler and 13 gallon gas tank (New 5 gallon gas tank in trunk spare wheel well). Bond Thermoelectric generators over entire surface of 20 gallon switchback muffler. Get 5amps when fully heated and remove alternator. --- Save 1-2mpg but cost 800+ dollars.

Just guessing at the numbers --- but thermoelectric will not replace an alternator.

[Danncomm]

I just bought the 2006 Insight last fall after someone played smear the deer with it. I have put about $3000 worth of repairs into it and should have it back from the body shop where they are doing the few things I couldn't on the frame work. The only experience I have had with driving it was from my house to the body shop about 6 miles away and watching the mileage meter go from 60.2 mpg to 60.3 mpg for an average reading over the last 1600 miles. I cant wait to get it on the road and see what I can do with it for mileage.
Guess I will have to wait and see what else they come up with in thermo electrics, I read a story a day ago that they found that they could put the plates closer together than they thought they could and they would produce more electricity than before. Maybe sometime soon they will improve things enough to make it worthwhile to do. Until then I will keep reading and thinking.