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theunchosen · 11-24-2008, 01:26 AM

So I am new to the eco-modding forums, and I have a pitch.

Essentially The largest problem with ICE is that 60% of your converted power leaves the engine unused. Actually, this is the problem with all engines, you lose power somewhere you don't mean to. Unfortunately there is no beautiful mechanical method to scavenge this heat energy that goes out the tailpipe and off the engine block, otherwise we would probably have it OEM.

This is where the hybrids come in. Hybrids are more efficient because they are capable of reclaiming energy in places that ICE cannot. For instance there is virtually no way to reclaim power out of braking in an ICE, but hybrids can do it just fine. Ultimately hybrids are more efficient because they are designed with less aggressive engines and fuel maps to conserve fuel rather ego. Also mechanisms for turbocompounding are not very effective because of complicated gearing that must go into connecting a turbine from the exhaust to the drive shaft.

A possible solution exists, not that its good or feasible, but its there. An old engine given a new chassis and guts has become the hottest new toy in commercial energy production, The Stirling. Stirling Energy Systems(SES <http://www.stirlingenergy.com/>) has manufactured a stirling engine that comes close to its ideal max. You can look at their system but in the short they take 700 degrees from focused sunlight and produce electricity through the stirling engine.

Its just under the size for a 400cc engine to produce their "25 KW"(33 horsepower), which is impressive considering my 1.5 outputs a weak 101 in comparison(good for fuel economy but weak because equivalently sized stirlings could crank 130 hps). Like a true carnot engine the stirling takes a long time to spool up and respond to temperature change(unlike your gas pedal) so its out to juse burn gas and let the stirling take over.

To the proposal.

Rip out the trans(saving some energy from mechanical losses and heat), route the engine shaft into a generator(losing some energy to conversion(heat, magnetic fields, blah, blah) powering your car with two electric motors half the horsepower of your original(smaller engines attached directly to the wheel evade drive shafts and their associated weights and energy losses(or four engines 1/4 original horsepower)). Attach Stirling engines downstream along the exhaust pipe(not the same size as the 4x95cc SES, probably smaller and 3-4 of them) and after the initial spool up of the stirlings you recover nearly 60% of the energy your burned gasoline gives off instead of sub 30% in standard ICE. A problem yet unsolved by mechanical means is how to reclaim or prevent losses while at idle. Unless the engine is cut off it is wasting enormous amounts of energy(virtually all of it, excluding any energy converted for headlights or brakes). Also it avoids the expensive and heavy hybrid batteries. Instead of 500 lbs of batteries just add one or two to the trunk to reclaim solar, braking and idling electricity.

Obvious downsides
removed parts will not outweigh stirlings, generator assembly and batteries.
Minimal if any economy gain for the initial spool up time
Probably more that I've thought of but its late and I'm tired(I'm sure there are plenty I haven't thought of and will soon hear).

Bonuses
Could drop engine size for improved fuel economy because the stirlings would boost HP after they warmed up on the hotside(however long it takes your car's exhaust pipe to burn you)
Could recover electricity from regenerative braking and solar if your car is parked during the day.
Could remove components of the car that are heavy, expensive and break.
Instead of having complicated CV joints for FWD could use less complex more reliable(comfortable) joints since the power could be generated on the other side of the joint.
All ICE improvements to efficiency are added bonuses i.e. HCCI, turbocharging, lean burn
Does not involve an enormous increase in weight for hybrid batteries,fuel cells or "weighty" objects
Could jump overall car efficiency from 30% to 60%.

11-24-2008, 01:26 AM	#1 (permalink)
theunchosen Master EcoModder Join Date: Nov 2008 Location: Cookeville, TN Posts: 850 Thanks: 1 Thanked 5 Times in 5 Posts	Newbie pitch So I am new to the eco-modding forums, and I have a pitch. Essentially The largest problem with ICE is that 60% of your converted power leaves the engine unused. Actually, this is the problem with all engines, you lose power somewhere you don't mean to. Unfortunately there is no beautiful mechanical method to scavenge this heat energy that goes out the tailpipe and off the engine block, otherwise we would probably have it OEM. This is where the hybrids come in. Hybrids are more efficient because they are capable of reclaiming energy in places that ICE cannot. For instance there is virtually no way to reclaim power out of braking in an ICE, but hybrids can do it just fine. Ultimately hybrids are more efficient because they are designed with less aggressive engines and fuel maps to conserve fuel rather ego. Also mechanisms for turbocompounding are not very effective because of complicated gearing that must go into connecting a turbine from the exhaust to the drive shaft. A possible solution exists, not that its good or feasible, but its there. An old engine given a new chassis and guts has become the hottest new toy in commercial energy production, The Stirling. Stirling Energy Systems(SES <http://www.stirlingenergy.com/>) has manufactured a stirling engine that comes close to its ideal max. You can look at their system but in the short they take 700 degrees from focused sunlight and produce electricity through the stirling engine. Its just under the size for a 400cc engine to produce their "25 KW"(33 horsepower), which is impressive considering my 1.5 outputs a weak 101 in comparison(good for fuel economy but weak because equivalently sized stirlings could crank 130 hps). Like a true carnot engine the stirling takes a long time to spool up and respond to temperature change(unlike your gas pedal) so its out to juse burn gas and let the stirling take over. To the proposal. Rip out the trans(saving some energy from mechanical losses and heat), route the engine shaft into a generator(losing some energy to conversion(heat, magnetic fields, blah, blah) powering your car with two electric motors half the horsepower of your original(smaller engines attached directly to the wheel evade drive shafts and their associated weights and energy losses(or four engines 1/4 original horsepower)). Attach Stirling engines downstream along the exhaust pipe(not the same size as the 4x95cc SES, probably smaller and 3-4 of them) and after the initial spool up of the stirlings you recover nearly 60% of the energy your burned gasoline gives off instead of sub 30% in standard ICE. A problem yet unsolved by mechanical means is how to reclaim or prevent losses while at idle. Unless the engine is cut off it is wasting enormous amounts of energy(virtually all of it, excluding any energy converted for headlights or brakes). Also it avoids the expensive and heavy hybrid batteries. Instead of 500 lbs of batteries just add one or two to the trunk to reclaim solar, braking and idling electricity. Obvious downsides removed parts will not outweigh stirlings, generator assembly and batteries. Minimal if any economy gain for the initial spool up time Probably more that I've thought of but its late and I'm tired(I'm sure there are plenty I haven't thought of and will soon hear). Bonuses Could drop engine size for improved fuel economy because the stirlings would boost HP after they warmed up on the hotside(however long it takes your car's exhaust pipe to burn you) Could recover electricity from regenerative braking and solar if your car is parked during the day. Could remove components of the car that are heavy, expensive and break. Instead of having complicated CV joints for FWD could use less complex more reliable(comfortable) joints since the power could be generated on the other side of the joint. All ICE improvements to efficiency are added bonuses i.e. HCCI, turbocharging, lean burn Does not involve an enormous increase in weight for hybrid batteries,fuel cells or "weighty" objects Could jump overall car efficiency from 30% to 60%.