Stirling engine generator/hub motor idea

Jemma Hawtrey · #1 07-10-2008, 12:38 PM

Given we run IC engines on the bikes we are all wasting one large energy resouce... aka the heat from the exhaust.

These engines when running produce a hot exhaust which is just basically transmitted to air in the fumes and by radiant heat.

How about fitting up the muffler of an engine with a stirling heat engine running a small 12v generator (a bottle wheel dynamo for example). The power from this could be used to trickle charge a battery on the bike all the time the engine is running and/or used to provide lighting.

The battery could then be utilised to power a hub motor for short bursts, such as hill-climbing or fast running for short periods...

The advantage of this idea is that there is no drag on the drivetrain so it doesnt slow the bike.

just a thought..

Jemma xx

**Bikeguy Joe** · #2 07-10-2008, 05:57 PM

Good idea!
Stirling Engines, Waste heat recovery, Sterling Engines- American Stirling Company Home Page

Stirling engine - Wikipedia, the free encyclopedia

stude13 · #3 07-10-2008, 06:08 PM

hi jemma; i enjoy your way of looking at the possibilities of these little engines. as soon as i can i will try nitro idea, the sterling is beyond me. again you go girl. mitch

Tj Bunch · #4 07-16-2008, 12:36 PM

Jemma, Always thinking outside of the box that is so cool. I never get these cool ideas my brain is always confused with other Crap lately.

Jemma Hawtrey · #5 07-16-2008, 01:56 PM

Quote:

Originally Posted by Tj Bunch

Jemma, Always thinking outside of the box that is so cool. I never get these cool ideas my brain is always confused with other Crap lately.

Umm... I have plenty of 'crap' to distract me at the moment... being almost to the point of eviction and a terminally ill girlfriend being the two major issues at the moment.
But its true, I do have a unusual mind that seems to go off at tangents... another being using a stirling engine generator to help power offices, using the waste heat from all the servers & computers in said offices

Jemma xx

deacon · #6 07-16-2008, 03:20 PM

The only think I see that would cause me to wonder is the extra weight of the components not the generator but the battery it charges. It might be good to run a lighting system while the bike was moving but I wouldn't try to store the excess. The weight of the storage would probably cancel out any good from the generator.

Lights and horn now there's the ticket.

stude13 · #7 07-16-2008, 03:27 PM

but if you are running a hybred the battery is already there.

deacon · #8 07-16-2008, 03:39 PM

I have run ebikes they call hybred but they have no heat source. I have never run a gas and electric bike. I would think they would be terribly heavy and hard to manage though.

stude13 · #9 07-16-2008, 04:29 PM

what i meant by hybred is an e-bike with gas motor like augies idea. i would think that to be an ideal situation or close to it. mitch

badjester · #10 09-05-2008, 05:24 PM

Maybe if you wrapped a length of the exhaust with a coil that heated vegetable oil and fed into a small resevoir you could use this heated oil as the expansion side of the engine and use some fins on the air cooled vacuum side.

Then the stirling engine could keep running even when you are done riding and could then charge the batteries over a longer period of time.

Running the stirling engine on a shimano hubs an idea I've kicked around awhile. But I've only worked with beer can engines myself and have yet to make that much power, but I've seen engines that could and would probably benifit from one.

These engines get pretty big and make little power to size, but , it really aint that necessary to make huge watts when these batteries will only absorb so many watts per hour anyways. Maybe a smaller output but long lasting and "FREE" generator would be good? interesting.

Cool idea... last one I thought I'd see here but you made it apply. Rock on.