electrical power from heat using refrigerant

[petect]

Hi to all.

I stumbled across Tomwol’s post “compressor for wind powered heat pump”, and found it to be very interesting. I too am not refrigeration professional, but hope that some of you will take the time to share your expertise.
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Here’s my situation: I want to use heat stored in a thermal mass ( outdoor wood furnace – possibly some solar ) to expand a refrigerant which will be converted into mechanical energy by means of a turbine or expander to drive an alternator and generate electricity.
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Based on the availability and cost of materials I’m looking at the following, and have added my thoughts about them:>
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Automotive turbocharger – lubrication, leakage, lack of torque at lower rpm’s ?>>
Automotive air conditioner scroll compressor ( from a big car) run backwards as an expander – may be able to use its clutch to engage / disengage & can use multiple expanders as needed, lubrication ?>>
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Ammonia – cheap, potentially dangerous, corrosive>
R134 – expensive>
Butane or propane – less expensive, potentially dangerous>
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Heat source – storage mass from wood furnace: 55 – 100+ deg C>
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Condensing (possibly ambient air in winter) >
Probably water from a shallow well: 10 – 18 deg C >>
Output – hopefully 3000 – 4000 KVA >
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I hope that by making a fairly compact system I can keep refrigerant safety considerations and costs to a minimum. The cooling water may need to be pumped to the condenser. >
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I’m sorry for being so vague. At this point I’m hoping to get some advice, and constructive criticism to point me in the right direction. At some point I will need to buy some (hopefully) good used components, and start testing. >
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Thank you in advance for any assistance.>
Pete>
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[taz24]

Hi to all.

Hello.

If I was you I would do a search on Stirling Engines.
They will give you the solution to your problem.


Cheers taz.

[taz24]

Hi to all.

Try


http://www.stirlingengine.com/ecomme...&product_id=84


taz

[petect]

taz

Thanks for the suggestion. I will revisit using a Stirling.
I'm hoping to use as many off the shelf components as possible.

Do you think a scroll expander with R134 could work>

Pete

[Tesla]

Ive seen a video of this system I bought from nexus magazine called free energy devices (or something - race to zero point). It used an old opendrive recip compressor. There are many other devices out there, check out hutchison (john), geet fuel processor, water fuel. The one above was a big machine which produced small power for free.

[taz24]

taz

Thanks for the suggestion. I will revisit using a Stirling.
I'm hoping to use as many off the shelf components as possible.

Do you think a scroll expander with R134 could work>

Pete

Hi Pete.

I'm not sure that a scroll would work.

But I have heard them forced to run backwards when the check valve has failed in the discharge of the comp.
When the comp shuts down the high pressure gas from other running systems does reverse the scroll.

The problems I could see is oil lubrication and bearing stress. The bearings are designed for the load to be in the other direction.

Cheers taz.

[US Iceman]

Somewhere I remember reading about a scroll expander. Have no idea where I saw that, but I suggest you keep searching.

What is a compressor could also be used as an expander with the correct modifications for the reverse flow.