Recovering waste heat from natural gas generators

[basil___1279]

Hi,
Denmark calling

I need information to set this project in motion: I have an 40 kW electric generator set up for making 3 phase 380V/50hz for home use and for selling
through the powergrid. The heat from the engines cooling system is soon to be connected to the house central heating, taking care of some of the waste
heat.
Now i am looking into ways of turning as much of the exhaust heat into electricity as possible. I believe that a Stirling engine would be the answer, but
have been quite unable to find units of a size that will fit my needs.
Are there such engines available at all?
And, perhaps i should ask this too: Am i on the right track at all?

Regards
Henrik

[info74]

You clearly are on the right track to use the heat from the engines cooling system to supplement house central heating. That much is simple cheap and easy.

What you would also like to do is use the perhaps 1000 deg F. (537 deg. C) exhaust to power a Stirling engine and make more power to use yourself or sell to the grid. To the best of my knowledge no one has such a Stirling engine out there. It is one of the best target markets for Stiriling engines and unfortunatley our company doesn't have the development money to dive into such a large project.

Perhaps you might be willing to help future investors or developers of an engine like this by posting how much you would be willing to pay for it and what you would want it to do. Please realize that any new product like this would initially be sold in relatively low volume and as such would cost much more per kW than a comparable IC engine. [But the fuel would be free!]

[basil___1279]

Hi again,
Thank you for the answer.

OK, then. If an engine unit like i need is not available... I'll build it myself. This not as sudden a decision as it might seem, as i have been fascinated by the Stirling engine since the seventies when ford build the Stirling automobile engine.

Now, what i need is information to get me started on sketching an engine. Information like machine part loading, capacities and old designs to steal ideas from, heat exchangers. and what have you.

What textbooks are there? Which of these are the "must haves" and which the "nice to haves"

Through my work i have access to the tool machines needed, i have a boss who will let me use them. Not the least i have collegues who will help me get over the the hurdles of the trickier machining. I realize i am bragging, but i do not really think i am being unrealistic, just ambitious

Regards
Henrik

[info74]

First you should have no illusions that you will save money or that this will be easy. It will be both expensive and difficult. Of course if you succeed you will feel incredibly proud of yourself and even if you don't the learning experience may be worthwhile.

First I'd recommend that you read, "Making
Stirling Engines by Andy Ross. Mr. Ross spent a huge time and effort trying to build a fractional hp Stirling engine. Second, build your engine thermodynamically similar to one that is known to work and put out power in the range you are targeting. Several R&D engines like this do exist, but finding one and finding someone who will help you will be no-nonsense hard.

Conserve your energy. Once you have a design that you know will work stick with it until you have it perfected. Andy Ross recommends this and I highly agree. Don't switch from one design to another.

[barry.cullen]

Hello,
I am a new enthusiast and have just registered on this site. I am fascinated by this concept.

From what i can understand Stirling Engines are extremely difficult to realise in power producing mode and typically are done on huge budgets, have you made any progress on this?

[jagjitsinghchander]

Hi

I have joined the forum today and have same question in my mind

but about the diesel generator which use for 24 hrs in a day and my

monthly running cost is approx 3800 USD. i would like to be the part

of your project any way