Micro Cogeneration domestic

[Capt_Maloche]

10 to 15 Kw electric, it starts to make noise

Valid for all mountain chalets !!

[the middle]

8) Here is a news about domestic microcogeneration.
It is a wood boiler equipped with a stirling engine.
https://www.econologie.com/forums/moteurs-st ... t5703.html

Retail review

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The company Sunmachine from Nuremberg has developed a 520 cm3 Stirling single cylinder under 33 bar which displays a power of 3 electric kW (measured power with a gas burner). This engine was re-equipped with a downward-down flame burner. The manufacturer announces an electrical yield of 20 at 25% and thermal up to 70%. Its price HT should be located towards 23.500 €.
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The Austrian boiler manufacturer Mawera is working on a prototype equipped with a Stirling 4 engine double action cylinders: the exhaust gases leave the combustion chamber at a temperature close to 1 300 ° C; for this, the combustion air is preheated with part of the exhaust gas. This system displays a nominal electrical power of 35 kW for a heating system return temperature of 60 ° C. The manufacturer announces an electrical efficiency between 12 and 18%. Two trial installations combine 16 000 hours of walking.
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The Stirling engine of the Austrian Stirling Power Module at 4 dual action cylinders develops an electric power of 1 kW, and its burner 15 thermal kW. This engine, developed specifically for wood fuel, will be sold as a module and can be adapted to work with the burner of different manufacturers. The first tests in real conditions should begin in 2007 in association with the Austrian manufacturer of pellet boilers KWB. The Fraunhofer ISE is working on the design of this system with a high-performance hot water tank.
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Lichtenstein's Hoval is working on the integration of a Stirling engine from 1 kWel with its pellet boilers and its wood gasifier. The company will not market it before 2008.
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the German Solo Stirling adapts its engine with a capacity of 9 kWel - a measurement performed with a natural gas burner - to work with a pellet gasifier. The engine will be heated by very hot exhaust gases. This combination will not be offered before 2007.
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German boiler manufacturer OTAG is adapting its system based on a Lion steam engine with a capacity of 0.2 to 3 kWel (with a natural gas burner of variable power from 2 to 16 kWth) to work with a pellet burner . Marketing on 2007.

I can not insert the image of the machine in the post ...

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It's good info, all that.
To insert the images, there is a post, somewhere that explains how to do it.
https://www.econologie.com/forums/comment-me ... t1176.html
A+
Alain

[sebabonnet]

For my part, I sized a micro-cogeneration system based on an Ericsson engine and producing an electric power of 11 kW. The details of this system are explained in my thesis.

The cost of this machine is substantially equivalent to other systems of the same power and would be very profitable.
Unlike systems based on the Stirling engine, this system can be controlled via the engine valves.

A prototype is in progress and we will see the results.

[Capt_Maloche]

I can not wait to get your results

See you !

[fbedon]

Very interesting the products presented in this article it looks a bit like what I want to do.

[chatelot16]

the 2eme ericson engine looks a lot like a steam engine: we compress air, we heat it to make more volume, and we give it to a motor the compressor and the engine make the same pressure: it is the largest flow in the engine that makes it provide more power than consome the compressor, if it is good enough, alas the expansion is not huge and if the compressor and engine are not super good it does not work

with steam it is simpler: we pump water, the boiler makes steam that is given to the engine: the difference in water flow and steam is huge, whatever the poor performance it always works

the stirling displacer is more economical than the air flow in the ericson, but anyway, for temperature compatible with steam it is the best steam engine: the stirling is good for higher temperature impossible for steam

[Pierre-Yves]

There is a very good study of the Ericsson cogeneration engine in Sébastien Bonnet's thesis:
http://tel.archives-ouvertes.fr/docs/00/11/01/17/PDF/These.pdf

Oops! I just saw that this reference had already been given here ...

Chatelot, I saw the good comparison you made on the Stirling and Ericsson engines and on the steam engine. With a delta T of about 200 degrees, how do these different machines behave?

[chatelot16]

the steam is not limited in delta T: the limit is the temperature of the hot spring, which gives the pressure in the boiler

P = (T / 100) power4
P in bar
T in ° C

with 200 ° we have already 16 bar and above it goes up very quickly: we approach the critical temperature and this empirical formula is no longer valid

superheated steam can be made, ie without increasing the pressure, but it brings much less efficiency than increasing the boiling temperature: most of the heat is received by the boiler not by the superheater : it only increases the efficiency of part of the cycle

the steam is also limited to the low temperature: it makes low pressure, almost vacuum, it takes huge pipes to make not much

the stirling can be easily adapted to all the temperatures: the efficiency is always further from the theoretical maximum of the carnot than the steam, but when one can take advantage of enormous temperature one can do better than the steam

when the fuel can be used in a diesel engine or diesel, steam or stirling no longer have any interest: the diesel engine or diesel engine is very easily better performance than stirlin or diesel and especially a much lower cost: look at a 2KW generator engine, and imagine the steam or stirling engine to do the same thing: it will be much heavier and therefore more expensive

even for wood: I much prefer gasogen + engine explosion boiler and steam engine

the explosion engine available can be a little weak life, but it will be possible to make or change the wear part much more easily

[Pierre-Yves]

when the fuel can be used in an explosion engine or diesel, steam or stirling no longer interest: the diesel engine or diesel have very easily better performance than stirling or diesel and especially a much lower cost price

I totally agree, as long as the energy comes in the form of a fuel. Now there is also the thermal energy of exhaust gases, autoclave vapors, industrial fumes and so on. This energy often has a low delta T, so hardly exploitable by a Stirling (except to have huge size exchangers). In most cases, this energy is lost ...

Do we know the minimum delta T for an Ericsson engine? 200 ° are they sufficient for a steam engine?

[chatelot16]

a steam engine works very well with a low delta T! the first watt steam engine was running at just 100 ° C the boiler was steaming at atmospheric pressure, it was the vacuum in the condenser that was driving force

the steam is well suited to recover power between 100 and 50 ° C

I have a project of special explosion engine cogeneration: the cooling will not be just water but steam: the engine block will serve as boiler and the steam will eventually run a steam engine: the gain in total efficiency is not Huge: 5% maximum, but it's not my only motivation: it's mostly to have 110 or 120 ° C steam almost free to distil fuel-efficient products

the huge boat engines already end the cycle with steam

to take advantage of condensation at less than 50 ° C water vapor is not very good: pressure too low almost vacuum: it takes huge diameter for not much: it is better to use refrigerant machine fluid

no freon or other cfc: simply R290: it's the refrigeration name of simple propane

Mr. DIESEL began his search for the best engine by replacing the vapor with other fluid, such as chloroform.

to cool a propane engine with propane is interesting when we have a very cold cold source kind geothermal drilling that gives water to 15 ° C: the steam engine can not exploit such a low condensing temperature

heat pumps are proof that we know how to make well-sealed thermal machines

if the steam can earn 5% of efficiency after a blast engine, propane will do better: the game is not worth the candle except for that

but if the propane machine is used as a heat pump in winters, it can be used as a recuperator on the engine in summer when the heat is useless

of course you need a heat pump really reverssible: whose compressor turns into engine: another thing to invent

there is already enough work to make a good cogeneration engine special explosion, the rest will be for later ...