James appears to be seeking a conversion experience :-)
Ridicule something for too long and you run the severe risk of 
becoming its acolyte for life.

> Try and purchase one.

Evidently you haven't followed any of the Stirling Engine links I have 
provided recently and on past occasions.
Google on Whispergen and examine some of the 22,000 hits and decide if 
it is indeed a real product or a phantasm.

Look at    www.whispergen.com
While this may look like any number of shonky sites that do not have 
real product to back up the pictures, in this case it is not the case.
Google on Whispergen and you will find they have been around for some 
years and are available for money. I have seen one in the flesh. As I 
discussed recently, they are expensive compared to IC units of similar 
capabilities and for good reason. But the reasons are not principally 
related to the cost of production.

The Whispergen was developed from scratch by a Stirling engine 
enthusiast who acquired a number of prior devices, including Philips 
Stirling Engines made in the 1950's, did his PhD on Stirling engines, 
and then developed his own patented coupling for a 4 piston unit and 
THEN commercialised it. He is Dr Donald Klucas. The parent company is 
based in Christchurch New Zealand. It is owned mainly by two of NZ's 
electricity/energy supply companies as they provided the startup funds 
and/or bought the shares of those who did. They have a contract to 
supply a goodish number (10,000? 30,000? to a UK energy supply company 
to act as load distribution units by installing them as CHP units in 
homes. Selling gas and electricity makes this attractive to a 
supplier. Whether this order comes to fruition remainds to be seen.

> What is the mean time between failure?

See above site.
Good.
Doesn't use exotica as high volumetric energy density is not required.
Has a standard maintenance arrangement, as do all engine sused in 
serious applications.

BUT - this will be of interest
http://www.mech.canterbury.ac.nz/MEFinalYear/Projects%202004/LubricationSealingSolutionsForWhisperGen.shtml
Note, you have to havea real product before you can improve it.


> Sterlings are a pipe dream.

Sterlings may well be.
But Stirlings aren't ;-)

Google on "dean kamen" and "stirling engine".
If you don't know who DK is Google him up and then the above.
DK does indeed dream some major dreams - but many of them end up 
clothed in steel and plastic and electronics.

A Sterling engine is a metal expansion engine that uses metal rods 
heated and cooled to provide motive power. Stroke is understandably 
small:-)

There have been many small Stirling engines made and a few large ones. 
The major barrier to the widespread introduction of Stirling engines 
is greed and stupidity - ie cheap petroleum and tolerance of the vast 
waste of resources. As long as people would rather waste resources at 
artificially low prices rather than acheive energy efficiency we will 
continue as we have in the past. A useful albeit incomplete analogy is 
someone with a bedroom stacked full of 100 dollar bills. As long as 
they last it's easy and "cheap" to shovel them into the fire to heat 
the house. That other people may put them to other uses and find other 
ways of heating the house does not enter the equation. Our children's 
children's children, should they get to exist, would curse us chapter 
and verse over our wastrel ways were it not for the pletious supply of 
lunar He3 that they will have to fuel their fusion reactors :-).

> Solar steam or hot air turbine engines are at least accessable NOW.

Nothing is accessible now unless you do it.
Just as vanishingly few amateurs produce significant sized IC engines 
you find few people building larger serious Stirlings.
How many amateurs do you know who have built their own eg 12 HP twin 
cylinder engine starting from scratch, apart from Orville and Wilbur?

Compared with making your own IC engine a say 1 HP Stirling should be 
reasonably easy. Using air at about 150 psi you'd need about a 250cc 
swept piston area. Large if you think in IC terms. Not at all large if 
you think in bits of metal terms. More could be said, but if the above 
does not dissuade people from making unsupported comments like "try 
and purchase one" then no amount of technical comment will help :-(

A 5 litre stainless steel soup pot run at about 15 psi should make 
about 3 horsepower when sorted :-).


        RM










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