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4.5 kW Biomass fueled engine

PostPosted: Thu Sep 26, 2002 9:56 pm
by info74
People often call me asking where they can get a 5 kW or so Stirling
engine that will burn their favorite fuel. I recently had the
opportunity to read, "Principles and Applications of Stirling Engines"
by Colin West and on page 206 it tells about a 4.5 kW rice husk
burning Stirling engine that was financed by the US Agency for
International Development and built by Sunpower of Athens Ohio.

The book is available from Stirling Machine World.

I'm taking the liberty to be re-post a 1998 letter by L. Merrick
Lockwood that I found here:

The e-mail address that I have for Mr. Lockwood bounces. If anyone
knows how I can get in touch with him please contact me at the phone
number on our contact us page.


From: Merrick Lockwood
House 43, Road 23, Banani
Dhaka, Bangladesh

Dear Tom and Ronal,

I have been tuned in on the stoves list for quite some time and I
guess I should be contributing my two cents worth. Tom's
upcoming trip has prodded me to do this now in the hope that this
reaches him before he leaves for India and the Philippines.

I have been involved with Stirling engines since 1979 when I
proposed a project to The Asia Foundation in Bangladesh to
develop a small (5hp) rice husk fueled Stirling engine for use in
rural rice mills. Ultimately this project was funded by the
United States Agency for International Development (USAID) and
ran from 1981 to 1986 as the Rice Husk Energy Project (RHEP). The
design of the Stirling engine was sub-contracted by the Asia
Foundation to Sunpower, Inc. in Athens, Ohio. The engine was
completed in the first year of the project and by 1982 a
prototype rice husk fueled Stirling engine had been designed,
built and demonstrated at Sunpower's facility in Ohio. The
engine had a bore of 300 mm, displacement of 7 liters and was
designed to operate at 5 bar air pressure at 600 rpm.

During the next 4 years here in Bangladesh we went through three
iterations of design modification and fabrication in a facility
we had set up near Dhaka. In this process many snags in the
prototype design were worked out but we continued to have
problems with lack of durability in the Ericsson linkage which
incorporated a bell crank system to drive the displacer. This
mechanism (excluding the crankshaft) had 8 moving parts and 12
bearings. For our last engine which was designed and made in a
crash program during the last 3 months of the project, we re-
designed the engine, switching to a massively built but simple
Ross linkage with only 4 moving parts and 5 bearings. This
engine ran quietly and promised good durability but.... falling
world oil prices and vanishing interest in alternative energy
within the US Govt. scheme of things, scratched funding for
further work.

HOWEVER, the original RHEP Stirling engine design with Ericsson
linkage survived. By 1984 two of Sunpower's people had set up
their own company (Stirling Technology, Inc.) and went into
business with an an Indian company in Madras (Stirling Dynamics)
to manufacture a improved version of the original RHEP prototype.
By incorporating the engine's compressor with the displacer rod
to double as a bounce chamber they hoped to relieve the stresses
that had been fatal for the bellcrank displacer drive mechanism
in the prototype. Their engine, the ST-5, was manufactured for a
period in Madras and generated a lot of interest in India and
abroad. I think about one or two hundred were manufactured. Of
these around 40 were procured by the Indian Government's
Department (now Ministry) of Non-conventional Energy Sources and
put in different locations in India for field testing. The
compressor "fix" worked initially, but when the compressor itself
wore out the linkage again took the load and eventually the
likleyhood of mechanical failure increased. This and other
problems, including increasing costs, eventually put the engine
into mothballs, though some are still being nursed along by a few
dedicated individuals.

Since 1986 I have continued working, part time or full time, on
Biomass fueled Stirling engines. As a matter of convenience I
have aimed at running them on charcoal, thus my interest in the
stoves list. My target engine sizes keep getting smaller, first
to 500-1,000 watts, now the latest is aimed at 100-200 watts for
electricity at the rural household level, perhaps in conjunction
with a cookstove. More on this another time.

The question for Tom is, are you going to be visiting Bangalore?
I suspect you might as Dr. H.S. Mukunda with his combustion and
gasification team at the Indian Institue of Science have done a
lot of work on gasifiers for conversion of biomass to mechanical
power in association with ASTRA. Though maybe you are focusing
on some of the commercial groups who are manufacturing and
selling gasifiers in other parts of India. In a week or so I'm
headed to south India for a few weeks and will be visiting
Bangalore which is not far from where I stay when there. If you
are going to be in that area it would be interesting to meet,
time permitting. Any possibility?

With best regards,

Merrick Lockwood

I have contacted Merrick Lockwood

PostPosted: Thu Dec 05, 2002 10:47 pm
by info74
I have recently contacted Merrick Lockwood. Read the "Team Comments" thread for some of his comments on our revival of his engine project.

Response to 4.5 kW Biomass fueled engine

PostPosted: Sun Jul 24, 2005 9:15 am
by aikane4u
As a person interested in alternative means of power,I have been keen on the progress of the Stirling engine for some time.
In 1993 here in Florida, we had Hurricane Andrew which left hundreds of thousands of tons of bio mass in the way of uprooted trees and wooden homes. I was extremely frustrated that this was not turned into energy, but merely mulched,burned or disposed of.
I started researching methods of making charcoal when I stumbled upon a new process of producing charcoal called "flash carbonization, developed by Dr. Michael Antal at the University of Hawaii. Through the use of heat and pressure, He is able to produce charcoal from biomass, even wet grass and fresh cut trees, and it can be done in minutes rather than hours and days. His prototype constructed on the campus of the U.H. cost less than 100,000. to build and will produce more than its cost in assets the first year running one 8 hour period per week. Absolutely amazing!
If You have not already discovered flash carbonization, then I think You will be delighted as to the connection toward fueling a biomass/charcoal fired Stirling generator.
Sincerely, Ken Beggs

Response to 4.5 kW Biomass fueled engine

PostPosted: Thu Jun 01, 2006 10:48 pm
by pk
it is a tragedy that the carbon cycle in nature enabled a massive increase in the forest growths in the amazon basin .. fuelled by (some researchers found) the CO2 growth in north america

yet, the use of the natural fuel .. wood .. trees .. leaves .. grass .. doesn't seem to be 'right' .. and the post-hurricane wood is treated as a 'problem' to be burned away instead of being used as a fuel


when dr. lockwood comments on the ST-5 .. and has contacted Tom and Ron .. it is a pity that his hard work has not been widely circulated nor broadcast by specialist groups working on stirlings .. and we are left with a 'book' written ..

ah well, at least there WILL remain a 'record' of this real world genius who actually 'delivered' a solution .. which worked .. till oil prices FELL .. and may work better now .. now that oir prices have JUMPED to absurd levels !


Response to 4.5 kW Biomass fueled engine

PostPosted: Tue May 22, 2007 9:05 am
by bembalkarvijay
it is very interesting to be with Stirling community i enjoid the above disscssion.i am interested in knowing about all activities going on in India about Stirling engines. regards

Response to 4.5 kW Biomass fueled engine

PostPosted: Wed Jun 11, 2008 5:03 pm
by aikane4u
Back in 2005, I was quite excited about the possibility of "flash Carbonization", a process used to efficiently create charcoal from any bio source, even sopping wet biomass. Im happy to say that visiting the site again after a few years has rekindled my excitement. So many of the initial problems have been sorted out and more efficient processes and eco friendlier production has arrived. I still see the Stirling engine and this medium creating a happy marriage.
The latest for me is the ordering of a hydrogen generator for my car. The claims of efficiency vary from person to person of these new units usually made in a small shop or garage. The claims are from 20 to 70% better fuel mileage and are simple to make. Again, like the Stirling engine, an old design brought back to life by better metals and the staggering cost of fuel. Through electrolysis, hydrogen and oxygen are separated from water into gas through some fairly low voltage and low amperage,Obviously resulting in some real volatile fuel. After fooling the oxygen sensors to the computor, you can get your car to run smoothly while substantially increasing fuel mileage and lowering pollution.
The beauty of the Stirling engine is the ability to utilize anyheat source you can throw at it. If hydrogen and oxygen can be separated so easily from water, wouldnt this be the greenest form of producing power available? Especially since the by product of the hydrogen generator is water.
If I appear to be scientifacally naive, it s only because its true. I am born and raised in Hawaii with a high school education and no scientific training. I cannot intellectually defend myself, so if I have mistakenly described this proccess, I apologize. I find this a very exciting time for alternative energy development, probably the only positive coming out of the staggering price of fuel.
As I am looking to contribute, but also to receive feedback, I would like to hear what everyone thinks about the possibilty of some simple hybrid generating systems.
It seems as though a solar cell could charge a battery which is used to supply the energy to create the hydrogen/oxygen gas used to power a quiet Stirling generator. Sounds a bit simplistic and I know it really isnt, but its very green with o pollution. The beauty is the Stirling can also utize flash carbonization made charcoal for its heat, or a wind generator to supply power to make heat from hydrogen. Either way youve got sun, wind and water and bio fuel supplying your Stirling generator.
I would just like to say, and as a disabled veteran I can say whatever I want, That now as in the past, our government has not stepped up to the plate. The protection and subsidizing of these powerful companies with antiquated and terribly polluting practices that continue to make us fossil fuel dependant,has nothing to do with what made this country great. I believe that through the lightning fast internet, technology sharing will put an end to these people who have highjacked our country and damaged our earth. The mom and pop inventors and conscientious small time manufacturers of eco friendly energy will someday succeed. ken beggs

Response to 4.5 kW Biomass fueled engine

PostPosted: Wed Jun 11, 2008 10:14 pm
by bptdude___2569

Kenneth, This thread was really focused on the ST-5 specific Stirling, but all is cool. A perfected ST-5, should one ever become available to purchase in hight quality with modern materials, could be used for many things.

For all the well proven concepts and numbers, for whatever reasons, nobody is actually producing Stirling engines in the range between demonstration models and very expensive large industrial special use.

The few medium size concepts and a couple of nice products are meant for recovering small amounts from other processes, not primary energy production.

Hydrogen production really is the answer you think it is, and you are way ahead of most of the world in realizing this. It makes for very simple engines to use it, but we are distracted by fuel cells. Any and all other energy sources, such as oil, gas, coal, and nuclear, could produce hydrogen, proviing a common energy base for consumers. It would also create a level playing field for other sources.

Long term clean solutions will be based on recovery energy from nature in forms of solar, wind, bio, and geothermal. All of these can be turned into hydrogen too. Both the Stirling engine and modern steam engines may play a major role in making use of such. Not only can you not find a medium size practical Stirling, try to find a medium size practical steam engine. Very strange, indeed.

From Hawaii? The "Big Island" has a constant flow of molten rock that dumps into the ocean. There are exeperimental geothermal plants workikng low scale. The amount of energy available could supply not only all of Hawaii, but make Hawaii a major exporter of liquid chilled hydrogen, filling tanker ships to very happy customers.

So, if you can ever get hold of an ST-5, play with it to use hot lava on the hot side and cold ocean on the other, to make your hydrogen. Maybe you will get rich! *smiles*

Response to 4.5 kW Biomass fueled engine

PostPosted: Tue Oct 14, 2008 2:21 pm
by esteamed_colleague
aloha ken, i'm still living on b.i., hawai'i....the hydrogen harvested from water by one's car's electricity is a direct function of the amount of current put thru the actually drags down performance and adds to the bank account of the scammers who sell the garage made units.

Response to 4.5 kW Biomass fueled engine

PostPosted: Mon Nov 24, 2008 8:13 am
by mason1
well if any one knows were a st-5 or similer engine could be found running or not please e-mail me

Response to 4.5 kW Biomass fueled engine

PostPosted: Wed Feb 18, 2009 6:46 am
by ontuyalex
Hydroxide boosters for cars works. Using resonant Electrical frequencies to split water into Hydrogen and Oxygen and then burning it in a car WILL increase mileage. I'm currently working on a design that will run completely on water, and it HAS been done before. I don't work for any of those hundreds of companies that are producing these for profit, i'm just an experimenter, so why lie? I understand the skepticism though. If you split Water into HHO with electricity, then turned it back to electricity, it would be the same amount of electricity, except a little less because of innefficiencies. Alternatively, splitting it then burning it creates enough pressure to turn a piston and that's what matters to me.


If i wanted to create a Stirling engine to run the power my house uses, or most of big does it need to be? How do you figure that out? I'm kinda stumbling around in the dark with it.
Currently i'm working on a few solar engines to run my AC and Heat (using a solar heater and fans to take advantage of convection to both heat and cool my house), which is all fine and good, but i want More. I want to look at my roof and see my motor running and unplug from the grid. It would be nice.