Lynx Steam Engines.com

The main obstacle I have faced in getting something useful in the hands of customers has been price.   My efforts have been focused lately on providing an affordable system that is safe and affordable that will do work.  The main work customers are interested in, is converting wood, bio-mass to electricity.  While everyone wants a 2kw system, the realities of doing this are daunting.  The size and complexity of doing this is beyond the realm of a backyard system.

I have settled on a system that is reasonable in size, complexity and price.  The system is a 1hp engine linked to a monotube boiler you can make.  The generator is a small axial flux permanent magnet alternator.  One important thing to note is that tending the fire is a time consuming prospect.  You could devise a way to auto feed wood chips, but that adds complexity.

The engine I have settled on is a P.M. Research model 4C1.  It is similar to the Mike Brown engine in bore and stroke.  PM Research rates it at 1/4hp, while Mike Brown rates it at 1 hp.  Settling on this size engine stems from the size of boiler needed that most people would tolerate, and the need to keep the cost down to a $1000 range.  The engine itself will be ready to run at $925.  The boiler kit will cost around $225, and the PMA generator will cost around $200.

The main obstacle to keeping the price down anymore is the fact that none of these components are mass produced.  If they were made in China by the boatload, the price would be $300 for everything.

Below you will see some of the testing of the Typhoon Rotary engine.  For now its still too expensive to have built in quantity, so it will have to wait.  It would drive a PMA generator instead of the heavy flywheel.  To the right is some testing of the monotube boiler.

The boiler you see in the video is still too complicated for the average person.  The boiler you will make from the kit will be made from brick, copper tubing, fittings supplied in the kit.  The best way I have found to control the monotube is a simple 12v dc water control, and a automatic dump valve set at 90 psi, and an additional safety valve set at 125 psi.  Trying to control pressure with a wood fed fire is very difficult.  What I have found is that it takes a lot fire to maintain a good working pressure while the engine is doing work.  If the fire is overfed, the excess pressure is released from the auto dump valve.

To avoid the need for a high pressure pump, regular house pressure can be used with a check valve.  But, 60 psi is about the best you can maintain with house pressure.