Green Steam Engine

Licenses technology






Limited Edition

Three cylinder 10 HP engine  



Robert Green's TED talk on replacing the power grid.





Here are a few reasons to consider steam engines as an alternative to

wind and solar systems. Power ranges go from fractional HP to hundreds of HP


Steam engines can run 24 hours a day regardless of location, weather or daylight.


There are no construction costs, towers, roof panels or permits required.


There is no noise or environmental impact associated with steam power.


The Green Steam Engine may be powered by the widest range of alternative fuels, including solar and geothermal.


No back-up power required as it is for wind and solar systems.


When operated on solar, excess energy may be stored in compressed air which can be returned to the steam engine later for electrical generation. Compressed air is much cheaper than batteries.

Intermittent energy is not a solution for intermittent energy. Steam engines are energy on demand.

 For inquiries email:rgreen999@comline.com

Plans for this 2 cylinder DIY engine are available for purchase below.



Here are some examples below of different engines:

Three Cylinder Steam Engine


  Three Cylinder Direct Drive Generator

What kind of generator is used on steam engines?

Unlike internal combustion engines that need high rpm's to develop full power, steam engines have full power at starting speed. Windmill generators operate at low rpm's (100 to 600 rpm's). Although steam engines can run at high speeds, to do so requires more steam volume than necessary. It is much more economical to run them slowly. For electrical generation, use the same electrical system as you would for windmills.



Four Cylinder 15 HP Engine 



Direct Drive Generator and Compete System

Complete systems includes boiler, steam recycling (closed loop), hot water, water distiller, remote space heating and electrical generation.


Generator by: www.windbluepower.com

Z Drive Two Cylinder



Flex Rod Two Cylinder

Click on the video below to see five different engines in action

View video below for solar steam system


Six Cylinder


Z8 Engine 

See Licenses  page for video

Power a boat, a generator, air pump, water pump, heating blower, water distiller, heat pump, air conditioner, model airplanes, boats and trains or a variety of appliances with any fuel that will heat water including solar and geothermal. Waste heat from engines or manufacturing processes may also be used to generate steam to power this engine. Because it is so lightweight and compact, it could be used in vehicles to run pumps on waste heat; saving power and fuel. This powerful, quiet engine is a breakthrough in alternative energy use. Because of a revolutionary new patented means of converting reciprocating movement into rotary movement, the 

"Green Steam Engine"  has dramatically simplified the piston engine.


Plans for building a two cylinder steam engine like the one below are available for purchase.


Slow motion animation to show how it works. for a video demo, click the link below:

(note: pump in front of flywheel to recycle condensed exhaust steam)

Typically, the exhaust steam is condensed and pumped back into the boiler to increase efficiency. A small pump on the engine pumps the condensed water into the boiler for a closed loop system. 

Do-It-Yourself Plans for

this 2 Cylinder Engine are Available below. 

The DIY engine in the plans is a 2 cylinder, 10 HP version made with mostly off-shelf parts

  Boiler plans for the above boiler are also available.

The boiler plans are for a safe water-tube boiler that may be used with a variety of fuels such as gas, wood, pellets, or other bio-fuels. The boiler in the plans is easy to construct with readily available materials. The plans include the boiler feed pump that recycles the water for efficient and economical operation. The boiler may be scaled for large or small engines.

Purchase Engine Plans Now for $45.00 and Boiler Plans for $35.00.


DIY Engine Plans E-mail

Boiler Plans E-mail




Robert Green's TED talk on replacing the power grid.



See other examples of engines below

Steam engines provide advantages such as: less pollution, quiet running, high torque at low speeds, no transmission requirements, runs on a choice of fuels (many renewable), has long life with low maintenance. 

Adding to this list of special advantages, the "Green Steam Engine

" offers these unique features:  
bullet Runs on very low steam pressure and low volume (freewheels at 2 psi), 
bullet Costs little to build, 
bullet Nearly zero lubrication requirements, 
bullet Can be assembled or disassembled in minutes, 
bullet Extremely lightweight, 
bullet Few moving parts, 
bullet Boiler requirements are minimal, 
bullet Can run in any position like an electric motor.
bullet Very small profile for economy of space. 
bullet May be variably configured for desired power vs speed requirements.
bullet Utilizes modern materials and methods previously not applied to steam power.
bullet Highly versatile and elegantly simple.

The properties of the patented crank mechanism (called a "flexible rod transmission") invented by Robert Green, provides this engine with the advantage of eliminating the typical crankshaft and cam that requires lubrication and precision machining. It also provides the unique configuration whereby the cylinders are aligned in the same direction as the main shaft. The result is a  compact, lightweight and slim engine that is extremely simple to construct and assemble.

    The pistons and valves operate off a short piece of flexible shaft. Because the flexible shaft is fixed and cannot rotate, the piston rods and valve push rod are held in position while being reciprocated. The cylinders float, attached to a swivel ball fitting at their base.  Much of the structure and weight of a typical steam engine has been eliminated.

    The unique feature of the "Flex Rod Transmission" is that it produces an intermittent movement whereby the valve movement is stopped in its open and closed position during the power and exhaust strokes. This gives prolonged, fully opened valve timing. In compliment, the pistons are held stationary while the valve moves between phases. The output shaft continues rotation while the pistons stand still. The result is that the efficiency is increased dramatically. The overall friction of the engine is reduced due to the small number of light weight moving parts, and the use of ball bearings throughout. The flex rod is nearly frictionless as the flexing is like a spring in which the energy required to flex it is returned in equal amounts.   

This engine may be made in a variety of configurations and sizes. For example, one can change piston size and stroke length in a matter of a couple of minutes. One cylinder may be substituted for an air pump cylinder to provide air or water pumping. It can have one or a plurality of cylinders without increasing the number of bearings.  Modern materials and methods have been applied to this steam engine to achieve new results and to bring steam power up to date.

Two Cylinder Direct Drive Generator

The engine shown below is especially designed to operate with solar collectors or a small boiler including household pressure cookers. It produces sufficient speed to eliminate belt or gear drives and operates on 10 to 50 psi of steam pressure.  

  The engine fits nicely into a tube for compact designs.


As seen in the photo below, this 2 cylinder engine/boiler combo produces up to 500 watts at under 20 lbs of steam pressure. The boiler water is automatically maintained and the heat from the exhaust is recycled back to the boiler. Distilled water and hot water is produced as a bi-product. The boiler is a modified pressure cooker with a self-feeding pump. It can be operated on a wide range of fuels. It is extremely economical to build and operate. It is perfect for survivalists, remote power, disaster relief and areas that are underserved by the grid. Licenses are also available for manufacture.


< >Click on the link for a video of the engine below.

Water distiller/heater/generator operated by small 2 cylinder steam engine

 This device produces many gallons of distilled water a day while it charges batteries, makes domestic hot water and heats space. Distilling spirits and food cooking are additional functions  for this system.  It employs an ordinary household pressure cooker or a small water tube boiler on a low simmering fire. Its closed-loop system recycles the exhaust heat and maintains the water level in the boiler for high efficiency. This model steam engine operates the system on 2.5 to 30 psi of steam pressure. The system is scalable for larger requirements. License is available.


New e-book just published by Robert Green

"Steam Age Machines" contains descriptions and 100 fine etchings and drawings of late 1800's industrial machines and steam engines. The beautifully detailed etchings are of framing quality and show the highest point of the technology. The pre-OSHA machines reveal the innermost workings of the gears, flywheels and structure before safety regulations hide them from view. This book also gives a brief history of the steam age and the contribution and legacy that is still in use today. In the last chapter it lays out the possible future of technology and its relevance for future generations of steam power systems.

Download it here: Steam Age Machines


Licenses are protected by Utility Patents, US patent # 6,647,813 filed 2001 (expired). US patent # 8096787 filed 09/08/2008. PCT/US2009/048038, Indian patent # 313376.

For information about obtaining manufacturing licenses, go to the "Licenses" page.

Look on "Licenses" page for FAQ's

Do to recent retirement of the present owner, the four patents listed above are now available for purchase. Inquire by sending an e-mail or a phone call to: 949 581 2529, E-mail: mailto:rgreen999@comline.com

See Products Page for Purchase of Patents and Technology

 For additional information about licensing or purchasing plans, send an email to:mailto:rgreen999@comline.com


Contact information:

Robert Green (949) 581 2529


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