70% of the average household's energy bill is spent on heating and hot water. By focusing sunlight on a linear boiler (with a parabolic trough or linear fresnel reflector), making steam and putting that through an efficient steam turbine connected to a permanent magnet alternator, and a condensing thermal storage tank it is possible to make heat, hot water and electricity at higher efficiencies and lower cost than using photovoltaics. Additionally, this design utilizes an analog tracking system that requires no electricity, uses solar energy to create movement and operates on fluid logic. In the next iteration steam jet ejectors will drive a chiller for cooling operations.

Currently there are no solar focusing steam electrical generation systems on the market designed for household heating, cooling and electrification (though the system is not limited to said use). What makes this project novel is that for the most part it is made from common materials and can be built by almost anyone from first world residential power consumers to off-grid third world consumers. The market potential for this style of collector includes anyone who desires to have a stable energy and heat source who can't afford a complete photovoltaic system. Further iterations will be useful for cooling and heating of containers as well as interplanetary applications. Enhanced public safety is achieved by reducing demand on the grid during peak usage and improved quality of life for anyone interested in non fossil energy systems.

This system is capable of running in an open or closed rankine cycle or with an organic rankine cycle. When the components are appropriately scaled to the application and environment the device can be optimized for heating, cooling or electrical production. Using the open license model for development this will lead to further products developed by others.

The unit shown is for demonstration and requires further development and refinement for most efficient operation. My next steps are to add an evacuated tube linear receiver at the focal point and make a larger optic to gather more energy to heat and cool my own house as a proof of concept. Additionally, a grid tie inverter would allow the user to run their electrical meter backwards or charge batteries for night time electrical usage and an evaporator driven by steam jet ejectors will make it possible to cool the home or keep food cold for safe storage.
My intention is to make this design available with an open license so that anyone can build their own and continue the development toward more efficient energy systems using this concept. Further, I intend to manufacture a more efficient turbine for anyone to buy and use on any solar thermal system for electrical generation or mechanical power.

Plans will be available for anyone who wants to build a similar system from scratch or from components purchased from others. I estimate that this turbine system will cost 25% of photovoltaic systems with similar energy output.


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Energy, Generator, Power, Solar


Name: Matthew Davis

Type of entry: individual

Profession: Engineer/Designer

Number of times previously entering contest: never

Matthew's favorite design and analysis tools:
Ball Point Pens, Unigraphics, prototypes.

Matthew's hobbies and activitiess:
solar experiments, gardening, furniture designing

Matthew belongs to these online communities:
Linked In, Facebook

Matthew is inspired by:
I want to make a more efficient lifestyle for my family and a cleaner world.

Patent status: none