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Green Collar Careers - Future Solar Heat Products

One of the "hot new technologies" that's been emerging from a 200 year slumber are Stirling Engines.  These engines are among the few that can be powered directly from solar energy.  Some large scale systems are currently generating electricity in the Mojave desert with that electricity powering homes in San Diego.  Smaller scale systems are in trials today with excellent results.

The Infinia design clearly stands out among the rest as there are virtually no friction parts in the engine.  Incredible as that may seem the design uses close tolerance components and rather then bearings to guide the piston in the cylinder it employs an ingenious device to maintain precise alignment.  As a result no oil is required nor does it require any service for an estimated 25 years.  This design was first tested over 20 years ago.

The cost of these systems are currently estimated to be in the $6 per watt range and given dedicated mass production projected costs are in the $3 a watt range or less.

The current systems are directly heated by the sun using a tracking parabolic mirror.  The focused heat of the sun produces temperatures in excess of 1000° to heat the working gas Helium, and the system is totally sealed with the generator inside the Helium environment.

The video above shows a cross section of how this Stirling Engine Generator works.  Like all solar powered devices the current configuration only produces electricity when the sun is shining.  However by storing the thermal energy in a heated mass a Stirling Engine generator could run 24 hours a day.  The cost of a thermal storage mass is much less then batteries giving some significant advantages to this system.  Watch the Infinia Solar Video.

The Infinia system is tooling up for mass production with deliveries planned by the beginning of 2010.  No doubt these systems will spawn the development of parabolics used to heat water.

Europe has been promoting the development of Micro Combined Heat and Power (m-CHP) appliances that currently operate on combustible fuels from natural gas to wood.  Using a Stirling Engine Generators they produce electricity very efficiently with claims of lower costs then commercial AC at retail prices.

Tracking Parabolic collectors are on the rise, particularly with ground mounted systems.  As the cost of drive systems has plummeted with a significant improvement to reliability, parabolic systems are beginning to rival flat panel cost with major improvements in thermal production at times of low solar energy availability - such as cloudy days and when the sun is lower towards the horizon.

In colder climates Solar heating has been slowly catching on and requires quite a bit more energy then water heating.  Tracking Parabolics systems have been gaining some excellent results in the Nordic region and should be commercially available in the United States by 2015.

China has long been an advocate of using the solar water heating and some systems from China are now SRCC qualified with more coming.  India has more recently taken an interest  in solar water heating and no doubt will also become a low cost source in the coming years.