Concentrating solar power (CSP) for home

Historically, electrical power generation on a large scale has relied on getting a turbine to rotate, which in turn rotates a connected armature (wire windings) within an unchanging magnetic field (typically permanent magnets). (In motor terms, the armature would be the rotor, and the magnetic field would be provided by the stator.) Getting the turbine to rotate often involved (in fact, still involve) the burning of fossil fuels in order to boil water. Steam then pushes the turbine. Later the steam is collected later in the loop, allowed to cool, and then returned to the water reservoir. More modern and renewable alternatives are found in hydroelectric dams and wind turbines.

A major exception that comes to mind is solar power generated through photovoltaic cells. Instead of taking mechanical power and turning it into electrical power, photovoltaic cells absorb photons to excite electrons (assuming the photons are of sufficiently high frequency). Commercially-available solar panels tend to be of relatively low efficiency (<20%), although far more efficient solar panels are being researched and developed.

Concentrating solar power (CSP) takes us back to our heat-a-fluid-and-then-have-it-flow-around-in-a-loop roots. Well, not exactly, and not always. Steam turbines are indeed used for solar thermoelectricity, but CSP has also been used on air turbines, photovoltaic cells, molten salts, and Stirling engines (described surprisingly well in Wikipedia). CSP is also being looked at as a way to desalinize ocean water into freshwater (very necessary as freshwater supplies continue to dwindle and ocean levels continue to rise).

In general, concentrating solar power is still more efficient than solar power from photovoltaic cells (ignoring possible future next-generation photovoltaics). Given the noisiness of a wind turbine in an urban setting, and the low efficiency of commercial solar panels (combined with the fact that this is Canada, with limited hours of sunlight already), I've always wanted a miniature CSP generator to play around with.

Amazingly, Sopology has a portable parabolic trough-style CSP generator. Additionally, they have a rooftop-mounted product as well.

Equally cool (or hot) and infinitely cheaper, if one is looking simply for a solar-powered heater to help keep costs down during a Canadian winter, is a self-made heater made partially from old soda cans.

Finally, I'm not sure how many people know this, but the bottom curve of a soda can is typically parabolic in shape. As such, if one can find soda cans that are not dinged up, a person could hypothetically polish the bottoms of soda cans until they are reflective and then build an array of parabolic mirrors. You never know what you could build... just think MacGyver...

Peace and long life.