This is such a clever idea for people with big yards. Practical Solar sells computer controlled heliostat mirrors that track the sun and aim it into your windows. Each heliostat can provide 600 watts of heat and as much light as forty 100 watt bulbs. If your house is well insulated then you should retain a fair bit of the heat into the evening. Finally that big front yard can be used for something.
A controller and your computer keep up to 200 heliostats aimed throughout the season, although that might set your house on fire.
But in case just shining through the window is too simple and elegant a solution, Practical Solar has other ideas:
-Building heating and cooling (HVAC)
-Potable hot water heating
-Air conditioning (with hot water-driven absorption chillers)
-Hydrogen (H2) production (for fuel cells)
-Low temperature industrial and agricultural applications (e.g. drying of wood, grain, leather)
-Powering a thermal engine
When photovoltaics or solar water heating systems are left outside in more northern installations they can get covered in snow. The great thing about a heliostat is that it can point the energy of the sun onto anything, be it photovoltaics mounted on a wall or a tank of water or trombe wall inside your house.
More information at Practical Solar, via Eco-Geek and Greentech Media
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