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by lowtechmagazine 2671 days ago
My article shows that heating without electricity is cheaper and more efficient than heating with electricity. It also has references to back up these claims. What you write is simply untrue.
1 comments

The math kind of backs it up the efficiency of solar power backed electrical heating over wind.

Sunlight has a power of ~2kw/m^2 in visible spectrum (solar panels cannot capture all of this). At a strong breeze (10m/s) wind has a power of ~1kw/m^2 (windmills cannot capture all of this). So the mechanical heat generation would have to be more than twice as efficient to electrical generation to be worthwhile. But the "complications" mentioned are really what kill wind.

You want to capture sunlight: solar panels on the roof. No real obstruction.

You want to capture wind: massive windmills on your roof, need to disable the fan blade if the wind exceeds a certain value. Moving parts wear out.

I am not going to install a 2m radius windmill on my roof. Two 1m radius windmills have 1/2 of the area and are still an eye sore. Four 1/2m radius windmills, 1/4 of the area of the 2m radius blade.

> Sunlight has a power of ~2kw/m^2 in visible spectrum

FYI, solar radiation is more like 1050 W/m^2 on earth's surface, of which about 40% is in the visible spectrum.

https://en.wikipedia.org/wiki/Sunlight