
Odeillo solar furnace - andrelaszlo
https://en.wikipedia.org/wiki/Odeillo_solar_furnace
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bjoli
Talking about solar furnaces: if you are a house owner there is a lot of
heating costs to be saved from building your own solar furnaces for air or
water. Solar electricity is pretty ineffective (at most about 17% in
commercially available solutions) whereas home built air heaters sometimes get
up to 40% and water heaters almost 80%.

A friend built a solar air heater (2.55 M2) that gets almost 1kw of energy out
in late February with -5c outside.

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kovrik
Dumb question: is there any difference (in terms of costs and effect) between
solar panels and solar furnaces?

I mean, say you have N square meters of solar panels. If I understand it
correctly, then it doesn't matter whether you make them flat or turn them into
parabolic solar furnace, does it?

Yes, with furnace you can concentrate that energy on smaller area (hence more
heat), but does it matter for house owners?

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bjoli
A solar "furnace" for air heating is just a box with a collector (most
efficient ones are regular black insect screen collectors), which makes them a
lot cheaper than a solar panel. Depending on how you have to transfer the air
into/out of he collector the price difference can be huge.

I am building one now where the material cost for 5 m2 of collector with
ventilation will be just shy of $650 and then I am using a very fancy
collector mesh which I am not even sure will bring much. The ventilation will
also be expensive in my case. Similar panels can be made a lot cheaper,
especially in the US where material is cheaper and more readily available.

That size would give me about 850w with solar electricity panels and I am
counting on 2kw with my collector (if I can get air through it quickly
enough).

For my size (5m2), the price difference is about a thousand dollars, and I
will get twice as much energy out of it.

You should check out www.builditsolar.com

and search on YouTube for solar furnaces.

Edit: oh, and solar water heating is of course even more efficient. 300m 4cm
matte black PEM pipe on your roof is an excellent 10kw pool heater, costing
just a couple hundred bucks. Payback is just a month or two depending on how
fancy you want it.

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torpfactory
Somebody was reading the Parker Solar Probe link that was posted earlier today
:).....

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defterGoose
Lol, I Googled it when I read it too. How can a name like Odeillo Solar
Furnace not pique one's curiosity?

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0xdada
Wow, looks awesome. Has anyone visited, by any chance?

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colinb
There's a group of three such power stations near Las Vegas. I passed them on
the way from LA a few months ago.

[https://en.wikipedia.org/wiki/Ivanpah_Solar_Power_Facility](https://en.wikipedia.org/wiki/Ivanpah_Solar_Power_Facility)

I don't know if they permit visitors. There's something odd about the way the
light makes the air glow near them. From a distance, they look unearthly;
almost CGI'd.

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ryandvm
Saw this installation on a documentary a few weeks ago. Unsurprisingly the
thing is capable of instantly frying any bird that happens to fly though the
beams.

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singularity2001
Which materials withstand temperatures of 3500 deg?

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zaarn
Tungsten-alloys (Lightbulbs) and ceramics (Reentry Shields) are usually up on
the list of materials that can withstand these temperatures, lately carbon
nanostructures also joined it (Parker Solar Probe).

