
In Nigeria, Solar-Powered Fridges at Outdoor Markets Save Food from Spoiling - curtis
http://gizmodo.com/in-nigeria-solar-powered-fridges-at-outdoor-markets-sa-1737306287
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paulmd
The text of the article mentions cold-rooms but the picture shows freestanding
refrigerators. For small-scale storage they should should be using front-
opening/chest-style refrigerators instead of freestanding ones.

Since cold air is denser than warm air, it falls. That means that every time
someone opens a freestanding fridge a significant amount of your cold air
falls right out. Top-opening fridges provide a well that retains the cold,
significantly reducing energy usage especially on fridges that are frequently
opened.

You see it a lot on freezers because the air is much colder and the cold tends
to fall out even faster as a result. I think it would produce improvements
here as well, since the energy produced by a solar panel is rather limited.

Assuming you could protect the cooling system and provide sufficient airflow -
could you operate a fridge flipped on its back? Or does the compressor depend
on proper orientation to have gravity return coolant and so on?

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ZeroGravitas
I've seen an article online where an "off-grid" home powered by solar re-
purposes a chest freezer into a fridge for the very reason you state.

[http://newlifeonahomestead.com/convert-chest-freezer-to-
frid...](http://newlifeonahomestead.com/convert-chest-freezer-to-fridge-
solar/)

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Asbostos
I wonder what the novel feature is here. Surely somebody would have thought of
renting space in a solar powered fridge before? Maybe it's only recently
become viable because of improvements in the economy?

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ZeroGravitas
The cost of solar panels (and batteries) has been dropping at a reasonable
pace and is set to continue to do so for a while, so there's probably a whole
bunch of "solar powered X" businesses that will become feasible as time goes
on.

There's some nice synergies here, you need the refrigeration most when the sun
is shining brightest, a well insulated fridge acts as a kind of battery, the
solar panels shade the fridge from the sun, and so on that are strangely
pleasing to some aesthetic sense of mine.

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lscharen
Interesting that the article specifically mentions that the solar panels feed
and inverter first, and then power the refrigerator. There are refrigerators
designed to work directly off of 24V DC, which would seem to be a more logical
choice.

[http://m.alibaba.com/showroom/24v-refrigerator-
compressor.ht...](http://m.alibaba.com/showroom/24v-refrigerator-
compressor.html)

These are less common, though. Maybe cheaper commodity prices for AC-powered
compressors offsets the additional inverter cost and efficiency losses?

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warfangle
You can cannibalize an AC compressor from a car. Alibaba has AC-compressors
for as little as $1/pc. They are much cheaper, and much more common.

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Johnythree
Most car A/C compressors are belt driven from the engine, eg no electric motor
so not much use for Solar operation.

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warfangle
That's a good point - I didn't realize that. Still easy to cannibalize if you
have an AC motor :)

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1ris
Are batteries involved? Or is the insulation simply thick enough the keep the
food cold enough during nighttime?

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gambiting
Bear in mind that in many "hot" places the temperature during the night falls
down to nearly 0C, so it's probably enough to stop the food from spoiling.

