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by state_less 1811 days ago
Yes, solar is dirt cheap energy and you wouldn’t need much of a battery (or any?) in this case, since you can store the excess product water in a tank.

I power my water maker with about 1400 watts and can make 35 gallons an hour. The panels, electronics and water maker were ~ $5000. I did the work myself at a slow pace, so not sure what the labor costs would be.

I set my system up in about 2 weeks. The requirements are a bit of time, seawater access and some capital.

https://seawaterpro.com/

2 comments

$5000 in a third world country is quite a lot.

For context, according to CEIC data [1], the average salary in Algeria is about $300 per month. That "dirt cheap" project of yours is more than a year's worth of labor.

Locally priced goods may be cheaper, but the US does benefit from a more direct shipping line with China (where most of these products come from, especially cheap solar panels). There's repair costs to be taken into account and if these become a necessity, you'll also have to take into account some kind of protection for when those without the means to buy one of these setups become desperate.

It's true that solar is relatively safe and cheap compared to other power sources, but projects like these are difficult to map to places where they can make a life-or-death difference. If things were that easy, we'd probably cover a patch of Sahara desert with solar panels and power the entire African continent for decades, with power to spare to export to other continents.

[1]: https://www.ceicdata.com/en/algeria/average-monthly-wages

Yeah, it’s tough out there. I think the capital cost might be around $15 to $40 a month depending on how generous the lender is.

Evaporative is interesting too, but solar isn’t too bad to maintain. Most of the maintenance would probably be keeping the filters, pumps and membranes in working order.

That seems like a lot of cost and complexity for a rural installation in a 3rd world country. How does the water output compare with, say, spending $1000 a simple evaporation design? The size of the evaporation pool would be larger than 1400W worth of solar, but it's much simpler and easy to repair.
I agree there is more complexity, but it may be worth it. Making electricity buys a good deal of versatility. If you have a bit extra, you can run an inductive burner, charge your phone/laptop or charge a house battery (if/when you can afford one).

I think in either system, teaching the locals to setup the system and maintain it themselves is important for keeping the costs down.

But my question is, what's the cost benefit?

$1000 would buy a pretty large solar still and you can spend the extra $4000 on a solar phone charger if that's something the locals need. Meanwhile there's little that can go wrong with a solar still and if something does go wrong, they can likely fix it (even if temporarily) with duct tape. Losing their cell phone charger and cooktop to electrical failure sounds like less of a problem than losing their water source.

An inductive burner, cell phone charger, desalinator, etc all sound great on a $200,000 boat where the owner is wealthy enough to keep it maintained and probably keep spares. But putting expensive and complicated electronics in a village so remote that they don't even have reliable water seems like a mistake.

I wouldn’t discount people’s ability to do some basic electrical repair. And maybe the neighbors can lend you some water till you get back up and running.

You might be right though, if it’s remote enough and you have room, perhaps a solar still is the cheapest and simplest option. It seems like it would have to be very large to give comparable amounts of water. Do you know someone selling such kits?

In any event, maybe this gives folks some ideas for lowish cost options.