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Comment by quechimba | Hacker News Reader

Many families in the nearby village run generators at night. They can't afford solar panels so they pay 5 soles for gasoline just to have lights on when it gets dark. If they could afford solar they could have lights on every night for a one time cost. Most family don't have the luxury of running generators though.

This project sounds really cool. I wonder if this can be done in the Peruvian Amazon. I'm sure several families could share the same solar panel and battery if they only use it for lighting and charging phones... Funding would be difficult, no one has money here.

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I can get quite a lot of night time light out of a $65 100Whr lipo and a $50 inverter. That sounds much better to me than a generator.

You can get quite a of of it, at that price. Shipping to a remote island in the middle of nowhere, is more expensive.

In my mind I was comparing versus the alternative stated of buying a generator & fuel for it. The generator will be up-front pricier, weightier, and bulkier, by far on each count. So it still seems like a huge win to me versus what's available now, if the use case is as described.

I'll try to find out how people could afford buying generators. Solar shouldn't be much more expensive but I can't find any prices online.

I think there's also the sunk cost aspect. You saved for a long time for the generator on the basis it would provide power for you for a very long time so an alternative to this prized asset isn't high on your list of things to spend all your savings on (even if on paper it was economically rational to do so)

That's half the monthly minimum wage, most people here make even less, and everyone has at least a few kids to feed.

Also everything is more expensive because it's so remote. There are no roads so everything has to be brought here by airplane or boat. If you order something from Amazon (the website) to the Amazon (the rainforest) shipping is at quite expensive and then there's import fees too...

Uh huh, and how expensive, heavy and bulky was the generator and the fuel they have to constantly feed it?

If they need/want more than just lighting, then fair enough. But for just lighting, rektide's proposal blows a generator out of the water.

Most houses don't have generators. Maybe I should have been more clear.

Genuine question: isn't an inverter an unnecessary cost and relatively inefficient versus a lower voltage light (i.e. roughly matching the battery)?

I read somewhere that a DC to AC inverter wastes 5-15% of the energy.

I guess what is needed to run lights would be a solar panel, a battery and an MPPT controller.

An inverter is an inefficiency & a cost, yes.

Yet. It's daunting to me to imagine replacing well known infrastructure with something custom & different. You could try to get a bunch of automotive 12 & 24 lights but there won't be great fixtures. You also need 12v versions of most appliances; fans, fridges, others.

Your upgrade capabilities also seem limited. If grid power does come, you might be stuck with a bunch of abornal choices. Your wire loss is much much higher with 1/10th the voltage or 10x the amps per wire, which limits scaling out on DC, is a counter-inefficiency that grows the bigger your system gets.

I think it's a good idea. Personally if I built a small off grid home or RV I'd probably do 48vdc. But it'd be much more work & require a ton of expertise.

Sure - agree that for a whole house, it’s far more complicated. I was more interested in you running “a light” at night with a LiPo and an inverter.

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