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I'm only half kidding. I'm a bit of a prepper and I have lots of powerbanks and devices that charge from USB but besides idling my truck I really had no other way to charge any of them in case of a long-term power outage which seemed a bit of an oversight on my part.

Not like this solves the issue. 30 watts (under ideal conditions) isn't much but it's a start.

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[–] M0oP0o@mander.xyz 9 points 2 days ago (6 children)

What is 30 watts going to do for any of those? I don't think people here know how weak a 30 W panel is.

[–] Iconoclast@feddit.uk 5 points 2 days ago (1 children)

The argument was that: "basically nothing that you can charge is going to be of any use other than flashlights" not that 30 watts is sufficient for long term.

[–] M0oP0o@mander.xyz 1 points 2 days ago (1 children)

The one statement I replied to gave examples like refrigeration and HVAC that a 30w panel will not run. I made no commentary on what use can be made outside of flashlights.

That being said, as someone who runs 100w panels on my trailer parked on some land, 100w is not much other then topping off a deep cycle battery to then run lights and a propane furnace and fridge. Not that it is not useful at anything, just that those rollup ones are generally used to charge a power bank for phones, lights, and such. One of the better uses I have seen is hooking up one to a car to keep it topped up while sitting. But if you are going to use a panel you need a battery and at that point why not go with a non flexable 100w panel that is about the same size or smaller?

[–] Iconoclast@feddit.uk 2 points 2 days ago (1 children)

are generally used to charge a power bank for phones, lights, and such.

That's exactly the use case I bought it for. In the picture I'm charging a powerbank. I'm intending to play around with a small-scale solar setup on my shed at some point but for now this is the one cheap investment that enables me to keep critical small electronics running indefinitely.

[–] M0oP0o@mander.xyz 1 points 2 days ago

Check out some auctions, estate sales and such for some deep cycle batteries, solar charge controllers and panels. I have fixed my set up a few times over the years on the super cheap that way. The whole system is not bad other then the batteries for cost.

[–] HerbGrower@slrpnk.net 3 points 2 days ago (1 children)

My strimmer battery charger takes 65w. So 8 hours of 30w to charge a battery is almost 4 hours charging the strimmer battery which would probably fill it's small battery a few times over. If you are not depleting the strimmer battery multiple times a day, that is more than enough power.

You of course do need a battery to store it so many hours of solar are used in several minute short time loads.

[–] GoatSynagogue@lemmy.world 1 points 2 days ago (2 children)

A 30W solar panel is likely going to charge at about 5W, given the inefficiency.

[–] HerbGrower@slrpnk.net 1 points 2 days ago (1 children)

There is some inefficiency in charging a battery but not that much. Main losses would be that the solar panel isn't actually outputting 30w as you won't be getting ideal conditions all day.

But it doesn't necessarily matter either. 65w to charge a battery but you only need it once a week for an hour can easily be managed by 5w all day for a week.

Though planning for an apocalypse is kinda pointless anyway. Preparing for a disaster is more reasonable, such as a storm knocking out power for a while.

[–] GoatSynagogue@lemmy.world 1 points 7 hours ago (1 children)

The inefficiency isn’t the battery, it’s the panel. They run at about 20-25% efficiency at best.

[–] HerbGrower@slrpnk.net 1 points 5 hours ago

The rated wattage should take that into consideration.

[–] Iconoclast@feddit.uk 1 points 2 days ago* (last edited 2 days ago) (1 children)

I was getting around 12 watts during the sunset when I was testing it. It can probably reach around 20 watts under ideal conditions.

[–] GoatSynagogue@lemmy.world 1 points 7 hours ago* (last edited 7 hours ago) (1 children)

Highly doubtful. ~30% efficiency is already pushing the limit of solar panels. No way you’d get over 65%.

[–] Iconoclast@feddit.uk 1 points 4 hours ago

Efficiency means how much of the sunlight hitting the panels gets converted into electricity. How accurately manufacturers report the true output of the panel is a completely different thing. Plenty of reputable brands reach the advertised output.

[–] Snapz@lemmy.world 3 points 2 days ago (1 children)

Person I was responding to said nothing that can be charged, not specifically charged by 30 W. People live comfortably off grid these days with panels and batteries to store. Nothing perfect, but the right setup could matter if things went bad

[–] GoatSynagogue@lemmy.world -2 points 2 days ago (1 children)

We’re not talking about a whole off grid home here lol. We’re talking about a guy with a 30W solar panel.

[–] Iconoclast@feddit.uk 2 points 2 days ago (1 children)

You're moving the goalposts. You said nothing rechargeable besides flashlights isn't going to be of any use in the apocalypse which is an obviously false statement as demonstrated by the pushback you're getting. The size of the solar system wasn't part of the argument you made.

[–] GoatSynagogue@lemmy.world 1 points 7 hours ago* (last edited 7 hours ago) (1 children)

Interesting, because I said this

nothing that you can charge

“you” is you, the OP, the one showcasing his 30W solar panel.

[–] Iconoclast@feddit.uk 1 points 3 hours ago

You'd still be falsely assuming that I'm limited by the output wattage of the panel itself despite it enabling me to charge a powerbank that can output 150 watts.

I don't really understand exactly what you're doing here anyway. Like, do you just find people who get excited about things and then go piss all over it because that's fun or something?

[–] busted_Anoose@aussie.zone 2 points 2 days ago

do you have somewhere to be? if the power goes down long enough, it's not like you're going to be in a hurry. but yes 30w is pretty small. you can buy a 450w solar panel for under 200 bucks. add a inverter and 100ah battery and you're laughing. most shit you can run on dc like lighting and small devices.

[–] monkeyman512@lemmy.world 3 points 2 days ago

You just get to learn to be VERY patient.

[–] MIDItheKID@lemmy.world 1 points 2 days ago (1 children)

30w can charge a battery bank like a Jackery, and those can put out 1000w continously. It would take ages to charge, but it's more than nothing.

[–] Bluewing@lemmy.world 1 points 2 days ago (2 children)

It might be better than nothing for some things, but providing enough power to run heaters as needed when it's -20F outside over the next week ain't going to happen. And while it would work for an LP furnace for a while, that tank WILL go empty, and then where do you get more fuel?

[–] MIDItheKID@lemmy.world 1 points 1 day ago (1 children)

I don't think a high wattage battery is something that could keep you warm. I was talking more like creature comforts. Not something you would want on-the-go because of the weight, but if you were hunkered down you might at least have lights or some amount of entertainment. Shit, it could even power a tablet, router, and NAS, and give you something to watch in dark times. That's a good thing to have on solar power if you are staying put.

[–] Bluewing@lemmy.world 1 points 1 day ago (1 children)

It will keep you warm for a little while, but not for long.

If things hit the fan, lights can be a cheerful thing to have. But if it's a widespread power outage that lasts, the internet goes down, and cell service follows pretty quickly. Maybe a Game Boy is usable, but your tablet will be a paperweight, and forget the NAS. On the upside, there just won't be much you are going to need electricity to run at that point.

[–] MIDItheKID@lemmy.world 1 points 1 day ago

I'm saying watch movies on the tablet off of the NAS. That should work perfectly fine with no internet. You would only need to power the NAS and router. And charge the tablet.

[–] Iconoclast@feddit.uk 2 points 2 days ago (1 children)

Burning wood seems like the obvious solution to keeping warm in the winter. There's much better uses for the little solar power there is available then.

[–] Bluewing@lemmy.world 1 points 2 days ago

Burning wood comes with its own extra work and costs. Plus the danger of burning your house down. I live in a forest, and wood heat is not uncommon here. There were 4 wood heat fires that destroyed homes this past winter, it was a cold and long winter this year. And I did grow up with wood heat as a kid, so I'm very familiar with it. I do remember a couple of chimney fires quite well.