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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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[–] danekrae@lemmy.world 38 points 3 days ago (3 children)

Have you calculated how long it takes/took to pay for itself?

[–] IcedRaktajino@startrek.website 44 points 3 days ago* (last edited 3 days ago) (1 children)

All of the labor has been DIY, and I've got about $9,000 invested in the system components.

Back of the napkin math, at current electric rates, puts my ROI at just under 9 years. If electric rates keep going up, it'll pay back even faster.

Edit: Depending on how you look at it, ROI could be in as few as 1.5 to 2 years. This system is in lieu of a whole house generator that would have cost us about $7,000. Had we gone with that instead, it would never have paid for itself (other than peace of mind) and we would have been perfectly content. So if I'm only considering the price difference between this and the generator, it'd only have to pay back $2,000.

[–] LincolnsDogFido@lemmy.zip 13 points 2 days ago (1 children)

Yeah, buying peace of mind when it comes to self sufficient power generation has no price tag. Decentralization of the grid is a good thing regardless of if you "pay it off" or not.

[–] merc@sh.itjust.works 6 points 2 days ago (1 children)

buying peace of mind when it comes to self sufficient power generation has no price tag

$10,000? $100,000? 75% of your salary for the rest of your life?

It obviously does have a price tag at some point. If someone wanted true self-sufficiency they'd have to get a full solar setup plus a generator in case the grid went down at a time when solar power wasn't covering the needs. (That's likely if, for example, your power is knocked out due to wildfires, and the wildfire smoke is making the solar setup unable to produce power.)

And, you can't really consider yourself fully self-sufficient when it comes to electrical power unless you have a n+1 setup, so you have a backup generator in case the primary one fails and needs to be repaired.

[–] 0x0@infosec.pub 1 points 1 day ago* (last edited 1 day ago)

Sure if you want to be hyperbolic about it, but in my experience with people that argue like that, they will also say dumb things such as government owned entities such as schools, public transport, postal service or water access needing to make profit or its just all bad ..

[–] Dookieman12@piefed.social 22 points 3 days ago (2 children)

If you enjoy it, it already has.

[–] ripcord@lemmy.world 5 points 3 days ago (2 children)
[–] Eyekaytee@aussie.zone 4 points 3 days ago

have battery system and solar since jan 2023, still love it

[–] Dookieman12@piefed.social 1 points 3 days ago (2 children)

Time, in hours (H), equals average solar kilowatt hours per month (K), multiplied by the price of one kilowatt hour (P), divided by the total cost (C) of all the purchased components.

H = (K * P) / C

[–] wunami@lemmy.world 4 points 3 days ago* (last edited 3 days ago) (1 children)

Time, in hours (H), equals average solar kilowatt hours per month (K), multiplied by the price of one kilowatt hour (P), divided by the total cost (C) of all the purchased components.

H = (K * P) / C

So you're dividing the average saving per month by the total cost and expecting to get hours?

If we generously estimate a very high 3000kWh/month generated and high $0.40/kWh price and it cost OP $9000, then you formula is (3000×0.40)/9000 = 0.133 hours.

BreakI ng even after less than 1 hour?!??! Extraordinary!

[–] Dookieman12@piefed.social -1 points 2 days ago (1 children)

It's pretty easy to cry about bad math, but it's a lot harder to figure out the right math.

Don't worry, I'll try to do it for you again a second time.

Power consumption varies. Use the average monthly power draw from the solar array, let's assume for demonstration purposes 1,000 kWh/month.

Multiply that by the cost of 1 kWh from the power company, let's say 20 cents.

In one month, that means you saved $200.

Let's assume the solar equipment costs $1,000.

The answer is 5 months, or 5,000 kWh.

Sorry, I'll make sure the free work I do for you is better quality next time.

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

Bro. Don't act like this basic arithmetic and unit cancelation is hard. Not my fault you were so confidently incorrect.

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

Or I could read the comment where he said

[–] Dookieman12@piefed.social -1 points 3 days ago (1 children)

Then do that instead of asking random people who aren't in any position to know.

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

It was more of a comment on your comment

[–] huppakee@lemmy.world 5 points 3 days ago

I get you but it was worth the money you spent ≠ it earned back the money you spent.

[–] mrsilkworm@piefed.social 14 points 3 days ago

A hobby pays itself just by enjoying it. I've never calculated how long it will take to pay off my gaming rig