Trying to figure out why solar backup batteries are so expensive. It's like $28,000 for 20KWh worth of batteries+install. My car has a 70kwh battery and cost only a bit more than that new.
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Tariffs
aug 21, 2025, 6:03 pm • 0 0 • view
Are you comparing to the price of the car or to the price of the car’s battery?
aug 21, 2025, 6:55 pm • 0 0 • view
The price of the car
aug 22, 2025, 4:21 pm • 1 0 • view
To be clear, the price of the battery is not just the battery, but also install
aug 22, 2025, 4:22 pm • 1 0 • view
I think you're supposed to source them directly from China they are crazy cheap now if you do your own BMS AFAIK
aug 21, 2025, 7:09 pm • 3 0 • view
Just bought and assembled a 5kwh battery and hybrid inverter for 1700. 3 more 5kwh batteries would run me another 2400. Sir, my belief is you are paying for labor guarantee, warranty and expertise of installers.
aug 21, 2025, 6:04 pm • 7 0 • view
Hm... Unfortunately my township has a law against doing unlicensed electrical work, but maybe I can figure out a way to get it all done on the cheap
aug 22, 2025, 4:19 pm • 0 0 • view
Understandable. Expanding on my purchase: its fully off-grid backup. So its not grid tied. Had an electrician install transfer switch for a backup generator and RV shore power decades ago, making my battery system a replacement for the generator, without any new electrical work.
aug 22, 2025, 4:25 pm • 0 0 • view
I see. I'm looking for something that hooks to the grid, or at least integrates seamlessly to the grid
aug 24, 2025, 3:26 am • 0 0 • view
but you would still need a certified electrician for this bit.
aug 24, 2025, 3:57 am • 0 0 • view
I'm generally certain that with something like the eg4electronics.com/categories/i... (a gateway) you can combine many sources of power and intelligently power your home and the grid. doesnt require use of their batteries or inverters either, if im correct.
aug 24, 2025, 3:56 am • 0 0 • view
Can you point me to what you bought?
aug 22, 2025, 4:19 pm • 0 0 • view
www.mobile-solarpower.com/mobile-48v-s...
aug 22, 2025, 4:30 pm • 0 0 • view
do you need 20kwh? i installed a 5kwh jackery system with grid tie-in (no solar panels) for under $5k enough to back up critical utilities (sump pump, lift station, gas furnace blower, internet) and both kitchen fridge and garage freezer for days
aug 21, 2025, 5:45 pm • 1 0 • view
plus my hyundai has a 77kwh battery and supports v2l so i can top off the home backup from that if needed
aug 21, 2025, 5:46 pm • 1 0 • view
I chose the number mostly for illustrative purposes, because the price I was quoted for 20kwh happens to very closely align with the price of my car. The other option I was given was 10kwh for half the price, so it's still stupid expensive.
aug 21, 2025, 5:56 pm • 6 0 • view
Right, but if you want to power your home off solar (or as much as you can at least) you want a larger battery to even out your production/use.
aug 21, 2025, 5:54 pm • 1 0 • view
that’s why i asked if 20kwh is necessary. depends on what you’re trying to do.
aug 21, 2025, 5:55 pm • 0 0 • view
That's what I'm going for here. I haven't done the math because as soon as I saw the prices I was like "no way". But I think I would need more than 10kwh to avoid having to draw from the grid under the large majority of circumstances.
aug 21, 2025, 5:57 pm • 0 0 • view
Again, it just seems strange to me that it's so much more expensive per kwh than my car, which I would think has a lot more going on than a home backup battery. If I could hook up my car battery to my house (I cannot), I would probably never need to draw from the grid.
aug 21, 2025, 5:58 pm • 1 0 • view
A combo of low onshore production, regulatory costs, and extremely high labor costs.
aug 21, 2025, 5:51 pm • 0 0 • view
They are prohibitively expensive. California provides tax credits but the out of pocket expense is still pretty high. There are some excellent portable solar generators that can power a refrigerator and lights for about $2000-3000.
aug 21, 2025, 6:01 pm • 2 0 • view
I’d start with this channel: youtu.be/oisSDHpgld0?...
aug 21, 2025, 6:05 pm • 1 0 • view
agreed.
aug 22, 2025, 9:31 pm • 0 0 • view
£3400 in UK. www.renewsolar.co.uk/product/20kw...
aug 21, 2025, 10:27 pm • 0 0 • view
Few people have flagged "get a smaller home battery and get an EV with vehicle to home" as the optimal solution.
aug 24, 2025, 11:14 am • 0 0 • view
Using a car battery for solar (with precautions) While not ideal, it's technically possible to use a car battery for solar energy storage in certain situations, but with crucial precautions
aug 21, 2025, 5:56 pm • 1 0 • view
Using a Marine Battery (Deep Cycle) would be a bit safer with solar
aug 21, 2025, 7:27 pm • 1 0 • view
Use a charge controller: A charge controller is essential to regulate the voltage and current from the solar panels to the battery, preventing overcharging and potential damage to the battery and connected appliances
aug 21, 2025, 5:56 pm • 1 0 • view
Avoid deep discharge: Limit the depth of discharge to extend the battery's life. Monitor the battery: Regularly check the battery's state of charge to ensure it's not being over or undercharged
aug 21, 2025, 5:57 pm • 1 0 • view
Heard about this in the last week, but there's apparently a growing secondary market for used EV batteries as grid storage, might be worth checking out
aug 22, 2025, 1:45 pm • 0 0 • view
First Google cursory hit shows a 46kWh for $2099, no info to offer you on legitimacy of this specific website www.greentecauto.com/product-cate...
aug 22, 2025, 1:45 pm • 0 0 • view