I've been thinking about investing to reduce energy costs, I'd appreciate some insight.
My budget is 10万円 and want to set it up only on my aircon. My most expensive month was 12,495円 after a year in my current place.
After my initial search, I like this panel and battery. Based on rough calculations, I think it would save roughly 10% monthly at a minimum. I could be wrong since my electricity usage on the weekends almost doubles. This would mean at most it would take 4 years to pay itself off using 10万円 as investment price.
I feel like I'm missing something or this setup is overkill for my use case.
I'd like to hear your thoughts, thanks in advance!
Edit 12h later: thank you to everyone who commented, it helped me understand the subject deeper. There is no reality where this investment is worth it since even at a perfect theoretical ROI is too long. Need space for solar to be worth it
by Ill-Pride-2312
6 comments
A 100w panel will barely put a dent into your usage, especially on a balcony it’ll barely get any charge. And that battery at full charge will barely run the AC for even 2 or 3 hours
I’m severely skeptical of your plan… I haven’t run the numbers , but it looks like a 1500w battery and a 100w solar panel. Probably take you 1.5-2 days to charge the battery and 1-3 hours to run it down.. saving you what? 75 yen? This doesn’t include the hassle of setting it up.. and replugging everything up.. why dont you just invest the money instead?
Edit: I’m wondering if I was extremely optimistic on the charge rate too.
So the battery can power your aircon for 40min to 2h depending on how strong it’s running. The panel will barely charge it over a day. Best case you can save 1kwh (30-40yen) per day
There’s no way you can amortize the cost in 4 years, with an obsolute best case scenario.
You wan to check about the battery charging too. Can it feed grid power when empty ? Can you instruct it to charge over solar and only top up usage with grid ? Do you have to plug/unplug the aircon everytime ?
That panel can probably power a laptop for 8 hours a day.
ACs tend to have spike usage, like initially consuming 2kW and going back down to 200 after it has reached the temperature. This is typical for my 12 jyou living room AC that has insulated double pane windows at 28C.
It typically takes about 8 to 10 years for a solar panel to “pay for itself” in terms of energy savings.
If you want to do it for fun and to learn something about electronics, go ahead. If it’s for money – bad idea, you likely won’t even break even.
Don’t try to hook it up to an outlet, 100V is still plenty to be dangerous and wiring here can be a bit… funky. Even if you were allowed/able to, you would not save much if anything. When you get a lot power, the grid also does and demand/price is low.
I have a delta 3 plus and I don’t think you can run an AC off of it since the max output is about 1500W (X-boost drops the voltage which a compressor won’t like) The capacity of the battery is around 1000W and with DC to AC conversion you’ll have inefficiencies. So you’d be looking at running the AC for maybe 30 minutes.
Solar wise a 100W panel can jusssst about keep a fridge going, but again you’ll get maybe 6 hours of daylight and maybe 82W on a good day.
Not really feasible with that system. If you’re really interested in powering an AC you might look at the Delta 3 pro. But it’s almost 5 times the price.