Solar + power bank for household appliances in apartment - can I reduce my electricity bill?
Comment box Scope: exploring a wacky idea Tone: being open-minded Opinion: none Sarcasm/humor: a couple dry jokes I watched the video "Dirt-Cheap Solar Generator Setup - What Can It Power?" by...
Comment box
- Scope: exploring a wacky idea
- Tone: being open-minded
- Opinion: none
- Sarcasm/humor: a couple dry jokes
I watched the video "Dirt-Cheap Solar Generator Setup - What Can It Power?" by Alex Beale yesterday. In the video, the presenter purchases a cheap solar panel and power bank for a total of $250 and tests household devices to see what kind of wattage it can take.
Turns out the cheap device can power most household objects. I'm curious if it's possible to try a similar setup to meaningfully cover my electricity usage on a day-to-day basis. Unlike the creator of this video, I don't have a yard. I'm exploring whether a solar solution could work with my constraints.
I wanted to share this idea with Tildes and hear any ideas/feedback/experiences from people who have tried something similar.
My goal
- Investigate whether it's feasible to save money with this setup
- If so, find a setup that I can use to power some or all of my household devices off-grid
- Pay less in electricity costs
- Be able to rely on my power bank when the building's power goes out
My current situation
- I live in an apartment in an urban area in the US northeast (southeastern Pennsylvania).
- I do NOT have a balcony (sadly).
- I have two south-facing windows and four west-facing windows (two of which get a LOT of light, two of which get a decent amount but not as much). However, my south-facing windows don't get direct sunlight most of the day since there is a building in the way (just a bit in the late afternoon).
- The dimensions of the windowsills are about 16 inches in depth and about 55 inches in width. That's enough for a small or medium-sized solar panel, but not most panels designed for outdoor use.
- I can open the windows all the way and it would be physically possible, in theory, to hang something outside rather than keeping it on the windowsill (we'll get into this...)
- I pay for all my electricity. The heat/air is central and inaccessible, as are a couple of the overhead lights (there are only a couple), but everything else could theoretically be replaced with energy from a power bank, I think.
- I already have a power purchase agreement with a renewable energy supplier. All my energy is "green" in the sense that I'm making it slightly more economically feasible to produce green energy.
- In a less expensive month, the bill might come to around $75. In an expensive month, it might come to around $350. If I heated the unit as much as I would like, it would be higher.
- I'm pretty sure most of my electricity use is the heat/AC.
- I'm pretty sure most of the remainder is the
washer and dryerdishwasher, followed by the washer and dryer. - I spend some amount heating my water otherwise (shower, sinks), but I can't address that with a solar panel.
- I wouldn't mind saving money on the rest if that's all that's feasible.
My power needs (I think)
- I don't know much power my oven uses. It's electric, which the internet says averages around 2500 W.
- My dishwasher runs at 120 V and 18.7 A. That is... uh... 2244 W. Also a lot.
- My dryer says 120 V on the machine, and if I look up the model number, it seems to be at 15 amps. So that's 1800 watts.
- My washing machine, uses....... IDK how many watts. No information on this thing exists. But it uses a 120 V outlet. The internet says an average washing machine could use up to 1400 W (sounds high, but okay).
- My computer has a 520 W power supply, but I doubt it ever uses that much. It's old and mostly runs Solitaire. Maybe one day I will get a fancy new machine that does like 1000 W.
- My fridge uses 115 V at 4.5 A. Let's pretend that's 120 V and say 540 W.
- I can't tell how many watts my TV uses, but the internet says it could be up to 200 W.
I would want a bit of breathing room with the rated wattage so that the power bank doesn't explode.
No way I can run all these devices simultaneously off the power bank, but perhaps I could time them. Even partial coverage could be adequate if it makes financial sense.
Possible spatial configurations
I see a few possibilities here:
- Stick a bunch of solar panels in the windowsills, propped up at a suitable angle.
- Stick the panel directly in the window like an air conditioner. In this case I would want to use a two-sided panel, since there would be some ambient light coming from the inside. This would inevitably reduce my home's energy efficiency, which I would have to account for.
- Weld some sort of counterweight to a mounting system that I can use outside the window to perch the panel at an ideal angle. This would also reduce my home's energy efficiency, but maybe by less since the gap could be minimized. It is also probably illegal. And dangerous.
- Just fill my living room with solar panels. I will need to have a conversation about that. But it could be done.
I think #1 is the only one that is actually reasonable. #2 would cost me too much in heating bills to make any sense. I think #3 would get me evicted or sued by the city. And #4 is unreasonable considering that I like to use my house to live in.
My budget
I would maybe spend $500-1000 on this if the payback period was a few years. Not more than 5 because panels by then will be a lot more efficient.
I guess I could spend more than that if it makes sense. I have good credit and a high credit limit. I don't make that much money but I could save for a bit or carry a balance for a bit. I think I would draw a hard line around $3000.
The power doesn't go out here too often, so that isn't the main selling point, more of a nice-to-have.
My research
I'm just looking on Amazon. I know I could maybe get something a little cheaper elsewhere. I'm searching for "power bank with solar panel".
- 4000+ W range: OUPES Mega 5 for $3300+ with panels (I think?). That's a lot of money for something that might not even work. And I don't believe it would be $3300, most other models I'm seeing are closer to $5000.
- 2200 W range: Jackery Explorer 2000 for $2500 with the 2 panels. Maybe this could cover my energy-intensive appliances, one at a time. Still expensive. The solar panels will... maybe fit in the window with about 1/2 inch to spare? I could angle them slightly if needed?
- 1800 W range: (maybe) Anker SOLIX C1000 for $800 with 1 panel. It also says 2400 W so idk what it is really. Can't determine the width of the solar panel.
- 1000 W range: EF ECOFlow River 2 for $700 with 1 panel. I am also not sure how big the panel is.
- 600 W range: SinKeu Portable Power Station for $230 with 1 panel.
- 300 W range: Marbero Solar Generator for $230 with 1 panel.
I'm discovering that these companies never specify the dimensions of the solar panels because they assume no one would ever use them indoors. Probably for good reason. If they don't fit horizontally, I guess I could stand them up lengthwise.
I'm sure it would be possible to find a cheaper solar panel separate from the power bank. But as a ballpark, those are my initial numbers.
Math
Imagine I spend $2500 on the 2200 W Jackery model, with 2 panels. I could put them in the two bright west-facing windows. Let's just pretend they can get their maximum output and that charging time isn't an issue.
Let's say I use this every time I run my oven, dryer, washer, or dishwasher (not at the same time), and otherwise I connect it to my fridge and most other electronics. (I know I said my oven could be 2500 W, but I usually just use one burner, and I bet that's more like 1500 W.) Let's pretend the hassle of running all those cables has been solved somehow.
I really don't know exactly what my electricity breakdown is. If I have the heat/AC mostly off and am not in the unit a whole lot (e.g. traveling for some of the month), that's when I end up with a $75/mo bill. But if I'm out of the unit, that means I'm also not using my dryer/washer and other devices as much. I guess the fridge was still on. The $350 side of things is because it's hot and I'm running the AC more, and maybe slightly higher dryer usage for some laundry-related reason. So maybe I'll say the minimum I'm spending on non-heat/AC electricity per month is $50-100, and at most maybe something like $150.
So in this super optimistic scenario, the portion of my monthly electricity bill I suspect I'd be able to theoretically save would be $50-150. Let's just say $100. That means it would take 25 months to pay back if all goes well. Honestly that's not so bad.
If I instead bought the 1000 W ECOFlow setup for $700, I could cover all my non-intensive electrical uses. The main beneficiary would be the refrigerator, the computer, and maybe the television. I think the savings there would be like $25-50/mo at most, being pretty generous. If I say $35, that would be about a 20-month payoff. That's also pretty good, but if it'll take about the same amount of time to pay for itself, I'd rather get the higher-wattage one.
Numerous caveats:
- It's not always sunny in Philadelphia.
- The panels will not be at 100% efficiency because the window is cloaked in shadow half the day, and there is no way I get the angle perfect, and maybe the glass affects how much energy they can absorb or something (would it help? hurt?). This isn't inherently an issue, except...
- ...that the charging time for the power station might be long. Some of the reviews say 6 hours in maximum sunlight, so for my use-case there's no way it would be faster than 12 hours for a full charge, and probably more. I use my appliances kind of a lot. The fridge is always running, and either the washer, dryer, oven, or dishwasher are running a pretty good chunk of the time. I think that I could get by with this... but I probably wouldn't be able to use it as much as I'd like (there are often moments where more than one is running simultaneously), so...
- ...the payoff time wouldn't actually be 25 months. I suspect there are some factors I'm not thinking about that would reduce the realistic amount of energy I'd save here. Let's say it is half as effective in my setup as a normal person's, because the sun is half as visible or something, and the charging time is too slow to use often, or whatever. At a 50-month payoff (4 years), I would start to get skeptical. But not inherently opposed.
- I use my windowsill for other things that like sunlight, like plants. I would have to move the plants that really love the sun somewhere slightly dimmer. Is it worth it???????
- I also like to look out my window, and if I had a huge solar panel there (especially if I had to stand it up vertically for space reasons), that would be a bummer perhaps.
- Constantly charging and discharging this thing probably reduces its effective wattage output fast. I.D.K. by how much. But there might be a point where I can't use it for my high-wattage devices, which would largely defeat the purpose of buying an expensive model. Not clear to me what the timeline for that would be.
- I still can't figure out if the panels would actually fit in my windowsill.
- Since it wouldn't be able to run more than one energy-intensive device simultaneously, I'd have to be careful not to keep it plugged in to too much stuff at once. It would overall be a bit of a hassle to plug in the panels and the charger and everything. Maybe the panels could stay plugged in, but even so.
- Running extension cords all over the house and putting a giant solar panel in even just one or two of the windows would result in a catastrophic domestic state of affairs. I can just imagine the eye-popping that would happen if I set that up unilaterally.
Takeaway
There is almost definitely something I am not considering. My math is so napkin-based, so imaginary and so optimistic.
But even if the practical efficiency isn't great, I feel like this could maybe possibly actually work, and could save me a bit of money. I would just have to spend it all up front. I mean I don't have $2500 on hand. But I could scrounge up part of it and put the rest on credit. And it would make for living room conversation with guests?
Realistically this seems like an amusing but too-annoying to actually do sort of project. If you know anyone who's done something silly like this and had it work, let me know! I'd be curious what their experience was.