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I have been playing around with solar power, buying two 425-watt panels and a power station that can store 2 kilowatt-hours of power. However the power station is limited to 500 watts of input, so I am often wasting power. It is still helpful to have both panels if I want to have any chance of filling the power station in a day. The power station was $600, the same price as both panels, so it would be nice if you didn’t have to buy your own storage. Plug-in solar is a way of feeding solar power directly into your house through a standard electrical outlet. Because a 15-amp household electrical circuit can only carry 1800 watts, the system has to be sort of small, often capped at 1200 watts. A plug-in solar setup has a solar panel, an inverter to convert DC solar power into AC, and a plug. Utilities don’t like it because if your power line is severed, the end coming from your house will be electrified. If the line is severed past the local transformer, your 120 volt could be multiplied substantially. Newer and better inverters monitor the household power and if they sense a blackout, they immediately cut power, so this is something that has been solved. Accordingly a few states have made this legal.

The idea is that you can offset your baseline usage with solar, but the problem is, what is your baseline usage? During the day, when there is plenty of sunlight, I might have a couple of lights (with LED bulbs) and an internet router and server, but everything else is on demand, like if I use a computer or watch TV, which isn’t all the time. Nor is the compressor on the refrigerator running all the time or the air conditioning. So my baseline could easily be less than 100 watts. My two panels can produce 850 watts at best, but it isn’t often that my house is using that much power.

So the question is what happens to that power if I don’t use it? In some places, it can go back out to the grid and maybe you even earn credits for every kilowatt-hour you supply to the grid. But the power company would rather pay you their production cost for power you provide than give you full retail price. I think in Georgia the power typically doesn’t go anywhere, so it is just never used at all unless you have everything professionally installed, inspected by Georgia Power with maybe a new meter that you have to buy, pay fees, and then you can start getting paid a fraction of what you pay for power. Even some payment is better than nothing and at least the power would get used, meaning Georgia Power burns less natural gas.

Another issue with plug-in solar that is technical enough that a lot of people don’t talk about it, has to do with the nature of your 120V power circuits. If you want to dump power into the circuit, the power can power anything on that circuit, but it can also go back to the breaker box and power everything else in the house that uses that hot wire. The problem is that generally houses have two hot wires, so you are only providing power to one of them. The other half of your circuits are using a different hot wire so they are powered only by Georgia Power. 240V circuits use both hot wires, so your dryer, electric stove, and HVAC will get half of their power from the hot wire that you are dumping power into. Another problem is it is kind of hard to tell which outlets are using which hot wire, but if you want to make sure you are making the best use of your plug-in solar power, you need to know. You can go the breaker box and figure it out, but I have a fuse box subpanel and I don’t know how that breakdown works with its four circuits. There is a device that can help tell you by figuring out the difference in the signal timing, but I don’t have one of those. Even if you know, maybe some of the things that you power are on the wrong hot wire. I think there are inverters that can go to a 240V circuit and therby power both of the hot wires. Maybe even one that has output for both and would possible plug into two different outlets?

A neat aspect of using a plug-in system would be that I could plug one of my panels into my battery directly and also draw power from a wall outlet which could get power from the other panel using the plug-in inverter. The Aferiy is capable of charging itself from two sources like that. With the battery I can set how many watts it is drawing from the outlet, but as clouds go by or shadows fall on the panel, I can’t guarantee that all of that will be coming from solar. That could work during peak hours when there is consistent sun, but I don’t think it is a great solution.

There is also a type of inverter called a hybrid inverter which can send solar power to either a battery or to my home grid or both. That could be a way of utilizing the full 850 watts I sometimes collect without wasting it.

The other option would be to have gotten a battery that can accept more than 500 watts, but that ship has sailed. I don’t think the Aferiy was a bad choice and there are other models out there that accept even less and plenty that have less than the 2 kWh storage of the Aferiy.

I was looking around on Amazon at solar generators and saw a EBL Acc2400 solar power station for $500. It has 1840 Wh of storage, which is a little less than the Aferiy, but it allows up to 800 watts of solar charging (vs. 500). It’s not like I need another one, but it seemed like a good alternative that I should know about. It looks lower quality than the Aferiy, bigger and heavier with a more basic screen and no control via an app, but it has the same battery type (LiFePO4), lots of ports, and adds wireless charging. Based on a couple of reviews it also has the same 20-30 watt or so idle drain, which means you waste a lot of power if you want to power something all day. Having two generators would let me connect one panel to each and get the full wattage from each of the 425 watt panels instead of capping it at a combined 500, which is what happens now.

As I searched for reviews of it I also got shopping results that said I could get one for $210 at AliExpress. That’s a third of what I paid for the Aferiy. While I don’t want to continue pouring more money into my solar system, it was such a good deal that it could easily pay for itself. Having ordered flashlights direct from China for years I knew you had to be really careful ordering from places like AliExpress. I had actually bought a flashlight at AliExpress a few years ago so I already had an account. I decided to go ahead and buy it for delivery in mid-October from China. I also found a deal at Temu, which is similar, but when I went to that page, it was actually a page for several different generators and the one that was cheap was actually a much lower capacity generator even though the whole page was all about the more expensive one.

I started wondering what the catch could be and thought about tariffs. I had been charged about 8% for “local taxes” which would fit if they were going to pay state sales tax, but Aliexpress didn’t mention any other taxes. It seems like from what I am reading that AliExpress doesn’t always charge you up front or even tell you whether or how much a tariff will be and it can add 40% to the price after you have paid and the product ships (the shipping company would charge me, not AliExpress). 40% would add another $80, getting the total price up to $300. Still a good deal compared to the one for $500 at Amazon, but not as good.

Looking at the listing again and getting more worried about this too good to be true purchase, I saw that they also had a tiny thumbnail that was clicked and if you clicked the thumbnail of the Acc2400, which, again, the entire page showed pictures and descriptions of, the price changed to $500. The icons looked pretty much identical, but they were actually selling three different models, just like Temu. I thought maybe I could wait and hope for the best, but AliExpress seems to feel like if they send you something that works, even if it isn’t what you ordered, that you should only get a partial refund or you can pay to send it back to them for a full refund (a 60 pound package sent back to China?). I looked up the specs on the lower priced generators and they aren’t something I would ever want, not even capable of dealing with the wattage that one of my solar panels produces.

I started an online chat with the seller (not actually AliExpress, since they seem to ba all about third party sellers, this one called Sun Furniture Store) and asked to confirm which model was in my order. The next morning they confirmed it was the lowest model with only 500 Wh of storage instead of 1800. Bait and switch all the way, but I think Amazon does something similar that you have to be really careful of where they sell multiple versions of a product on the same page and you have to look closely to make sure you are clicked on the product you want. At Amazon even if you change the size or color of a shirt, the price can change.

Anyway, lesson learned. Never order anything from AliExpress. I told the customer service person in the chat that the entire page and the item description of what I bought was 100% about the Acc 2400 and that I didn’t want the 500 Wh model and asked if I could cancel. I went ahead and canceled anyway via Aliexpress, but they wait for 48 hours to hear back from the seller. Later that day customer service said yes, I could cancel, but I still worried they might ship anyway. After 48 hours, Aliexpress did cancel the order and my credit card was refunded a couple of days after that.

I thought maybe I could make a dent in my home electricity usage by buying a couple of solar panels and a solar generator. A solar generator is a battery that can be charged up and has USB, AC electrical, and DC ports that you can use like a gas-powered generator. My electrical usage isn’t that high, maybe 300 kilowatt-hours per month on average, so that only comes out to 10 kWh per day. There are a number of solar generators out there that can store 2 kWh, so if I could fill one of those every day and use that power, I could save 20% of my electricity, however, the cost of 2 kWh only comes out to about 34 cents per day. Still, that’s $10 a month or $120 a year, so eventually a system could pay for itself.

Continue reading “Small Solar Power System”

While researching Georgia Power’s rates and shopping for a solar generator, I found out Georgia Power has a program called Overnight Advantage that you can sign up for which charges different amounts depending on what time of day you use power, with really low rates overnight (2.2 cents per kwh nominally as opposed to the standard rate of 8.1 cents). Then you pay higher than normal rates of 10.2 cents during waking hours 7 AM to 11 PM and then really high rates of 29.8 cents at peak 2-7 PM Monday thru Friday. This program might be good if you charge your electric car overnight. Electric cars have batteries of 50 kwh or more so you want the best discount on that that you can get. 2.2 cents makes it sound like you can fill up your car for a little over a dollar, but with fees and taxes, it would actually cost you about $4 to fill up your car. Still, really cheap, and even on a regular plan it would be only $8. However it could also work if you have a large home battery that you lets you run your house with stored power. I doubt that would work out for a 2 kwh battery, especially not in summer when AC use drives my power consumption up to 20 kwh per day. Home batteries are really expensive, like $6,000 to cover my 10 kwh daily usage and would need another one in Summer for air conditioning. I only use $800 of power a year.

However, it does kind of bring up the idea of bi-directional charging for electric cars, where you use your car as a home battery, charging it at night and then letting it power your entire house during the day. And taking it further, if you filled up your car overnight with 50 kwh at 2 cents per kwh, you could use 20 kwh from the car to run your house very cheaply all day and then sell another 20 kwh back to the utilty at the peak at a much higher price than you paid (Georgia Power does not do this, but they should). If Georgia Power is going to charge you 29.8 cents for peak power, wouldn’t they be willing to buy peak power from you for 15 cents? You could still make a good profit on what you sell back to them. If this could work on a large scale, the world would be a better place because we would burn less fuel and need fewer power plants. Using batteries, not even solar power, though obviously it works even better with solar. However, in places like California where about a third of the electricity is solar already, the disparity in peak and off peak prices isn’t as much because during the daytime they are generating a lot of solar, though it is still a demand peak so rates are maybe twice the off peak rates.

Getting free power from the sun has always been an appealing idea for me, but costs have always been high. Costs have come down a lot over the years, but it would probably still cost me $10,000 to install meaningful solar at my house and since I only use about $800 of electricity per year, that would take too long to pay off. Going off the grid is even more expensive because then you have to have a way to store the power in a battery to use at night or when demand is higher than what you are getting from the sun. Instead, for years I have paid Georgia Power a little extra to receive solar power (or, really, Renewable Energy Credits). At one time I thought I could get a small solar panel and hook it up to a car battery and then use the car battery to charge my phone or my laptop or whatever, and have a small and simple system, but a phone uses only a few cents of power per day and car batteries don’t last forever, so it seemed like that might not work either.

Continue reading “Solar Power at Home”