Our Solar Panels

A reader asked if I would write a blog post about our solar panels. I honestly don’t know a lot of the technical details about them but I will share what I do know and if anyone has any technical type questions, I can get answers from Vince.

As some of you may know, we installed solar panels at our house in Texas. The house in MO already had the solar panels installed.

It looks like the new Inflation Reduction Act is restoring residential tax credit back to 30%. You’ll have to do your own research and see if that’s actually what it’s saying. This is the article Vince sent me.

Location:

The first consideration should probably be whether you have a location that will give you optimum benefits from the solar panels. Ideally, they should face south. Do you have room for a ground mount? Do you have room on your roof for a whole system facing south? Do you want them on your roof? We see some crazy configurations on roofs around here. Houses that have multiple cuts and fancy roofs don’t allow much room for a large solar system facing south. If the area of the yard where panels would have to be placed in order to have south facing panels is blocked by shade trees or a neighbor’s house, that’s an issue.

In Texas, as I mentioned, our panels were on top of a two story shop building with a metal roof. There was no way either of us would go up there to wash those panels or even check on anything (that would be Vince because I wouldn’t have a clue what to check for). Here, the panels are ground mounted and on the side of the house where they aren’t “in your face”.

I don’t think we would ever put them on a roof again. But, I don’t think we’d ever be moving again.

Power Buy Back:

Some people put the solar panels in to be green but if the finances matter and you would like to recoup your investment, the first thing you need to do is find out how your electric provider handles power being returned to the grid. Some companies will say “thank you” (or not) but will not pay for it. In Texas, we were deregulated so we could choose our retail provider. We signed a contract that was anywhere from 1 – 3 years. Some years, depending on how hard green energy was being pushed, the deals were better for us. I think the last contract we had was that we paid 13 cents for power and they paid us back 13 cents for what we sent back so if we used 1500 kwh, our bill would be $195 (plus the add on charges). If we sent back 1200 kwh, they gave us credit for $156. Of course, in the summer, we always used more than we sent back. In the winter, because we had gas heat, we always sent back more than we used. Say we used 600 kwh, our bill would be $78, but then we sent back 1,400 kwh, we got a credit for $182 and ended up with a credit balance of $104. The credits were kept in our account and on our anniversary date, if we had credits, they sent us a check. We never did because in the summer, we used up the credits.

Here in MO, I think we’re again paying .13 per kwh and getting back .02 for what we send back but it’s calculated differently. Say we use the 1500 kwh, and our bill would be $195, and we send back 1200 kwh, which at .02 would be a credit of $24, making our bill $171, instead of calculating it like that, they say “You used 1,500 kwh and you sent back 1,200 kwh, so your net usage is 300 kwh at .13 cents so your bill is $39. We have electric heat and the solar panels don’t produce as much (less sun, some days they’re covered in snow) so we have yet to send back much more than we used in the winter here. We have the shop that’s air conditioned, we have too many fridges and freezers. I think our highest bill in the winter was about $120 and that was the first winter when we had so much cold and snow (three nights with the lows in the -20’s). Usually from about March through July, we don’t owe anything. The August and September bills (which are for July and August) run about $50. I think we pay less than $400 per year in electric bills.

The Installer & The Manufacturer:

You need to do your homework and make sure you’re dealing with a reputable company and a company that has some history. Ask lots of questions and if the answers don’t seem quite right, they probably aren’t. When we started looking, we talked to five or six companies. Several were ruled out after the first serious conversation. In the end, we liked the people at one company better but the prices was so much better at the company we went with and they had been in business for years and had good ratings. We were very happy with them.

Sizing the System:

It’s been 8 or 9 years since we had the system installed in Texas so things may have changed. All of the companies we dealt with wanted to know the cost we were paying for kwh, how many kwh we used per month on average. That way they were able to determine what size system we needed and they were able to give us an almost exact amount of time it would take for us to recoup the investment.

Grid Tied System:

We have a “grid tied system” which means we’re tied to the grid. If the power goes out for 10 minutes, 10 days, 10 months . . we have no power.

Batteries:

The only way to get away from being grid tied is to have batteries. Vince feels like it just isn’t worth it. Battery technology/longevity is improving. Vince was telling me yesterday that the new Green Energy Deal (or whatever it’s called) will (or has) restored tax credit for installing solar panels and includes batteries. There are systems where you can have some batteries, not necessarily for the whole house, and have it set up to “trick” your system into thinking it’s running on the grid when in reality, the grid is down and your panels are powering your house or whatever portion of your house you have hooked up. This all has to be set up very carefully and approved by the electric company because this can cause safety hazards if the power is being fed back into the lines.

Reliability:

We’ve had almost zero problems with them. There’s some kind of box that sends the info to our account so we can see how much power is producing, we could see what every panel was doing in Texas because we had micro inverters. That box had a problem not long after the installation and was replaced under the warranty. Other than that, we had no problems (that I recall) in Texas. Here, the system may be a few years older or newer . . I don’t even know when it was installed. We’ve had no problems with it.

Return on Investment:

This is going to vary with everyone based on how much power you use and the cost of the system. I have no idea how much it would cost to add a system these days. The companies giving estimates should give you all that ROI info based on costs mentioned above. At this site, you can put in some info and it will tell you how many solar radiation would be produced on average based on your zip code.

Here’s the info, based on an 11 kW system at our location in Texas:

Here’s the info – same size system, at our MO location:

I’m not sure if this takes into consideration the efficiency lost on days when the temps are upper 90’s to 100’s in Texas or if it accounts for solar panels in MO being covered in snow and ice for a few weeks in the winter. I’m sure there are ways to clean the snow and ice of (either heaters or blowers) but for us, it isn’t that much of an issue.

As far as ROI, so much of it is how you look at it. I have no idea how much a system like ours would cost today, after whatever rebates may be available. I’m going out on a limb and saying $20,000. On average, we save about $300 per month on the electric bill. $300 x 12 = $3,600. Then, $20K divided by $3,600 and it would be about a 6 year pay back time. If we saved $200 per month on our electric bill, that would make it about an 8 year pay back time.

Interesting Info:

The heat affects the efficiency of solar panels. I have read that for each degree over 77, the panels lose 1% efficiency. I think it’s different on different panels but the spec sheet you receive for any proposal should list this info. In Texas, our panels were on a metal roof that was two stories tall so I’m thinking we lost a lot of efficiency in the summer but that is all factored in when the company is calculating the size of your system.

Also, we had hail in Texas that broken some windows and didn’t damage any of our solar panels. That surprised me.

I think that’s about all I know about solar panels. There is so much info on the internet. Research as much as you can and, again, if you have specific questions, Vince might can answer them.