Information on solar panels- a whole lot of information

 

Hi. I didn’t think solar panels would work for my house because of trees. But then my neighbor got them and I started talking to him about solar. He’s an electrical engineer for a utility so I figured he knew what he was doing. This was in the spring of 2022.

I live in Westchester County, just north of NYC. Electricity was around 25 cents per kilowatt hour at the time (that includes both supply and delivery charges).

I got six bids. Here’s roughly how the process works:
One company insisted on coming to my house- that was really just for the hard sell as they didn’t need to see the roof. And they were 50% more expensive than everybody else. FYI this was the company that approached me as I was leaving Costco.

The other companies use google earth to see your roof and trees and estimate how many panels fit and how much they would produce (which depends on the pitch of your roof, which way it faces, and trees, which they can sort of see on google earth).

They send a rough proposal and if you’re interested then you pay a deposit and they come and measure. Then they give a revised proposal which I guess you can reject if for some reason you want to, like it significantly differs from their estimate.

Some companies will negotiate price. Or at least they did that summer. Since the tax credit went from 26% to 30% and power costs have gone up it’s possible they’re busier and less flexible.
And now, with the tax credits going away after 2025 the solar companies may get really busy and not budge on cost.

They size your system based on your past 12 months energy use. You can give them access to your utility account or you can just look at how many kilowatt hours you used every month (it’s right there on your bills, which you can find online).

Before contacting companies, feel free to email me. I’m upfront about this- two of them will give me a small referral fee.

If I’m not too busy I’m happy to look over proposals. I’m not an engineer but I did learn a ton about solar. There is one thing that nobody tells you- so if you’re interested, keep reading. I’ve helped several people in my town go over proposals and I taught them which questions to ask.

They initially told me something like 16 360 watt panels on the back of my house would cover my energy usage. I said as long as you’re doing the work, why not fill the whole back of the roof? That ended up being 22 365 watt panels. I figure my next car will be electric, I may get an electric induction range (which I did, and I love it) and when my gas dryer dies why not go electric?
You’re not supposed to get panels that will produce more than 110% of your usage (at least not in NY) but as soon as I said ‘electric car’ that was no longer an issue.

I asked why the company makes 360, 365 and 370 watt panels (they’re all the same size) and why not install the 370s? They said actually it’s the same panel, but since every panel is a little different the manufacturer tests them and labels them accordingly. And they said the reason they’re offering the 365s is that they bought a ton of them because that was the most cost-effective.

With my solar panels I’m producing more electricity than I use. That excess goes to Con Ed and I get a credit for it. Not dollars, but in kilowatt hours. So the excess I produced got me through the winter- I don’t produce as much as I use in December, January and February. And then in the spring, summer and fall I’ll have a big surplus. Even though I now have an electric car I still don’t pay for electricity (except for a $35/month connection charge). Note- this is NY-specific. How your local utility deals with excess production may differ. Some states buy your electricity cheap when you over-produce, and then sell you expensive electricity when you need it.

Billing is done on a per-month basis. My first month’s bill was lower than usual (panels were installed about a week before the end of the billing cycle). Then my second month showed that I produced 350 kwh more than I used. Essentially the meter runs backwards.

One thing- the rated power of a panel is based on certain conditions which are rarely met. So my 365 watt panels will mostly produce less, although they may occasionally produce more.

The panels will NOT power your house during a power failure. That’s by law, because they’re connected to the grid and the utility doesn’t want your panels putting electricity out to the street when they’re working on broken lines- someone could get electrocuted. There are work-arounds. A piece of equipment that’s several thousand dollars (and available with only some types of systems), or battery back-up. 10 kwh of battery back-up (that’s enough to power most stuff in my house other than air conditioning) was around $15,000 before tax credits and I didn’t think it was worth it. We’ve been lucky here- rarely any power failures.

Note that in a few years most electric cars will be probably able to power your house in a power failure- and a typical electric car battery is around 80 kwh which is several days of electricity use. A few EVs already do this, but not mine.

Here’s the economics of my system, and then something to watch out for that nobody tells you about.
Cost (summer 2022- prices have increased a decent amount since then):
$23,614
less: 30% federal tax credit (it’s a credit, not a deduction, so you get that much back on your taxes): $7084
less 25% NY State tax credit (capped at $5000): $5000
less the savings from paying with a 2% back credit card: $472 (this is great because it’s more like 4% back on the net cost after tax credits)
Actual cost: $11,058

But I’m actually doing better than that. Because I have an electric car, my utility gives me back 10c/kwh for charging my car at night. Yes, even though I’m not paying for electricity, I get a rebate for charging my car after midnight. So far, in less than two years, that’s added up to almost $1000. And I drive only about 10,000 miles a year (and my car is one of the most efficient EVs).

Here’s the thing nobody tells you about solar panels:

When they quote the size of your system, it’s the capacity of the panels, not the inverters.
Your system is the solar panels, inverters (to convert the solar panel DC output to AC), a controller and some wiring. (FYI you want a microinverter for each panel- not one big inverter for the whole system- those are old-fashioned and not very efficient)

They size the panels bigger than the inverters. They say that since my 365 watt panels will rarely produce 365 watts it’s not cost-effective to use 365 watt inverters. So there will be some clipping (wasted production) but it wasn’t worth sizing up the inverters.

But they didn’t give me that option or a proposal to reflect that. I think that for competitive reasons they just want to quote the lowest price they can.

That said, the experts agree with them. I don’t, and here’s why:

They told me my system is an 8 kw system (22 X 365). But the capacity of my inverters is only 6 kw. I wish they had also estimated production with higher-capacity inverters and I could’ve made an informed choice. But no company did that. So I would recommend asking that question.
To go from 290 watts to 325 watts would have been about $20 per inverter (or $440 for my system, before tax benefits). I think I would have spent the money, but I guess for competitive reasons nobody wants to quote a higher price than their competitors.

At the time they said it would take 2-3 months from contract to going live. Part of that is their budgeting time for the building inspector to approve the project. Some are faster than others, and you may also have to wait for the power company to do their inspection.

The inverters I have are from a company called Enphase. They’re nice because there’s an app that shows me production and consumption every 15 minutes (or real-time if you click on that). So I can see how much I produce and use at 15 minute intervals. This is interesting but it can become an obsession.

The panels I have are from REC. They seem highly-rated. Panel production declines over time but they say it’s 0.25% per year. So in 25 years they’ll be producing 92% of new. I don’t know how accurate that is because the panels haven’t been around very long. But it is better than some other companies’ claims.

One thing I noticed- I have an attic fan. Since I got the panels it goes on much less. Because with the panels blocking the sun, my attic stays cooler. Which is good for the air conditioning system (and reduces electricity use for the A/C and the fan).

Oh, not a good idea to put solar panels up if your roof will need replacing any time soon. It might make sense to just get the new roof now, rather than waiting until the roof needs replacement.

And- there’s something called squirrel guard or critter guard. It’s fencing around the panels so animals can’t chew on the wires. I’m not sure that it’s economically justified (chances are low) but it’s peace of mind. You don’t want to have to deal with replacing stuff and having no solar production if you don’t have to. I’m a big believer in not buying insurance for risks you can afford, or for taking dumb gambles, but I got these because I wanted to avoid future headaches.

If you might be selling your house in a few years it may still be worth going solar. Zillow, for what that’s worth, says that houses with solar panels sell for something like $16,000 more than houses without it. It is a cute selling point that the buyer will never have to pay for electricity, if your system is big enough. But then there are some people with really big systems, but they live in AZ and use a LOT of electricity for air conditioning.

You have four options with solar:
1. Buy the system for cash (this is what I did).
2. Finance it with either the solar company or somebody else (home equity loan, etc.).
3. Lease the system- THIS IS A BAD IDEA. The end-of-lease options aren’t usually nice, and if you sell the house and the new owner doesn’t want to take over the lease, then you’re going to have a major headache. Even if the new owner wants to take over the lease it’s just more work to deal with it all.
4. They own the system and sell you the electricity under a power purchase agreement- THIS IS ALSO A BAD IDEA.

Two companies I recommend (please mention my name: Shaun Breidbart, and let me know)
David Kowalsky for systems in NY: DavidK@gopowersolutions.com 347-201-5723
(for systems OUTSIDE of NY use davidsolarguide@gmail.com) 347-201-5723
James Stewart jstewart@kasselmansolar.com (NY only) 845-214-7946

One more thing- if you’re thinking about doing it, sooner is better than later. No reason to wait. If you’re waiting until you need a new roof, you might as well replace the roof now. You’re not going to be in the house in thirty or forty years when that roof wears out. And in the meantime you’re paying for electricity that could be free.

(FYI in July 2023 I bought an electric car, and in February 2024 my gas dryer broke and I replaced it with an electric dryer; I also bought an induction range that I LOVE. And I still produce more electricity than I use, so probably next winter I’ll use some space heaters around the house, just to use up some of the free electricity.)

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