Thursday, May 27, 2021

Powerful news

I have some “powerful” news: I got* my first electric bill that includes an entire month of solar power generation. The tl;dr version is this: I’m very happy with the results so far.

My power bill this month is 44% of what it was last month—or, if you prefer, I saved more than half over what I paid last month. During this same time, I received a total credit of $44 for the electricity I sold back to the power grid. Even if you take that out of the equation, this month I'd have paid 65% of what I paid last month (or, I saved 35% this month). The credit I get for generating electricity clearly expands my savings.

What this shows is that during the daytime I’m usually self-sufficient in electricity. On dark, rainy days, I generate less power and probably use it all, as well as possibly buying some power. However, on sunny days, and even bright cloudy days, I produce more than I can use. At night, the power I use all comes from the grid, of course.

The power meter was read for this bill only a couple days after the installation of the device to prioritise hot water heating by solar-power (something I talked about last week), so next month should be a truer indication of how things will go over the winter months. After that, it'll just be ongoing savings, whatever they are.

To make sure I compare apples to apples, I’m going to set up a spreadsheet to chart the costs/savings per kilowatt hour to more precisely calculate savings than using tax-inclusive totals does (though I’ll track that, too, in part because it’s simpler to tell people). This will also allow me to compare my new costs to what I paid last year. (I mean, of course I’m going to do that…)

Even though I expect to see further savings next month, I’m still very happy to have cut my power bill in half (more than in half, actually…), as well as the fact I’m sending electricity out to the grid—those were always my only goals. However, at the moment it looks like it will take about a decade for the system to pay for itself, which means that my savings in what I pay for power will equal what the system cost me. That’s about what I’d expect. However, this isn’t a perfect calculation: Retail electricity prices will only rise over time, and if this was a business venture, the solar system itself would depreciate. So, the system will probably “pay for itself” faster than simple arithmetic might suggest. I’ll track that, too, just as I did with my lawnmower.

As it happens, though, rising property prices have already “paid” for the system: If I sold my house right now, the amount I’d get for it (compared with what I paid for it) would more than pay for the system—and all the other improvements I’ve made, for that matter. To me, though, all of that’s a nice bonus, and not important.

I’m just happy that I got exactly what I wanted and expected.

*I got the bill online because I hadn’t received it by email and I was impatient. The bill had “COPY ONLY” on it. I later got the bill by email and it was identical, except without the words “copy only”. I have absolutely no idea why they do that—maybe the one they email me is the NFT version? (that's a joke, just so I can use "NFT" in a sentence, since I may never blog about it).

This is a somewhat expanded version of something I posted on my personal Facebook a couple days ago.