Probably. We did some maths to justify the switch, and it can actually be cheaper too.
What you’re paying for though, is convenience. You don’t need to be near the mains. Battery powered lights will last about a week if used for 6 hours a day. Electric lights will cost a few pence per day (assuming 6 hours of use again). This is per set of lights of course.
So if you’re buying new batteries the costs will add up.
I already have a large collection of Eneloop batteries that I’ve needed less and less as more things have started to come with the own internal batteries that charge with USB C.
To recharge these Eneloop batteries, it’s about 0.8p to recharge two batteries fully. So 6 batteries will cost 2.4p per recharge, which is enough for 100 hours of lights. It will cost 17.5p to use electric powered lights for the same length of time. So for us, it’s 15p cheaper per hundred hours of light time per set of lights. Calculations are based on a standard string of 200 LEDs.
This ultimately of course still winds up drawing electricity, but much less of it. I’m not an electrician so couldn’t explain how it works, but it’s cheaper to recharge batteries to provide 50 hours worth of light than it is to run the mains powered equivalent for the same duration. It’s not just a theoretical math equation either, we’ve been monitoring it since the they went up this week. The batteries indeed costed less than 1p to fully charge two of them from empty. The mains powered ones are costing more than 1p per day (timed to switch off after 6 hours). Both are LED strings of 200 fairy lights. 16 meters long. 8W (80 halogen equivalent).
For outdoor lights, you could consider solar powered ones too and operate them entirely off grid. We should still get enough sun in a winter U.K. to keep the battery fully charged (again assuming 6 hours of use). We’re way up in the north of the Scottish highlands and island and have had no troubles keeping our outdoor solar powered ones on at night. Again, they come on at dusk, and are timed to switch off after 6 hours. Costs nothing in batteries or electrify because solar is free. Higher up front cost for the lights though. The batteries it recharges though, are just rechargeable AA, so if the sun were to fall into a black hole tomorrow, you can always charge them yourself. But we’ve not had to do that yet, and we don’t get much daylight or sun at all at this time of the year.
Standard disposable alkalines will of course cost a lot more to run, but at least you’re not pulling unnecessarily from the grid to keep the lights on. Not that the tiny minuscule of power you’d be drawing either with mains or rechargeable batteries will make a discernible difference at all. You’d have a bigger impact just turning your tv off for an extra hour a day. Or boiling the kettle one less time. Or turning the heating down. Or spending 30 seconds less in the shower. All of which is to say, don’t worry about it. And if you are worried, there are other things you can do to make a bigger difference with negligible impact on your life than not putting the decorations up.
