Hacker News Reader

> Maybe it’s because I grew up with incandescent bulbs

It is soooo that. When I bought my house 8 years ago I immediately had to replace some incandescent bulbs that shared a circuit with the microwave because the power consumption was tripping the breaker. And then I had to do the math to figure out when it was cost-effective to replace everything with LEDs. So I've become extremely cognizant of what things consume, and exactly what that costs...

Now I've got everything automated with LEDs and presence detection and schedules to turn things off when people aren't around or shouldn't be awake. Yet, lights needlessly being left on still bothers me.

> In the early 70's.

There were less lights in poor homes. The more affluent homes had suspended lights with multiple bulbs. (I am not sure how it is called in English). I recall that a lot of homes got more light bulbs and ornaments through the century, as they become more affordable and more hype.

The increase in count came with a decrease in power. The typical 100-150W bulb got replaced by multiple 30-50W bulbs, they do not consume significantly more in aggregate.

> The more affluent homes had suspended lights with multiple bulbs.

I think these are called chandeliers. The etymology of chandelier is French.

> Every light in our house is LED and I still teach my kids about not wasting energy and turning things off when not in use.

Are you certain that it's wasting energy, though? You have to account for the time spent actually turning the light off, as well as for the psychic cost of having to think about whether to turn it off or on.

I'm reminded of one of my old offices, where some office busybody turned off the lights in the bathroom. They were fluorescent and took awhile to brighten up, so of course this meant that one would enter a darkened room, turn them on, and then slowly get some light. Was it a huge deal? No. Did it make our lives worse than just leaving the lights on? Yes.

> Maybe it’s because I grew up with incandescent bulbs, but I can’t stand the thought of random lights being left on for no good reason, even if it costs 40 cents a year to keep lit.

At 40¢/year, leaving it lit costs .11¢/day, or .0046¢/hour. At any reasonable rate for your time & mental energy, it makes sense to just leave it lit.

> They were fluorescent and took awhile to brighten up, so of course this meant that one would enter a darkened room, turn them on, and then slowly get some light. Was it a huge deal? No. Did it make our lives worse than just leaving the lights on? Yes.

LEDs don't do this. At absolute worst, you'll have a fraction of a second before they light up at all, but once they light up, they light up immediately.

LEDs also work much better outdoors at low temperature.