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Comment by NewJazz | Hacker News Reader

Also how much are we saving flipping lights off for a few hours in the age of LEDs? Most of my electricity bill is either fixed costs or from heating water.

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I recently installed a basic flat, round, white LED overhead ceiling light in a bedroom that's been repurposed as a home office (replacing a very old dual screw-bulb center of ceiling fixture on the octagon box), and I don't know if there's any actual savings in the new unit. The previous thing had two "same size/shape as an incandescent" 11 or 12 watt white LED "bulbs" in it, the new unit is specced at 28W. It provides a more evenly distributed light and has a toggle switch to choose between three different color temperatures.

At $0.11 per kWh if say it's 30W and I leave it on 24x7 for a month it's 22.32 kWh, or about $2.5 of electricity a month. Multiply by three for like $7.5 a month if this was a California electric rate. In the longer run I'd like to have a way to turn it on and off automatically not so much to save money, but to have a way to turn off all the house lights in one toggle in home assistant when going to bed, just for the convenience of it.

Across my house, I think I have about a kilowatt or two of LED lights, mostly in the form of ceiling cans at 16W each. Running everything full brightness would thus be about $0.30-$0.50 per hour. It’s the paradox that the same rooms probably would have used the wattage with the old incandescents, it just would have had a lot more shadowy corners.

Do you grow any plants in your home? An average family home will have around a tenth of that energy consumption if you turn on all the lights. 200 watt tops. That is 25 LED bulbs of 8 watt.

Yeah even at 16W per bulb that's over 60 bulbs. Either a big house or a very very bright one.

Yes almost 60 sounds right, and I keep the dimmers at about 50% usually since it’s a small condo. But it also very /evenly/ illuminated. The builders chose this, not me. Your typical incandescent hallway or stairwell probably used to have 1-2 lights (60-120W) to cast enough light to get around. Now that same hall in modern LED style might have 4-6, because it eliminates shadows, not because it makes it brighter in a given spot. Same for the kitchen—it probably used to have one central 100W light and 50W over sink, and now a modern style build in the same space might have at least 6 LED ceiling lights+6 under cabinet lights

How small? Under 900sqft? I've got 70W (20x 3.5W) in ny living room and it is quite bright at 100%, I usually dim to around 20-50%.

About 1700sf with taller than normal ceilings. It’s unnecessary bright in the evening, but blends with sunlight in the day. I feel like our brains must interpret light differently depending on the angle it reaches the eye. I used to rent a place that was 900sf with normal ceilings, which had 4 of those tiny sort of ones in the living room, and it was painfully bright in the way they concentrated the light into spots so we never used them (unfortunately they didn’t have dimmers)

I realized I did accidentally almost double my final number, so 500-1000W would be more accurate for the way this condo was built (depending on which extra lamps we are including—does every understair closet light count or just the main rooms, at the low end estimate)

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