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Does that use a lot of energy?

hannahritchie.github.io

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Re: Does that use a lot of energy?

#171

Post by frankus »

lokar wrote: post #145
frankus wrote: post #125

Earlier quoted context omitted.

The electric shower also seemed pretty optimistic. I live in an area with about 50°F/10°C ground temperature and my 14.4 kW water heater can just keep a relatively efficient shower head flowing at a comfortable temperature.

Heat pump or resistive?

This one is resistive (tiny and cheap to purchase) but will be just an emergency-backup shower once my home renovations are done.

The house is getting a split-system air-to-water heat pump with an indirect tank for domestic hot water, so it should cut that down substantially (the unit maxes out at around 3kW input but likely will run longer to recover/preheat).

Re: Does that use a lot of energy?

#172

Post by ssl-3 »

frankus wrote: post #125
ssl-3 wrote: post #66

The presentation is nice, but some of the conversions are questionable. For instance: The cost section, wherein 1kWh in the US is figured as having a cost of 9.7 cents. In reality, it's not that way at all. Unless we're fortunate enough to live in an area where we can walk over to the neighborhood generating station and carry home buckets of freshly-baked electricity to use at home, then we must also pay for delivery…

The electric shower also seemed pretty optimistic. I live in an area with about 50°F/10°C ground temperature and my 14.4 kW water heater can just keep a relatively efficient shower head flowing at a comfortable temperature.

I had this problem once with a water heater: Get in shower, and things are nice and hot. But the temperature decreased rapidly, and immediately.

It turned out that it had been plumbed backwards.

Re: Does that use a lot of energy?

#173

Post by megaman821 »

quickthrowman wrote: post #116
erelong wrote: post #109

not sure I understand the petrol car using 3x as much energy as an EV... wouldn't it make sense to convert gasoline to electricity then? I presume that must not be as efficient as other ways to convert fuel to gasoline? (I understand the math is there but... I'm temporarily failing to get it) I think lists like these might be useful for energy audits and thinking about ways to make better use of energy

Gasoline engines are around 30-35% efficient, the rest is lost as heat. That goes for whether they’re spinning an alternator as part of an engine-generator set or just moving a vehicle. You can’t get more than 35-40% efficiency so converting to electricity is a wash, you lose the energy to heat no matter what. Also, the chart does not take into account how the electricity for the EV is generated, it would be just as…

To get those types of numbers you would have to be charging from a grid that is nearly 100% coal. Real grids heavily favor EVs.

Re: Does that use a lot of energy?

#176

Post by no-name-here »

oulipo2 wrote: post #18
bena wrote: post #3

My first question was: "Is this whitewashing LLM energy usage?" And yes, that seems to be the undercurrent here. Complete with linking to themselves to validate the data they used to make their estimates. Either these companies need to build these massive data centers that consume massive amounts of electricity OR these LLMs don't use a lot of electricity. You don't get both. If LLMs don't require a lot of electricit…

Indeed, looking at a "single median query" totally disregard the fact that: - first, those queries are mostly useless and we could totally do without them, so it's still a net pollution - they are being integrated everywhere, so soon enough, just browsing the web for a few hours is going to general 100k+ such equivalent "small queries" (in the background, by the processes analyzing what the user is doing, or summariz…

1. Your prediction is that soon browing the web for a few hours is going use >30,000+ Wh (based on the "equivalent" you mentioned)? (For comparison to that 30,000+ figure, the energy use from using a laptop for a few hours is 75 Wh, all per OP source.)

2. > most of this will be done just to sell more ads

Are you predicting that the value of ads is going to increase by a number of magnitudes? Because 30,000+ Wh of electricity has a quite significant cost, and even a video ad currently only earns pennies, so I'm trying to imagine how the math would work in this scenario?

Re: Does that use a lot of energy?

#177

Post by Hamuko »

jolmg wrote: post #63

> Desktop computer - 1 hour of use - 50 Wh That seems low...

Thought the same thing. I think I measured my gaming PC to idle at like 70–100 watts. Obviously an average office PC would be lower, but you also need to add on the energy for the monitor, which seems to start at around 15 watts for some basic monitors, and I imagine that's not at high brightness.

Re: Does that use a lot of energy?

#178

Post by antisthenes »

frankus wrote: post #170
OldSchool wrote: post #148

Earlier quoted context omitted.

IF the joules of energy in your EV battery came from gas-fired or coal-powered generation, a similar amount (~60%) was simply dumped somewhere else.

I wish we did more e.g. district heating with that waste heat in the US.

That means relatively dirty combustion near where people live. The population density around fossil fuel power plants tends to be pretty low in wealthy countries.

You can't pump hot water the same distance you can transmit electricity on HVDC towers.

Re: Does that use a lot of energy?

#180

Post by MostlyStable »

quickthrowman wrote: post #112
MostlyStable wrote: post #80

Earlier quoted context omitted.

I turn LED lights off because of the difference in operational life, and I don't like changing bulbs. M GE bulbs say they have a rated lifetime of 13 years......at 3 hours of usage per day. So if they don't get turned off, then that 3 hours can very easily become 12, and now you are at a rated lifetime of ~4 years instead.

A ‘standard’ (A19 shape, E26 base) 8W 800 lumen LED lamp costs around $5 and will use about $20 of energy over a 15,000 hour lifespan, assuming $0.15/kWh. That works out to around $0.035 per day for the lifespan of the lamp if you run it constantly for 24 hours a day, I wouldn’t waste time thinking about it. It’s an extra $10 over 12 years, you’re still using the energy. Investing in occupancy or vacancy sensor wall…

It's not a cost thing, I just don't like changing bulbs. I find it annoying, and with enough bulbs, when the lifetime is down to 4 years, you are doing one every few months on average.

But yes, I have thought about presence sensors. I'd really only need 3-4 to cover the primary areas where lights get turned on and not off (if I don't do it). I just haven't gotten around to it

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