this post was submitted on 30 Mar 2025
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So, Alec over the Technology Connections channel made an hour long video explaining the difference with kW and kWh (obviously with other stuff around it).

I'm living in northern Europe in an old house, with pretty much only electric appliances for everything. We do have a wood stove and oven, but absolute majority of our energy consumption is electricity. Roughly 24 000 kWh per year.

And, while eveything he brings up makes absolute sense, it seems like a moot point. In here absolutely everyone knows this stuff and it's all just common knowledge. Today we went into sauna and just turned a knob to fire up the 6,5kW heaters inside the stove and doing that also triggered a contactor to disengage some of the floor heating so that the thing doesn't overload the circuit. And the old house we live in pulls 3-4kW from the grid during the winter just to keep inside nice and warm. And that's with heat pumps, we have a mini-split units both on the house and in the garage. And I also have 9kW pure electric construction heater around to provide excess heat in case the cheap minisiplit in garage freezes up and needs more heat to thaw the outside unit.

And kW and kWh are still commony used measurement if you don't use electricity. Diesel or propane heaters have labels on them on how many watts they can output right next to the fuel consumption per hour and so on. So I'm just wondering if this is really any new information for anyone.

I assume here's a lot of people from the US and other countries with gas grid (which we don't really have around here), is it really so that your Joe Average can't tell the difference between 1kWh of heat produced by gas compared to electricity? I get that pricing for different power sources may differ, but it's still watt-hours coming out of the grid. Optimizing their usage may obviously be worth the effort, but it's got nothing to do with power consumption.

So, please help me understand the situation a bit more in depth.

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[–] [email protected] 3 points 3 days ago

Full disclosure, I didn't watch the video yet, but it's likely a difference of environmental impact.

He's described in previous videos how burning gas at home is less efficient from the standpoint of a carbon footprint. I imagine this video is to help explain everything in a way that helps you come to that conclusion yourself. Teach a man to fish instead of just giving a fish and what not. So you can apply the knowledge to other things in your life

[–] [email protected] 0 points 2 days ago

I started to watch this video and gave up mid way. It spends like 15 minutes on gas stoves. Maybe I’ll revisit it.

Btw, I really liked his other video on microwaves.

[–] [email protected] -4 points 3 days ago (1 children)

I haven't watched it but its really simple. If you receive 1kW within 1hr and you compare that amount of power to 1kW over one second things are much different. The first is like a nice heater in a cold winter night...nice steady energy, a little bit of power. The second is like hell hole, tons of energy but still only a little bit of power. Power is the ability to do work or simply move things. Energy is the total amount of moving things regardless of the actual power used. So if you toasted a toast, that was a lot of power delivered quickly, but you could also do all that work slowly over centuries and eventually end up with the same molecular arrangement using the same amount of energy.

[–] [email protected] 2 points 3 days ago (1 children)

“1kW within 1hr” isn’t power. That’s energy.

“nice steady energy”? You mean nice steady power, right?

“The second is like hell hole, tons of energy but still only a little bit of power.” No. They are both precisely the same energy.

“So if you toasted a toast, that was a lot of power delivered quickly.” No. That is a lot of energy delivered quickly.

I typically wouldn’t be pedantic about this, except that this is precisely the point the video is making. These two unit types are often confused.

[–] [email protected] 2 points 2 days ago

“1kW within 1hr” isn’t power. That’s energy.

The watt is always power, not energy. I'm assuming OP here got some prepositions mixed up and meant 1 kW delivered for 1 hr. That amounts to an energy of 1 kWh.

The second is like hell hole, tons of energy but still only a little bit of power.” No. They are both precisely the same energy.

No, they are the same power. The energy in the case where 1 kW of power is delivered for 1 hour is 1 kWh. The energy in the case of 1 kW delivered for 1 s is about 0.28 Wh.

If instead 1 kWh was transferred over the course of 1 hour, that is an average power of 1 kW (but does not have to be uniform, without more information we can't know the power profile). If 1 kWh is transferred over the course of 1 s, that is an average power of 3.6 MW which is the example I think OP was getting at (ref. hell hole comment).

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