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 13 hours ago

People complaining about this video have clearly not watched much Technology Connections; I enjoyed it immensely. It's right in line with how Alec normally does his videos. We who are loyal to the Great Alec expect the pedantic content.

[–] [email protected] 19 points 1 day ago (1 children)

In here absolutely everyone knows this stuff and it’s all just common knowledge.

[–] [email protected] 1 points 23 hours ago

Fair point, but basic physics has been a part of our education program for at least 60 years. Also for few years the 'exchange priced' or 'market valued' electricity has been somewhat popular and on the news, which adds up to the general understanding as if you know your stuff it means quite literal money as your bills are smaller. So, maybe 'absolutely everyone' is a bit of a stretch, but in general the majority of adult people understand the concept.

And also a ton of common folk understand it at least a bit on a deeper level as basic physics is included to studies beyond elementary school regardless on what you study. Sure, not everyone understands (or cares) how 3 phase AC in here adds up to 400V or why you need to have 2,5mm² wires for 16A fuse, but it's still pretty common that people, specially in a separate house, understand how you can only pull 2300W out of a 10A circuit or 3600W from a 16A one (10 and 16A being the most common fuses in a household in here).

[–] [email protected] 7 points 1 day ago

Also check out his other video on his Connextras channel where he basically suggests dismantling capitalism.

https://m.youtube.com/watch?v=Y2qSaD1v4cQ

[–] [email protected] 8 points 1 day ago

So I’m just wondering if this is really any new information for anyone.

It's never wise to underestimate most people's ignorance.

[–] [email protected] 13 points 1 day ago (1 children)

kW/kWh aren't commonly used outside of electrical applications in the US, so people are less readily able to quantify and compare in other contexts. Looking at a variety of natural gas companies' bills, you'll get volume multiplied by a therm factor instead of simply using kWh; horsepower for not just cars but even electrical motors and pumps.

I think the average person will have looked at their electricity bill and put the basics together about watts and watt hours. As for comparison with natural gas, I think he didn't touch on the real metric people then turn to- cost. Depending on the state it can be much cheaper to use gas vs electricity.

[–] [email protected] 2 points 1 day ago

Yeah, electric motors are what I notice the most. Be it on washers/dryers, garbage disposals (which range from 1/3, 1/2, 3/4, 1HP) and more.

[–] [email protected] 16 points 1 day ago (2 children)

Saved you a click: power = rate of energy use (energy/time)

[–] [email protected] 11 points 1 day ago

He says it so many times in so many ways that he actually starts to make it seem more complex than it is. You start wondering if you’re missing something, because you got it in 6 seconds but 12 minutes later he’s still talking about it.

[–] [email protected] 113 points 2 days ago (7 children)

If you think the average person understands watts, you live in a bubble, straight and simple. You have a very skewed notion of the average person.

[–] [email protected] 19 points 2 days ago (5 children)

Yep that video is leagues beyond most peoples capabilities to understand. Thinking they already knew and understood it is crazy.

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[–] [email protected] 117 points 2 days ago

I think you are greatly overestimating the basic functional knowledge of the general public...

[–] bdonvr 52 points 2 days ago

In here absolutely everyone knows this stuff and it's all just common knowledge.

Absolutely not. Not even close.

[–] [email protected] 15 points 2 days ago

After watching the video it was a bit over explained. I think he got his point across in the first 10 minutes, though I am an engineer by trade.

I appreciate his rigour in explaining and it is a good refresher on the power/energy calculations.

[–] [email protected] 36 points 2 days ago
[–] [email protected] 26 points 2 days ago (3 children)

Follow-up video idea: speed ≠ distance

[–] [email protected] 18 points 2 days ago (1 children)

The one that I think more people misunderstand is temperature Vs heat Vs something feeling hot/cold. One is a property, one is energy, and the other is the transfer of energy.

[–] [email protected] 6 points 2 days ago (4 children)

You know a nation of people who may not be able to articulate their understanding, but definitely have a high intuitive understanding of that?

We Finns.

100C sauna and no problem sitting on wood, but happen to touch something metal and oooh-weee.

Also same thing happens the others way around when it's - 20c outside. I don't think there's many people in Finland who don't have a core memory of what cold metal tastes like in winter, because of the resulting trauma. And it doesn't even need to be metal to stick.

Nicely explained.

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[–] [email protected] 51 points 2 days ago (4 children)

New Technology connections video drops:

I'm going to go buy a kill-a-watt.

[–] [email protected] 2 points 1 day ago

I moved into a tiny home and got one for measuring the current draw of my kitchen appliances and keeping track of the cost of my electric space heater ($40/month so far, yeesh)

[–] [email protected] 7 points 2 days ago (1 children)

Do it, it teaches you things.

Most of your power isn't going where you think.

[–] [email protected] 2 points 12 hours ago* (last edited 12 hours ago) (1 children)

Oh I love this stuff.

My dishwasher pulls over 1000W, but overall actual usage pales in comparison to my server cluster, which utilizes a multiple 35W mini PCs.

I started measuring a bunch of things in February (using zigbee-compatible smart plugs to HA), so here is a graph of the above for the entire month of March:

It was eye opening, to say the least.

[–] [email protected] 1 points 9 hours ago

Yeah, my rack is a beast too, especially since it runs 24/7.

I have PGE though, so I get absolutely reamed constantly, they play a lot of games so my solar helps me as little as possible.

Oh, I had a whole-house meter connected to my smart meter by zigbee, but then PGE disabled that a few years ago.

Worst part of california :(

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[–] [email protected] 12 points 2 days ago (1 children)

is it really so that your Joe Average can’t tell the difference between 1kWh of heat produced by gas compared to electricity?

Most people don't even know what a watt or watt/hour is. And have no idea how energy from gas relates to energy from electricity.

[–] [email protected] 6 points 2 days ago (3 children)

watt/hour

Oh yeah I've seen that used before, makes me cringe every time.

Anyway, do must people not go to high school? Or is stuff like that not part of the physics curriculum in some places?

[–] [email protected] 7 points 2 days ago (1 children)

A W/h either is a big problem or will be soon.

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[–] [email protected] 4 points 1 day ago

Even if it was covered in high school, I think because most people never use it again in daily life it's easy to forget.

[–] [email protected] 4 points 2 days ago (6 children)

In my highschool physics was optional. You had multiple options for science credits and could get through without taking it.

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[–] [email protected] 11 points 2 days ago (2 children)

He’s making a point about instantaneous versus overall energy use, which it sounds like you already understand. “Power” and “energy” are already kind of loose terms, which could make that conversation confusing IMO.

But for anyone confused by this:

For the typical energy consumer, Watts (W, kW) are relevant when considering circuit capacity. Otherwise, Watt-hours (Wh, kWh) is likely the metric you’re looking for when considering energy use.

Concretely, your coffee maker might pull 1.2 kW while in use, more than most appliances in your house, yet it probably represents a minuscule portion of your electric bill, perhaps less than 1 kWh, since it only needs to boil a small amount of water with each use.

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[–] [email protected] 15 points 2 days ago (1 children)

There's no way even 1% of people understand this in the world. Maybe 1% know of those measurements "existence" asking them what they are would get an "uhh"

[–] [email protected] 5 points 2 days ago (4 children)

In the world? Me and millions of other people got this info in middle school physics. Sure, maybe we mostly forgot the details by now. But it's not arcane or ancient knowledge lost to time. It's in your electricity bill every month. A quick visit to Wikipedia and I got the gist of it back. Every single physicist, engineer, and electrician got this explained again to them.

[–] [email protected] 2 points 1 day ago

"a quick visit to wikipedia" is a good example confirming what I said, majority of people are not willing to do that to learn any subject. 0.483% of humans are engineers, of that I'd say there are a small chunk that are near worthless and probably don't even know these basics.

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[–] [email protected] 33 points 2 days ago* (last edited 2 days ago) (3 children)

lot of people from the US 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

Right, because for most people gas is metered and sold by the CCF, and not converted into kW at any point in the chain.

So I know i used 30ccf last month, but there's zero indication what that is in kW, because we usually don't convert between the meter (which is volumetric) and the billing, which could be anything but why bother?

[–] [email protected] 13 points 2 days ago

Reticulated gas is charged by the kWh here in New Zealand. The meter may well be calibrated in m³ (I don't have gas at home, so I don't know for sure) but all pricing is energy, not volume.

For bonus points, if instead you buy your gas in cylinders - a pair of 45kg (~100lb) cylinders is a common installation for houses without piped gas - those are sold simply by the unit. The best conversion for that I can find is one energy retailer describing one 45kg cylinder as 2200MJ (611kWh).

I expect this is one of those things that is overall horribly inconsistent depending on where you live.

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[–] [email protected] 21 points 2 days ago (3 children)

Power is water throughput in a pipe, energy is water filling a bucket. Simplest way I've found to explain it in my 15 years in the energy space.

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[–] [email protected] 26 points 2 days ago* (last edited 2 days ago)

is it really so that your Joe Average can’t tell the difference between 1kWh of heat produced by gas compared to electricity?

Yup.

I totally understand electricity because it's pretty intuitive. Everything is advertised in watts, my bill comes as kilowatt hours, so it's pretty easy to calculate how much energy something uses by plugging in a kill-a-watt and measuring it.

My gas is billed in therms. I don't really know what that is, nor do I know what the flow rate is for my furnace or gas stove, so I have no concept for how much energy I'm using. I don't have an electric one to compare with, so I that's not an option either. So how exactly would I get to the point where I would be able to compare the two without a lot of annoying testing? Even then it would be extremely imprecise.

And no, it's not "watt hours coming out of the grid," except in the pedantic sense that they can be converted. They come from very different sources, so it's like comparing an EV to a horse, and while you could, it's completely nonsensical.

But yes, at some base level your average American knows there's a connection between the two (after all, I can choose between electric heat/heat pump and a gas furnace), but they'd rely on an expert to estimate the monthly price difference between options, since that's ultimately what we care about. The problem is mentioned near the end of the video, HVAC experts don't seem that familiar w/ heat pumps, so you may not get a decent estimate, depending on who your technician is. And that adds to the misinformation.

[–] [email protected] 34 points 2 days ago

haven't seen it so far, but technology connections will always get an upvote.

also consider subscribing to his channel, his videos are amazing.

[–] [email protected] 13 points 2 days ago

I sometimes make a conscious effort to understand electricity. For a few days, I then think I understand what's going on and then promptly I forget.

(Yes, I shall watch this video.)

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