What’s in a Kilowatt Hour?

The current price spikes for electricity in Europe has driven a new interest in saving energy, and part of doing that is to understand just how much energy different things use. I realized while I knew that modern LED lights are magically efficient, just how much electricity is used by other machines? No idea! So, I set out to find some examples the utility you get from a one kilowatt hour of electricity.

Updated in November 2022 with additional data.

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A Few Electrons too Many

Adding electronics to systems that used to be mechanical has been the great wave of innovation for a quite a while now. Modern transportation just would not work without all the electronics and computers inside (someone once quipped that a modern fighter is just a plastic airplane full of software), and so much convenience has been provided by automation and smarts driven by electronics. However, this also introduces brand new ways that things can break, and sometimes I wonder if we really are not setting ourselves up for major problems when the electrons stop flowing.

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Off-Topic: Another Troubled Train

sj-logo_largeAlmost exactly a year ago, I wrote a blog post about an adventure with delayed trains getting from Uppsala to Stockholm. As I said then, I am a train fanboy, preferring trains to most alternatives for most travel. Trains do have one big disadvantage though: when something goes wrong, you are unusually powerless and stuck. That happened to me last Friday. I spent some five ours in a dark train in a dark winter evening in the middle of the forest south of Laxå. Here is the story of that journey, and an observation about the impact of technology on our lives.

It was on a Friday the 13th, by the way. Not that I believe in that bad luck happens more on certain days, this certainly was an unlucky Friday (and very early Saturday).

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A Weekend in the Netherlands

We spent the past weekend in the Hague and Delft in the Netherlands. A short weekend trip, certainly, but still quite interesting. The obvious place to go visit in the Netherlands is Amsterdam, but these other places are well worth visiting too. Here are some observations on what I found interesting.

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Off-Topic: Triple Train Trouble


I am a big fan of trains, I admit as much. I take the train almost every day to Stockholm, and I find that far superior to the stress and misery of driving a car or the poor comfort of a bus. I have always defended the railroad when people complain that trains are often late and unreliable.

But recently there have been a few cases of really bad delays hitting me… a couple of weeks ago, I missed a meeting at KTH by about 45 minutes after the train’s brakes broke. And today, we had an absolutely monumental delay — I arrived at my office some two-and-a-half hours late, which is pretty amazing (or abysmal) for a 40 minute train ride.

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Off-topic: The Train to Furuvik

This is a short travel tip for the Uppsala-Stockholm area. Yesterday, I used the UL train to get to the Furuvik zoo/amusement park close to Gävle. Compared to the visit we did last year using a car, taking the train was generally a superior experience. And cheap. For 200 SEK, you get two adults + three children, with all rides included. Much cheaper than going there by car and then buying the rides. Not having to spend an hour driving with children is also a clear advantage in my mind, rather you can relax on the train and have fun with the kids. Being tired at the end of the day, I was very happy not to have to drive home.

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Travel Tip: Tokyo Trains

I am just back from my first ever trip to Tokyo, and it was a very interesting experience. I am very impressed by the Tokyo train system, and I cannot understand why some foreigners seem to avoid it and use taxis instead. All stations have signs in English (at least all that I visited in Tokyo), and the system is mostly very reliable and predictable. There are some things that I would have like to know before I came there, however, which were not entirely obvious.
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