A note on energy conservation

Due to the Fukushima Nuclear Power Plants being offline, the Kanto area is experiencing serious power shortages. According to Tokyo Vice-Mayor Inose Naoki as of  around 4:30pm, the electricity demand in the Tokyo Power area exceeded the supply by 1/3, and therefore a 1/4 reduction in electricity consumption will be necessary to avoid rolling blackouts in the near future.

What you see above is a map of Japan’s electrical grid, which for odd historical reasons is separated into a 60hz grid (same as North America) in the western half of Japan and a 50hz grid (same as Europe) in the eastern half. As you can see, the blue areas on the above map are the 60hz region and the red areas are the 50hz region. Although there is a crossover in the middle that allows frequency conversion, it is not high enough capacity for the Kansai (west Japan) grid to have much effect in compensating for the shortages in Kanto and Tohoku (east and north-east Japan).

According to Osaka City Mayor, Hiramatsu Kunio, the crossovers between the two systems only transmit a total of 1 million kilowatts, which is a smallish percentage of the electrical shortage volume in Kanto, which according to Inose’s statement was 10 million. Since there are also no energy issues going on in Kansai, there should still be enough power available to feed the 60hz/50hz crossover even without energy conservation efforts, and Hiramatsu has stressed several times that no extraordinary energy conservation measures are necessary at this time, and if they are deemed necessary later there will be an announcement.

Of course this does not mean that conservation is a bad idea – it never is! Residents throughout Japan would be well advised to take reasonable conservation measures, such as for example using gas or oil heat instead of electricity, whereas residents of the 50hz Kanto region should be conserving as much power as possible to help reduce the odds of a total blackout.

Update: Sounds like the national government just called for nationwide energy conservation, but my point still stands. Electricity conservation is FAR more critical for people living within the 50hz region.

[Update: March 14 2:10pm] Rolling blackouts have been scheduled for Tokyo, but due to successful power saving measures, especially suspending operation of many trains, this morning’s blackouts were avoided. Details of the blackout regions and schedule can be found here.

According to Tokyo Vice-governor Inose Naoki, some time in the next few weeks an additional thermal based power plant (natural gas or oil I presume, but unclear) with a capacity of 7 million kilowatts – which will go most of the way towards filling the 10 million kilowatt gap between the ordinary electricity demand load and the current available supply. I can’t find any other details as to what plant he is referring to, or what it has been doing this whole time.

On a lighter note, fans of the anime series Evangelion have half-jokingly began referring to energy saving measures as “Operation Yashima” (ヤシマ作戦) after an event in an episode of the show in which the output of the entire electrical grid of Japan is redirected into a massive energy weapon in order to defeat an invading alien creature. One fan has also made a nifty poster calling on people to save power in the graphic style of Nerv, the fictional government agency in the Evangelion series.


11 thoughts on “A note on energy conservation”

  1. 5 groups for rolling blackouts, tokyo-to and 8 kens, but I can’t find for the life of me which groups are scheduled for when. tepco site is overwhelmed and just throws up an error.

    An error occurred while processing your request.
    Reference #97.15911d78.1300016614.48c062

    From the nikkei
    2011/3/13 20:16


  2. Thanks. found it a bit after posting. Still not understandable without clarification from tepco, since the same cities show up in multiple groups. And out of the 23 wards, only arakawa is listed.

  3. I’ve been wondering how many of the power plants in Japan – especially the nuclear ones – went on some kind of standby as a result of the quake/tsunami, and how much of the system was back at capacity.

    There was a case in Hawai’i a few years ago when a small quake triggered the emergency cut-off system, causing a cascading blackout across most of Oahu (while the quake was centered on Hawai’i).

    This is serious, though: if the Fukushima plants are that critical for Tokyo area power, and these plants aren’t going to be up and running again for the forseeable future, then some kind of massive boost in the converted power transmission seems like a critical immediate project.

  4. Near as I can tell there were 4 Nuclear stations, all with multiple reactors, shut down.

    Fukushima I — 6 reactors (+2 planned), combined 4693 MW
    Fukushima II — 4 reactors, combined 4400 MW
    Onagawa — 3 reactors, 2174 MW
    Tokai — 2 reactors, 1266 MW

    The first 3 plants at Fukushima I sound like they are not going to be running anytime soon, and reactor #1 may never be used again.
    I could be wrong here but working on what little I know, all the others should be able to return to operations in the future. The issue is what kind of timeline will it take to get them inspected, certified, and go ahead to return to service? I haven’t a clue if that process is months or years ??
    Those 3 reactors from Fukushima I, which almost surely will not return to service or will take years to return to service, represent around 2028 MW. The other 3 reactors at Fukushima I were already down for service and refueling, and may have a comparably faster time returning to service? They represent 2668 MW.

  5. “odd historical reasons”? More like eastern Japan had its electric infrastructure originally built by Germany, and western Japan by the U.S.

  6. Thanks for the clarification. But that is certainly a historical reason, and I would still call it “odd” that they chose to build two incompatible grids without realizing the problems it would cause down the line, sort of like the dueling AC and DC grids that used to exist in the US.

  7. I’d call it odd as well. And pretty damned inconvenient.

    (Cf. “American” Sign Language)

Comments are closed.