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Japan Power Hardware

Japan's Richest Man Outlines Renewable Energy Plan 224

itwbennett writes "Speaking at the launch of his Japan Renewable Energy Foundation, Masayoshi Son, founder and CEO of Softbank, outlined a plan to rebuild Japan's energy infrastructure. Son said the country could shift to renewable energy sources for 60 percent of its electricity requirements over the next two decades. He called for a 2 trillion yen (US$26 billion) 'super grid' across the country, and underwater off the coast, that would zip electricity around cheaply and efficiently to meet demand."
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Japan's Richest Man Outlines Renewable Energy Plan

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  • by gstrickler ( 920733 ) on Monday September 12, 2011 @05:39PM (#37381176)

    Japan is one of the few places that could possibly be powered completely by geothermal. There isn't nearly enough wave energy to supply the planet, nor is there sufficient wave energy near Japan to supply Japan. With a combination of geothermal, wind, hydro, and possibly some solar or wave, Japan might be able to go completely renewable. Most industrialized countries don't have access the the abundant geothermal resources Japan has (due to their location on the edge of the "ring of fire").

    Of renewable sources, solar and wind are the ones that can supply enough power for the world, but both are intermittent sources that are not well suited to supplying either base-load or peak-load power without a significant amount of on-demand energy storage added to the grid. On demand energy storage can be in the form of batteries, super capacitors, gravity reservoirs (e.g. pump water uphill to a reservoir during periods of excess generation, release it through turbines when needed), etc. However, solar requires huge amounts of land. Solar and wind each need more than 4x average demand installed (even with on-demand storage, more still without on-demand storage) because they only average ~25% of installed capacity. Neither solar or wind is viable in all areas, and with it's intermittent nature, the grid must have significantly more capacity to route from locations with excess to locations with a shortage.

    Bottom line, for most of the world, nuclear and/or fossil fuels are the only currently viable means to meet the difference between renewable capacity and peak demand. Fossil fuels will be exhausted in 50-250 years (~50 yrs oil, slightly longer for natural gas, 200+ years coal). Since plants have a 40-80yr life span, fossil fuel plant built today, could run out of fuel before the plant is used up. Nuclear is the only long term solution that is viable today, and even that needs to move to a thorium fuel model with breeder reactors and fuel reprocessing in order to last more than a few hundred years.

  • by Rei ( 128717 ) on Monday September 12, 2011 @05:51PM (#37381278) Homepage

    AC under seawater is difficult. DC under seawater is simple. Both AC and DC suffer from resistive losses in the cable, but AC also suffers from reactive losses, which are far higher underwater. You can even do earth return, either a monopolar transmission or an uninsulated (and thus cheaper) return wire. And no, it's not dangerous; it's already used in quite a few places.

    What is being proposed here is a nationwide HVDC grid, which is an especially important thing in Japan where they have basically two separate AC grids operating on different frequencies. This prevented the southwest from sharing power with the northeast after the tsunami, causing the northeast (including Tokyo) to suffer rolling blackouts for a long period of time. DC can allow power sharing between the two grids.

    Basically, it's a proposal to allow power generated in any part of the country to be consumed in any other part, with minimal losses. And seeing as the country is the size of California, the weather in one part of the country can be very different than the weather in another part of the country, so it's a boon to not just stability and efficiency, but renewables capacity as well. Peaking plants and energy storage systems anywhere in the country can likewise support the entire nation.

    I certainly hope Japan leads the way on this. Europe has been moving in this direction at a moderate pace, but the US only at a snail's pace. It needs a big push.

  • by Asic Eng ( 193332 ) on Monday September 12, 2011 @06:15PM (#37381484)

    ...50 or 60 cycles?


  • by Sir_Sri ( 199544 ) on Monday September 12, 2011 @06:19PM (#37381514)

    We run thousands of cables that support electricity across the ocean including to the coast of japan now. They are lower energy, but the principle is the same. Sure, an earthquake could wreck a cable, but it's a lot cheaper (and faster) to replace a cable than a power generator. Build the generators in safe (by japanese standards) places, and put the risky stuff on wires that can be replaced and turned off.

  • by JanneM ( 7445 ) on Monday September 12, 2011 @06:24PM (#37381542) Homepage

    "Say what you want, but Softbank really brought the iphone revolution"

    No, not really. They were a newly started/aqcuired network (softbank bought a failing network wholesale) with few customers and a reputation for lousy infrastructure. They were the only network willing to accede to Apple's conditions for selling the iPhone (rumour has it Apple was holding out for NTT Docomo to the end but the negotiations fell through). Apple got a compliant network and Softbank got a cash cow to drive subscribers.

    But Softbank only "brought the iPhone revolution" because they were the only network willing to bend to Apples conditions.

  • by Rei ( 128717 ) on Tuesday September 13, 2011 @02:27AM (#37383844) Homepage

    Reactive losses *are* losses. They heat the wires []. Reactive reserves for phase stabilization can help get that back under control, but they don't undo the losses already in the wires. Reactive losses are a well known issue with submarine AC cables and limit their length.

    DC not only is viable, as the person below you notes, it's already *in use*. The majority of new long-distance high power links being strung up in Europe [] (red=existing, green=under construction, blue=proposed), and a number in North America [] as well, are HVDC. Learn about it. Conversion is now efficient and no longer nearly as expensive using modern thyristor-based digital converters. Long-distance HVDC links are much more efficient than long-distance AC links.

    Enough of this "I'm pontificating about a subject I've never read about" nonsense.

"Well, it don't make the sun shine, but at least it don't deepen the shit." -- Straiter Empy, in _Riddley_Walker_ by Russell Hoban