Japan Building Giant Battery Systems to Store Solar Power • Hacker News Board

Re: Japan Building Giant Battery Systems to Store Solar Power

#11

Post by Someone » Wed, Jun 24, 2015, 10:42 AM UTC

markvdb wrote: post #3

50000 kilowatt, for how many milliseconds? The phone in my pocket has a 500 _giga_watt battery. What a pity it's only 700mAh...

No, it has not. You cannot get the energy out of that battery that quick.

That makes a huge difference. For example, TNT has about a tenth of the specific energy per kg of gasoline (4.6 MJ/ kg vs 44 MJ/kg; https://en.wikipedia.org/wiki/Energy_density), but is more useful as a bomb because you can get the energy out very quickly.

If you could get that amount of power out of a mobile phone, it would probably be a bomb.

Re: Japan Building Giant Battery Systems to Store Solar Power

#12

Post by tempodox » Wed, Jun 24, 2015, 11:14 AM UTC

Finally someone starts putting two and two together. Mankind's preoccupation with lethal / more dangerous power conversion methods has lasted more than long enough.

Re: Japan Building Giant Battery Systems to Store Solar Power

#13

Post by Hermel » Wed, Jun 24, 2015, 11:30 AM UTC

That's 600 MWh for 257 million USD. Tesla's powerwall has 10 KWh for 3500 USD. Interestingly, that's about the same price point.

Efficiency-wise, the centralized Japanese solution makes probably more sense for large centralized solar plants, whereas Tesla's model probably makes more sense for self-owned solar panels.

Re: Japan Building Giant Battery Systems to Store Solar Power

#14

Post by Retric » Wed, Jun 24, 2015, 11:39 AM UTC

Hermel wrote: post #13

That's 600 MWh for 257 million USD. Tesla's powerwall has 10 KWh for 3500 USD. Interestingly, that's about the same price point. Efficiency-wise, the centralized Japanese solution makes probably more sense for large centralized solar plants, whereas Tesla's model probably makes more sense for self-owned solar panels.

Upfront costs might be similar though this includes total costs (Land, installation, AC-DC converter, etc) where the tesla does not. However, efficiency is probably higher and the matence costs are probably far lower.

PS: The tesla battery actually claimes an 'inflated' effecency level (92%), by not including inverters, though as it's designed for DC solar systems that may be reasonable.

Re: Japan Building Giant Battery Systems to Store Solar Power

#15

Post by gjem97 » Wed, Jun 24, 2015, 11:42 AM UTC

markvdb wrote: post #3

50000 kilowatt, for how many milliseconds? The phone in my pocket has a 500 _giga_watt battery. What a pity it's only 700mAh...

The internal resistance of a battery limits the amount of current that it can produce: https://en.wikipedia.org/wiki/Internal_resistance

Re: Japan Building Giant Battery Systems to Store Solar Power

#16

Post by Ntrails » Wed, Jun 24, 2015, 11:45 AM UTC

dvdkhlng wrote: post #10

jmadsen wrote: post #6

"the lack of compatibility between regional power utility grids." For folks outside the country, the grids here are actually like 19th century European railroad gauges in different countries. Meaning, after the tsunami in the north, when the nuclear power plants were shut down, they literally could not move electricity from one part of the country to another where it was needed (or could, but it was crazily difficult…

Yes, japan is split into a 60 Hz (west) and a 50 Hz (east) power distribution systems. They do have four main frequency converter stations that can move power between the two networks, three of them are shown on this power distribution map: https://en.wikipedia.org/wiki/Shin_Shinano#/media/File:Power... Taken together they have a capacity of around one Gigawatt. Here is some more information on the used technology: h…

Taken together they have a capacity of around one Gigawatt.

Not even enough to power a flux capacitor :(

Re: Japan Building Giant Battery Systems to Store Solar Power

#17

Post by mikekchar » Wed, Jun 24, 2015, 11:57 AM UTC

Google doesn't help me, but my wife often tells me that our area (along the coast of Suruga bay in Shizuoka prefecture) has the most annual sunshine in all of Japan (I won't argue with her ;-) ). Definitely the number of solar installations here is dramatically rising. Practically every day I see a new one. 5 years ago it was wind turbines (it's also insanely windy here most of the time...)

Shizuoka is home to a very large amount of car and motorcylce manufacturing and after the the Tohoku earthquake they got creative with scheduling workers based on available power. My understanding is that the big manufacturers made a rota took turns using the power. If they manage to get a very large amount of solar power running (which it definitely looks like they are aiming for), I wonder if they will end up scheduling work based on the weather report.

Re: Japan Building Giant Battery Systems to Store Solar Power

#18

Post by vermontdevil » Wed, Jun 24, 2015, 1:34 PM UTC

jmadsen wrote: post #6

"the lack of compatibility between regional power utility grids." For folks outside the country, the grids here are actually like 19th century European railroad gauges in different countries. Meaning, after the tsunami in the north, when the nuclear power plants were shut down, they literally could not move electricity from one part of the country to another where it was needed (or could, but it was crazily difficult…

How did that happen?

Re: Japan Building Giant Battery Systems to Store Solar Power

#19

Post by Jedd » Wed, Jun 24, 2015, 1:35 PM UTC

Hermel wrote: post #13

That's 600 MWh for 257 million USD. Tesla's powerwall has 10 KWh for 3500 USD. Interestingly, that's about the same price point. Efficiency-wise, the centralized Japanese solution makes probably more sense for large centralized solar plants, whereas Tesla's model probably makes more sense for self-owned solar panels.

I gather that Tesla's model is also targeted at people who may also wish to start storing power they buy off the grid at times when the cost is lower (as well as from locally generated solar, turbines, etc).

Price point commonality may be more coincidence than anything else. There's a philosophical question in there for some (probably small) number of customers -- whether they wish to remain beholden to vendors of electricity, at whatever rate is determined by the vendor at the time.

Re: Japan Building Giant Battery Systems to Store Solar Power

#20

Post by dvdkhlng » Wed, Jun 24, 2015, 1:47 PM UTC

vermontdevil wrote: post #18

jmadsen wrote: post #6

"the lack of compatibility between regional power utility grids." For folks outside the country, the grids here are actually like 19th century European railroad gauges in different countries. Meaning, after the tsunami in the north, when the nuclear power plants were shut down, they literally could not move electricity from one part of the country to another where it was needed (or could, but it was crazily difficult…

How did that happen?

Quoting from https://en.wikipedia.org/wiki/Energy_in_Japan#National_grid

"The two grids were originally developed by separate companies. [..] In 1885 demand had grown enough that TELCO bought generation equipment from AEG of Germany. The same happened in the western parts of Japan with General Electric being the supplier to Osaka Electric Lamp. GE's equipment used the US standard 60 Hz while AEG's equipment used the European standard of 50 Hz."

AFAIK they never managed to convert the network to a common frequency due to cost concerns and politics.