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California breaks 1 GW energy storage milestone

pv-magazine-usa.com

11–20 of 61 posts

Re: California breaks 1 GW energy storage milestone

#11
post #10

Energy storage projects are typically described in terms of maximum power (megawatts) and hours of supply at peak power. Multiplying hours and megawatts gives megawatt hours, a unit of energy. Gigawatts and gigawatt hours are just different magnitude units for the same power and energy values, like meters and millimeters. Most electrical grids experience peak demand in the early evening when people come home from wor…

Everything about these storage projects is available as public records from the CPUC, down to the site plan drawings.

Thanks! I've been noticing these projects mostly from press releases that surface through Google News, and those don't always provide both numbers. It's good to know that there is a detailed source of open data.

Re: California breaks 1 GW energy storage milestone

#12

Take a shot every time the article uses "GW" and "MWh/GWh" apparently interchangeably for "energy" or "power", also seemingly at random.

Actually, I thought it was very easy to understand. For instance,

> Fortunately, 2,000 MW of energy storage capacity is coming online by August 1, per the California Public Utility Commission. Much of this capacity will have four hours of battery energy sitting behind it, nearly 8,000 MWh in total.

That's 2 GW of power delivery backed by 8 GWh of storage.

Re: California breaks 1 GW energy storage milestone

#13
post #3

Earlier quoted context omitted.

"My car runs 100 miles!" instead of "My car runs 100 miles per gallon!", and almost anyone would notice something is amiss. I don't get the difference to mixing "Watts" with "Watts/hour".

Energy is not Watts per hour (Watts/hour), it's Watts times hours (Watt-hours). Sorry for pedantry, but the units are the topic of discussion here.

[deleted]

Re: California breaks 1 GW energy storage milestone

#16
post #15
post #14

This is only counting batteries. California has an additional 4 GW of pumped storage capacity.

Did you mean GWh?

No, GW -- as in the pumped storage facilities can deliver 4 GW of power continuously.

The amount of energy that can be stored in California's pumped storage projects is enormous, measured in hundreds, if not thousands, of GWh, but that's mostly irrelevant to this discussion.

Re: California breaks 1 GW energy storage milestone

#17
post #7

Earlier quoted context omitted.

> Gigawatts and gigawatt hours are just different magnitude units for the same quantities, like meters and millimeters. I liken it more to distance vs speed. Power, like speed, is a rate, in particular the instantaneous rate at which energy is transferred. Expressed using the same scheme we use for speed (distance per time : power per time), power is watt-hours per hour (or 0.0036 megajoules per hour). I'm guessing w…

I meant the "giga" units relative to their "mega" counterparts. Same physical quantities but multiplied by 1000.

Hmm, in that case your comparison should be from MW to GW, not GW to GWh, right?

Re: California breaks 1 GW energy storage milestone

#19
post #17

Earlier quoted context omitted.

I meant the "giga" units relative to their "mega" counterparts. Same physical quantities but multiplied by 1000.

Hmm, in that case your comparison should be from MW to GW, not GW to GWh, right?

I referred to megawatts and megawatt hours in my first two sentences. "Gigawatts and gigawatt hours" was indicating counterparts to MW and MWh. Though apparently that grammatical construction was not as clear as I initially believed.
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