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Power Grids: The Huge Battery Market You Never Knew Existed
ashshy writes Unlike the obvious battery needs for smartphones or electric cars, many consumers are unaware of the exploding need for enormous battery banks as modern power grids are bringing a whole new set of requirements. From the article: "'Our electricity grid was built a certain way, and that way is to have on-demand production,' Argonne National Laboratory battery researcher Jeff Chamberlain explained. 'So as I flip my light switch on at home, there's some little knob somewhere that turns the power up. There is no buffer. It's a very interesting production cycle compared to other consumer goods. It was built a certain way, and the grid is currently changing in two different ways. One is, first our demand is increasing. But another is, around the world human beings are trying to get off fossil fuels and that means using solar and wind. Well, we cannot turn up the sun or wind, or turn down the sun or wind according to our energy needs. So the more those technologies penetrate the grid, the more you need energy storage. You need a buffer. And that is a very difficult challenge that's similar to transportation because it's cost-driven,' Chamberlain said. 'But it's also different from transportation because we're not limited by volume or mass like we are in vehicles. We're working on energy storage systems that are stationary.'"
Umm, no.
Former Naval Nuke guy here...we didn't run the plant at full power most of the time. We seldom ran it at half power.
Yeah, the nuke plant on a sub or surface ship is engineered differently than a power reactor ashore. Among other things, the fraction of the maximum output dedicated to making electricity is generally quite small, since we need steam more than we need electricity.
Even so, we didn't operate near max electrical output all that often either, much less maximum steam output.
"I do not agree with what you say, but I will defend to the death your right to say it"
Pumped storage ... needs specific geography, high and low reservoirs close to each other to reduce losses pumping water uphill over long distances. It also needs a guaranteed supply of water, lots of it and the sunny parts of the US where large amounts of solar power are being generated are distinctly lacking in water
One only needs a low reservoir (see the Taum Sauk). Furthermore, while pumped storage certainly isn't a good idea in the Southwest, it is ideal in the Great Lakes area, where there's tons of wind resources (see: Iowa, Minnesota, etc.). And, as it turns out, there is a (functionally) infinite supply of water in Lake Michigan and a functionally infinite amount of land with delta h on the West Coast of Michigan, which has hills immediately adjacent to the Lake due to thousands of years of wind blowing from Wisconsin to Michigan. A storage plant like this already exists, just south of Ludington MI. We could easily build 100 GW worth of pumped storage there, equal to the capacity of all nuclear power in the US.
Pumped storage is also lossy, typically about 65% efficient round-trip.
My experience is that the average is closer to 75%, and it can be as high as 90% with modern, well maintained pumped storage. Pumped storage also has extremely fast ramping capabilities, making it very useful for the minute-by-minute operation of the grid. Of course pumped storage, like all major power plants, requires transmission investment to be fully useful.
Grid gas, coal and nuclear generators don't need storage as they either run flat out to meet the instantaneous demand and they can throttle back in quieter times.
Nuclear, coal, and gas steam plants have very real operational limitations. Nuclear is almost never ramped back to follow load; it's cheaper in the long run to pay negative locational marginal prices (LMPs) if need be. Coal and gas steam can only ramp a few MW per minute, and have minimum outputs whereby they can't maintain power any lower -- and that's often at about 50% of capacity. At that point, any lower output requires a shut down, and then a 12-30 hour cool down whereby the unit can't be restarted. Nuclear, coal, and gas steam are extremely inflexible generators relative to hydro, gas/oil CT, and even gas CC.
At the moment intermittent wind and solar generators use the grid as free storage but the more intermittent power that is added to the generating mix the more that storage will be needed to deal with peak inputs and debits.
Free storage? Wind and solar fueled generators, like all generators, sell the energy instantaneously. Your metaphor makes no sense. All operating power plants sell in real-time. Same price for the same power. Eventually, substantially more storage will have economic value, but on the mainland US grid, not for a long time. California is poised to have 33% renewables by 2020, and they don't need additional storage. (There's an order for ~1.5 GW of storage to be procured, but it's not needed -- it's CA's way of pushing progress forward, seeing that eventually storage will be a less expensive resource (LCOE) than CTs.) Most other parts of the mainland won't have exceeded 10% non-dispatchable renewables by then.
Getting wind and solar farm operators to pay for this extra storage probably isn't going to happen, sadly.
Why should they? In most of tUSA, there's a day ahead and a real time market. Power has a price (LMP). Generators can sell into that market or not. When supply exceeds demand, the LMP goes negative, and all generators who are operating are equally responsible for the problem; all generators who are operating at those times pay the same financial penalty. That includes operating wind and solar and the nuclear and gas and coal that can't turn down.
In the mean time, the number of MWh that are curtailed is a tiny, tiny fraction of the total MWh consumed in America. Storage simply isn't very valuable on the American grid right now because we
Support a few technologists in Washington.