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> HN hates data on energy discussions.

>PV is now five times cheaper than fission. Onshore wind costs the same as PV. Batteries are easy to mass-produce.

This is an odd contrast of statements considering you gave no data to support your argument. I take issue with dismissing the massive problem of intermittancy and storage with "Battaries are easy to mass-produce".

"A cost-optimal wind-solar mix with storage reaches cost-competitiveness with a nuclear fission plant providing baseload electricity at a cost of $0.075/kWh27 at an energy storage capacity cost of $10-20/kWh. To reach cost-competitiveness with a peaker natural gas plant at $0.077/kWh, energy storage capacity costs must instead fall below $5/kWh."

https://www.cell.com/joule/fulltext/S2542-4351(19)30300-9

"The largest announced storage system, comprising more than 18,000 Li-ion batteries, is being built in Long Beach for Southern California Edison by AES Corp. When it’s completed, in 2021, it will be capable of running at 100 megawatts for 4 hours. But that energy total of 400 megawatt-hours is still two orders of magnitude lower than what a large Asian city would need if deprived of its intermittent supply. For example, just 2 GW for two days comes to 96 gigawatt-hours.

We have to scale up storage, but how? Sodium-sulfur batteries have higher energy density than Li-ion ones, but hot liquid metal is a most inconvenient electrolyte. Flow batteries, which store energy directly in the electrolyte, are still in an early stage of deployment. Supercapacitors can’t provide electricity over a long enough time. And compressed air and flywheels, the perennial favorites of popular journalism, have made it into only a dozen or so small and midsize installations. We could use solar electricity to electrolyze water and store the hydrogen, but still, a hydrogen-based economy is not imminent.

And so when going big we must still rely on a technology introduced in the 1890s: pumped storage. You build one reservoir high up, link it with pipes to another one lower down and use cheaper, nighttime electricity to pump water uphill so that it can turn turbines during times of peak demand. Pumped storage accounts for more than 99 percent of the world’s storage capacity, but inevitably, it entails energy loss on the order of 25 percent. Many installations have short-term capacities in excess of 1 GW—the largest one is about 3 GW—and more than one would be needed for a megacity completely dependent on solar and wind generation.

But most megacities are nowhere near the steep escarpments or deep-cut mountain valleys you’d need for pumped storage. Many, including Shanghai, Kolkata, and Karachi, are on coastal plains. They could rely on pumped storage only if it were provided through long-distance transmission. The need for more compact, more flexible, larger-scale, less costly electricity storage is self-evident. But the miracle has been slow in coming."

https://spectrum.ieee.org/energy/renewables/batteries-need-t...

"Given the magnitude of the battery material demand growth across all scenarios, global production capacity for Li, Co, and Ni (black lines in Fig. 3) will have to increase drastically (see Supplementary Tables 9 and 10). For Li and Co, demand could outgrow current production capacities even before 2025. For Ni, the situation appears to be less dramatic, although by 2040 EV batteries alone could consume as much as the global primary Ni production in 2019. Other battery materials could be supplied without exceeding existing production capacities (Supplementary Tables 9 and 10), although supplies may still have to increase to meet demands from other sectors5,9. The known reserves for Li, Ni, and Co (black lines in Fig. 4) could be depleted before 2050 in the SD scenario and for Co also in the STEP scenario. For all other materials known reserves exceed demand from EV batteries until 2050 (Supplementary Table 5). In 2019 around 64% of natural graphite and 64% of Si are produced in China32, which could create vulnerabilities to supply reliability."

https://www.nature.com/articles/s43246-020-00095-x




So storage reaches cost competitiveness with nuclear at $10-$20/kWh.

Do we know what the current cost is today?


I have no idea where you got these numbers, but nuclear energy is good for base load, while batteries are good for handling load peaks. These two types of load are very different.

With big batteries, nuclear energy can be accumulated at night and used at evening, which improve performance of nuclear stations a lot. Try it yourself at simulation: https://www.tennet.eu/fileadmin/user_upload/Our_Key_Tasks/In...

Current cost of power storage is below $100 per kWh stored in the newest designs.


It's a near verbatim quote from the Cell article in the post above mine.


~ $300 - $700 /kWh.

that figure could be outdated but its in the ballpark


So nuclear is much much much much cheaper and until the storage costs come way down, we have no other choice (aside from natgas peakers). Correct?


For baseline power the answer is yes. The only two forms of low carbon baseline energy we currently have are nuclear and hydro.


Do you know why California is using batteries instead of cheaper nuclear? Is it just for cynical political reasons?


No one is using batteries at a large scale at this point.


User "jeffbee" said that California has 250MW of battery facilities right now


I assume that's 250MWh, and California consumes 260 TWh per year, so that's 30s of power consumption.


No, it's 250MW of peak power. I'm not sure what the total energy storage capacity is for California, but the typical project has 4 hours of capacity.

For an example please see this PG&E project which is coming online in Summer 2021. These installations have 700MW of power capacity and each has a 4-hour discharge time.

https://www.pge.com/tariffs/assets/pdf/adviceletter/ELEC_582...


You're right about the numbers, but still this is tiny at the scale of the grid. 2.8GWh is still only around 5 mins of consumption. You would probably need a few days of storage to run a 100% wind/solar grid, so that's about 1000x more.


Nobody cares how bad the lifecycle efficiency is for pumped storage because the input doesn't cost anything.


That is only one of the multiple problems discussed with mass pumped storage. Regardless, the efficiency does matter as if you are attempting to store peak power as %100 of baseline power then your input is no longer free. It is a factor in the energy output of the PV / Turbine over the course of its lifecycle. Lower efficiency means more PVs / Turbines and more massive pumped storage projects.




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