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Comment by s0rce | Hacker News Reader

Seems like CA might has 15-20GW of spare NatGas generation capacity. Looking back at the summer peak (9/6/20) I see 25GW generated at the peak, while we are currently only needing to generate about 8-9GW from NatGas (looking over night when solar drops off).

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The parent said there is not enough transmission capacity not generation capacity. Generation needs to be near loads. If not then transmission lines are required to bring current from generators to loads. Transmission lines have fixed capacities, like your internet connection can only transmit so much data/s, they can only transmit so much power.

It's likely that the transmission lines are less of a bottle neck than the frequency conversion. Power lines are pretty darned efficient, and given the cold weather, theyd be more efficient than usual too

That actually isn't true:

https://3dfs.com/articles/wasted-electricity-vs-lost-electri...

Almost 62% of electricity is lost in the grid. AC is the primary reason (matching, vibration, I2R, etc.).

HVDC is WAY better at transmitting power over any appreciable distance.

The Chinese have an amazingly ambitious plan to shift power from one part of the country to another with UHV DC. It has its own challenges, but it is definitely the way to shift massive amounts of power without grid interconnect (and the resulting frequency stability issues). Much lower loss, even with DC-AC converters.

https://spectrum.ieee.org/energy/the-smarter-grid/chinas-amb...

If America built a network of 20GW HVDC interconnects it would be far more significant infrastructure than building some highways.

The article is wildly incorrect: the 62% figure includes the losses during generation e.g. heat lost when burning coal or cooling towers for nuclear.

I recall that losses after generation due to transmission across the electricity grid are typically about 10%.

They make long distance DC innerconnects, while expensive they are resistant to particular types of problems and can connect to multiple different grids at the same time.

there has been a 3GW DC interconnect between Portland, OR and LA for 5 decades or so. https://en.wikipedia.org/wiki/Pacific_DC_Intertie

Electrical engineers wouldn't build a power line to Texas with a capacity of 5000 MW and then put intertie hardware such as phase shifters or ac-dc-ac converter with capacity of 1000 MW on the end of it. So it is likely that the transmission capacity and intertie capacity are exactly the same!

It's not the capacity of the converter, it's the efficiency of the conversion. There's some loss involved.

I thought they were saying there wasn't enough transmission capacity but it wouldn't matter anyways since the rest of the grid didn't have any to spare. Maybe I misinterpreted or responded to the wrong comment.

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