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Comment by throwaway10122 | Hacker News Reader

Doesnt China have it's own supply of deserts a bit closer to home?

Part of the idea is that the producer and consumer of the energy are on opposite hemispheres and at different longitudes. That means when its winter in China, it is going to be summer in Chile. There is also a considerable time difference between the places which helps to supply electric energy via solar power even while it is night in China.

Honestly it's kinda brilliant. With a big enough global network of overbuilt solar capacity you would avoid the problems of the duck curve and weather limitations.

It's hard to build an actual network out of DC power, which is partially why AC power took over.

It was hard to build a DC network in 1900. It's easy today with modern power electronics, which Nikola Tesla didn't have. In fact building a DC network is somewhat easier than AC now because phase-matching is unnecessary.

Looks like DC power is more efficient for long haul cables.

https://engineering.stackexchange.com/a/19759

That's a good link.

Summary: DC is always a bit more efficient than AC. The reason our grid is AC is because high voltage transmission is much more efficient than low voltage transmission.* But you don't want multi-thousand volt feeds coming into your house, so voltage conversion is necessary. If you don't have power electronics, you have to use magnetic transformers to convert between voltages, and magnetic transformers only work on AC. Thus our electric grid is mostly AC.

Now that we have power electronics we can convert voltages without magnetic transformers, and AC is no longer a requirement except for backward compatibility.

*unless you have superconducting cables

Presumably it would be very useful to China to be able to buy power during their night time. It might also be beneficial to Chile to be able to buy power from China when the situation is reversed. Better interconnections mean you can get more benefit from cheap solar and don't have to rely on batteries.

Dammit, the sun is my battery! and the earth's tilt, spin and orbit is my load balancer!

I was immediately thinking about early morning in Asia, still dark outside, everybody puts the kettle on.

If these long distance cables really can transport energy efficiently it might solve some of the challenges with renewables!

> I was immediately thinking about early morning in Asia, still dark outside, everybody puts the kettle on.

In the UK they actually have to plan for grid demand to skyrocket during ad breaks in certain TV shows because half the country puts the kettle on at the same time! In one episode of EastEnders, demand grew by 2290MW, nearly twice as large as any single UK nuclear reactor.

https://www.mylondon.news/news/zone-1-news/iconic-eastenders...

The UK have 3000W kettles whereas in North America is stuck with 1500W kettles.

Many kitchens in North America have 20A outlets, which should at least let us use 2000W kettles. Why won't anybody sell me a 115V/16A kettle with a NEMA 5-20 connector?

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