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codersfocusyesterday at 6:38 PM7 repliesview on HN

Does anyone know whether it makes sense to setup solar arrays closer to users or to concentrate them in sunny places and send them throughout the country?

e.g. an analysis of whether we should setup all the solar farms in Nevada for the whole country... set them up in the general south and transmit north... or will each state have their own farms?


Replies

ericdyesterday at 6:58 PM

Distributed. New transmission lines have big nimby issues, and many existing corridors are already getting overloaded. There are recurring attempts to reform the permitting process (in the last Congress it was called EPRA/energy permitting reform act), but… we’ll see.

Bureaucracy is the main thing holding back clean energy right now, rather than economics. You can see this in how Texas, which has lax grid regulation but isn’t biased towards clean energy has far surpassed CA, which subsidizes and got a big head start, in wind/solar generation in a few years.

estimator7292yesterday at 6:52 PM

We don't put all our coal and gas plants out in the desert, they're next to and within our cities.

Physically transporting electricity across distance is very expensive and a not-insignificant amount of power is simply lost on the way. These problems only get worse as the amount of power goes up, and the danger grows very quickly as power goes up. Plus the strategic and logistical benefits of distributed generation.

Simply put you can't centralize generation for the entire country. There's no practical way to actually transport that much power. Not with the technology we have today. If we had high-temperature superconductors then it would make more sense. But with standard metal wires, it's not happening.

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grensleyyesterday at 7:59 PM

The transmission network is underbuilt, so it's mostly best to generate closer to where it's consumed (especially for data centers).

We'll continue to see a mix though of Residential / Commercial & Industrial / Utility Scale

There are about 7,000 Utility scale sites in the US right now, so even the big boys there are fairly distributed.

wrsh07yesterday at 7:01 PM

Casey Handmer is a huge solar bull and his estimate is that solar becomes cheaper than any other form of electricity even when generated from northern states by 2030 (likely sooner)

Iirc solar is meaningfully more efficient (30-50%) in southern states, so it will likely make sense to place energy intensive workloads in locations with more direct sun.

However, the cost of transmitting additional power is interesting and complex. Building out the grid (which runs close to capacity by some metric^) is expensive: transmission lines, transformers or substations, and acquiring land is obvious stuff. Plus the overhead of administration which is significant.

So there's a lot of new behind-the-meter generation (ie electricity that never touches the grid)^^

With all that in mind, I expect energy intensive things will move south (if they have no other constraints. Eg cooling for data centers might be cheaper in northern climes. Some processing will make sense close to where materials are available) But a significant amount of new solar will still be used in northern states because it's going to be extremely cheap to build additional capacity. Especially capacity that is behind-the-meter.

^ but not others! Eg if you're willing to discuss tradeoffs you might find dozens of gw available most of the time https://www.hyperdimensional.co/p/out-of-thin-air

^^ patio11 has a good podcast about this https://www.complexsystemspodcast.com/episodes/the-ai-energy... Disclaimer: my employer apparently sponsored that episode

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lukanyesterday at 8:45 PM

If you would have a high voltage DC transmission line already, linking the dessert and the clouded cities far away, then it makes sense. I think it is worth building them, but it is a big investment. Many lines are proposed, some already build, but with the current US administration I don't think it is a priority.

So decentral is the current way to go.

That is the current state in the US

https://en.wikipedia.org/wiki/List_of_HVDC_projects#/map/3

hn_throwaway_99yesterday at 6:42 PM

High voltage transmission lines are really quite efficient, and concentrating generation is usually the right choice.

That said, it doesn't make sense to have just a single place for the entire country, as there are multiple grids in the US (primarily East, West, and Texas), and with very long transmission you can get into phase issues.

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aaronblohowiakyesterday at 6:54 PM

technically or politically?

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