At non-negligible losses. (Expected about 10% for the whole system.) Not to mention maintenance of such long cable will be real hard, so redundancy is needed. (For comparison, check costs on much easier and cheaper transatlantic fibre cables.) And of course a facility placed further of the shore is harder to maintain as well.

10% is practically negligible when the power is coming from cheap wind power on the plains.

The 1200 mile Xiangjiaba–Shanghai HVDC line in China has transmission losses "well under 7%" [1]. This line was also completed almost three years ahead of schedule, which is an excellent contrast to Western nuclear plants that are being constructed in China. But then, nobody knows how to complete the AP1000 or EPR on time or on budget, as far as I can tell.

Lots of HVDC lines are going to be essential for cheap power in the US in the future, I just hope the political will materializes for that.

[1] http://3phasepower.blogspot.com/2010/08/xiangjiaba-shanghai-...

Edit: corrected the nuclear comparison.

> EPR on time or on budget

Sure, on one hand, this kind of project is likely to get into cost overruns. On the other hand, Areva looks like a fairly dysfunctional company following the tenure of Anne Lauvergeon, so it's not only a technical problem.

It's also the AP1000 from Westinghouse, not just Areva. There are definitely deep problems at the senior management level down to project management down to QA on welds with Westinghouse. I haven't followed Areva.

At least for the EPR they are building in Finland, AFAIU a lot of the delays and subsequent cost overruns have been due to stuff like poor welds or poorly done concrete that has to be redone. Really basic stuff that one would assume that a company that is building a nuclear power plant could handle, but, alas, apparently not. Of course, Areva is claiming that it's just the Finnish nuclear safety inspectors who are being overly nitpicky.

Yes, nuclear advocates in the US love to blame regulators and ignore the incompetency of their own industry too. There's a new report out today highlighting that at the South Carolina project that was just cancelled, there was an internal report highlighting lack of plans, unconstructable plans, low morale, and high turnover. And that the project was likely to fail. Three months after the report, an additional $800M was requested, and then 18 months later it was cancelled.

http://www.postandcourier.com/news/newly-released-report-hig...

Such behavior seems to be borderline criminal, particularly covering up the internal audit.

Yet this is par for the course on nuclear these days.

A lot of our problems are technically solvable with very near term technology. Yet we choose not to do it.

Not sure what you're getting at, apart from the loss the same disadvantages also apply if the cable is superconducting.

Even worse, maintenance and running costs of superconducting cables are likely much higher due to the cooling (high temperature superconductors are "high temperature" in comparison to other superconductors - there's still lots of cooling needed).

This is a problem that--well, I'm not going to say it's solved, but it's certainly addressed in an ongoing way. In the NE you have a lot of dinky little power plants burning coal and whatever else, but if you look at the NW there's huge hydroelectric. Hydro has to be located where it made sense to build dams; this hasn't always matched up with the needs of the grid. Long distance transmission is thus an ongoing reality. Power from Bonneville goes out to Montana today; it's not hard to imagine the reverse.

Just to add some data to this comment, WECC's "State of the Interconnection" (The line you're talking about is "Path 8"): https://www.wecc.biz/epubs/StateOfTheInterconnection/Pages/T...

Transmission is a solved problem, as far as regional power is concerned.

> "Not to mention maintenance of such long cable will be real hard"

Not really. You'd have to do periodic helicopter patrols of the lines themselves. There isn't really that much "maintenance" that occurs on the line, definitely on the xfmrs/rectifiers/inverters though, but that is normal for any transmission/substation owner.

Also, expected losses are ~5%

So you could lay a power cable across the Atlantic?

It might be physically viable, but I imagine that wouldn't be economically viable.

You responded to someone talking about laying a cable across land. So, no, they did not say that you could cheaply lay a cable across the Atlantic.