[distortedsignal]

> The required converter stations are expensive and have limited overload capacity. At smaller transmission distances, the losses in the converter stations may be bigger than in an AC transmission line for the same distance. The cost of the converters may not be offset by reductions in line construction cost and lower line loss.

https://en.wikipedia.org/wiki/High-voltage_direct_current#Di...

Not to mention that circuit breakers are harder in DC.

[dhdc]

> Not to mention that circuit breakers are harder in DC.

[Citation needed]

[elihu]

I can believe this is true. It's easier to make reliable AC switches because whatever arcing you get is self-extinguishing because the voltage passes zero 120 times a second. With DC, if you get an arc it'll just keep going as long as conditions allow. That means if you use a designed-for-AC switch in a DC application with the same voltage, it's likely to destroy itself sooner or later.

(Apparently this is one of the reasons why cars stick with 12V for accessories, because if they used higher voltages the electrical switches would be more expensive and less reliable.)

I don't know how this is normally overcome. In a lot of cases, the solution might just be "use a fuse instead".

[alduin32]

Yes, opening a DC circuit under load can be very surprising. The arcs can just stay on forever, and pose a big fire hazard.

[pfdietz]

A big capacitor?

[distortedsignal]

https://en.wikipedia.org/wiki/High-voltage_direct_current#Hi...