4 ms·
Why in the world would they invest into such HVDC project when they already have a huge synchronous grid (unlike the US and Canada, which have 5 grids in total)
by fuoqi 4y ago
Why in the world would they invest into such HVDC project when they already have a huge synchronous grid (unlike the US and Canada, which have 5 grids in total) shared by other countries, especially on the southern border. I think there are even plans for Iran to join this grid. They have absolutely no trouble sending energy across their territory to smooth consumption peaks. Add to that abundance of coal/gas/oil (FYI during winters they use thermal power stations to generate both electricity and heat for homes), robust atomic and hydroelectric generation, and almost zero (in relative terms) solar generation.
They only need relatively short HVDC links to be able to send energy from their hydroelectric installations in Siberia to China and maybe to South Korea and Japan, though with the current geopolitical climate the latter is quite unlikely.
- kzrdude 4y agoHVDCs are increasingly being used inside grids too. Any grid needs high capacity links (AC or DC) to connect its far corners.
- Gare 4y agoHVDC line is cheaper to build and has fewer losses. But you need conversion stations which are expensive and also have some loss. At some distance, HVDC trumps AC even inside synchronized grid. Breakeven point is about 600 km for overhead lines and just 50 km for submarine cables.
- myself248 4y agoAnd that breakeven point keeps getting shorter as the conversion equipment gets cheaper. It used to be much longer, back when the concept was new. Solar already generates DC and inverts to the grid, so tying it directly to HVDC could probably be done by just changing the inverters, rather than adding a whole standalone conversion station. So that makes it cheaper still. The next frontier will be when a customer asks for DC handoff.
- hulitu 4y ago> HVDC line is cheaper to build and has fewer losses. But you need conversion stations which are expensive and also have some loss. I see this argument a lot lately. I fail to see why DC will be better when, at the end, you have to convert it in AC.
- jacquesm 4y agoIn a nutshell: economics. And if two grids are not in sync then you don't have many other options.
- michael1999 4y agoAC loses more energy via ground coupling.
- Gibbon1 4y agoAlso suspect the losses for high voltage AC/DC conversion is very low. As losses tend to depend on current rather than voltage. Not exactly true because you need to connect switches in series to handle the voltage.