Overhead 400kv pylons

SlowBlowin

Hi

I take it the disadvantage is the conversion equipment required to convert the DC back to AC synced to the grid, everything else seems to make HVDC a logical choice.

I still think that the reliance on the grid is the issue, making more power closer to where you need it is the answer, a decentralised power distribution system is so much more secure.

SB

Trick of the Tail

Efficient in that it doesn't require power factor correction, so you can go further without having to surface.

The problem with DC is that at each end you have to have a conversion plant to convert from DC to AC for integration with the national grid. These conversion plants are expensive.

Its cheaper these days to go underground AC, and come up for PFC every 40km or so. Power factor correction isn't particularly expensive.

Carawaystick

Dc is also point to point, where you can tap off ac lines along the way

Sam Russell

Pylons and protests are back in the news - this time the proposed NS inter-connector.

Planning granted before Christmas.

TimeToShine

This interconnector is an absolute must now thanks to Brexit. Don't think the protests will make any difference.

GerardKeating

TimeToShine wrote: »

This interconnector is an absolute must now thanks to Brexit. Don't think the protests will make any difference.

Perhaps my ignorance, but I would have thought BRexit might cast doubt on an Electrical inter connector.

All it needs to for some fool to put tariffs/excise duty/what ever on the import/export of electricity between EU and UK, unless you are talking about one to France

Bray Head

GerardKeating wrote: »

TimeToShine wrote: »

This interconnector is an absolute must now thanks to Brexit. Don't think the protests will make any difference.

Perhaps my ignorance, but I would have thought BRexit might cast doubt on an Electrical inter connector.

All it needs to for some fool to put tariffs/excise duty/what ever on the import/export of electricity between EU and UK, unless you are talking about one to France

Ireland (republic) imported €67m worth of electric current in 2015 and exported €26m.

The tariff regime would want to be spectacular for this on its own to merit an interconnector to France.

Carawaystick

Bray Head wrote: »

Ireland (republic) imported €67m worth of electric current in 2015 and exported €26m.

The tariff regime would want to be spectacular for this on its own to merit an interconnector to France.

Off peak domestic electricity in France in 4c/kWH ex VAT and maybe 7c peak. vs 16 cents peak here
Off peak in France includes 2 hours at lunchtime, as well as overnight.

Wholesale's gotta be much cheaper, so I'd need to see if the 67m euros is the price the imported electrictiy was sold in Ireland for, or the price paid in the UK.

You'ld also need to see if the import export current was to Britain, or stayed in Ireland(the island)

Bray Head

Carawaystick wrote: »

Wholesale's gotta be much cheaper, so I'd need to see if the 67m euros is the price the imported electrictiy was sold in Ireland for, or the price paid in the UK.

The €67m is from the CSO trade statistics so it is wholesale cost.

For info, the market output of the whole electricity and gas sector in Ireland was €5.6bn in 2011 (http://www.cso.ie/px/pxeirestat/Statire/SelectVarVal/Define.asp?maintable=OVA04&PLanguage=0). Of this €2.5bn was 'intermediate consumption', mainly raw energy products but also imported electric current.

As you can see the trade in electric current is not huge in the scheme of things, although there are probably less tangible benefits from interconnection such as greater stability in the grid and the ability to balance outages across regions.