High-voltage direct current

In the UK with the AST scheme, which is the Accelerated Strategic Transmission Scheme, the regulator has given companies enough visibility that we've been able to go sign up with our supply chain framework agreements.

Just today, Sumitomo is going to be inaugurating a new factory for HVDC in Scotland.

So again, these are examples of the European supply chain also rising up.

to the challenge.

So how do we fix the bottleneck? Do we have to rip up the whole grid?

The technological solution you will likely be adding to your notes is HVDC, high voltage direct current.

Wait, Edison's Revenge? We are going back to direct current?

We are.

And because direct current flows continuously in one direction, it doesn't suffer from the skin effect or the oscillation losses of AC.

Exactly.

HVDC lines can move gigawatts of power across thousands of miles with very little loss.

Wow.

So Grid United, we're an independent transmission development company.

We primarily focus on long distance HVDC interregional transmission, connecting the seams, the different grids, so the western and eastern interconnections.

We have not done a very good job in this country of building those connections.

And as we focus on extreme weather events, reliability, resiliency, these exact type of connections between seams become very compelling and valuable.

And demand is growing extremely fast, and the rules were created for kind of a grid of the past.

So as we evolve, as the grid operators needs evolve, there's a need to re-examine what types of resources receive this accredited capacity.

And HVDC transmission in particular and the resources that are enabled, the power that's able to flow over these lines delivers real tangible capacity benefits to regions, particularly over long distances as you have uncorrelated load and generation profiles.

right so just to be clear about that then if you are a grid operator then you're looking for capacity to as you say make sure you can keep the lights on and you would uh calculate that on the basis of generation resources that are available to you and you'll have a certain capacity value for gas and one for coal and one for solar and wind and so on But you're saying you don't get any benefit at all or you don't kind of record any benefit at all from having transmission capacity running into your grid?

And that's why all the record-breaking Megalinks like the 3000km monsters in China that carry gigawatts across deserts and mountains, all transmit in DC, not AC.

The Changi-Guchuan project that I looked at in my original video remains the world's longest and most powerful UHVDC transmission line.

It's rated at 1100 kilovolts with a maximum carrying capacity of 12 gigawatts.

That's roughly equivalent to the generating capacity of the entire electricity grid of a country the size of Ireland, down a single transmission line.

The Chinese government reckons the project will lead to a further $14 billion worth of investment in secondary power equipment and the wider industrial chain, creating more than 100,000 jobs.

By 2050, the plan is for more than 10 HVDC and new HVDC power corridors to be coming out of the Tibetan plateau, exporting more than 500 billion kWh of electricity every year.

UHVDC systems like this show what's technically possible at continental scale.

But the engineering challenges are enormous.

Now, grids are a problem.

Five-year lead times on transformers, four-year lead times on HVDC cables.

China is dominating on supply chains, on pretty much everything, solar batteries and so on.

So there's a lot to be done.

If we are to bring industry back in the UK and Europe, there's a lot of work.

But we never said it was easy.

I was just recently in Niig, in the Highlands, at a ceremony involving Saki, I didn't drink any myself, I was driving, but we were at the launch of the first HVDC manufacturing facility, I think, established in the UK.

And as Douglas Alexander pointed out, this now brings the UK slightly in line with the rest of the G7 in terms of HVDC manufacturing capabilities.

And the main reason for that is the cost of converting hydroelectricity in Labrador.

So Mercer explained that large-scale hydroelectricity dams produce high-voltage direct current power, or HVDC, which he said is great for transmitting electricity over long distances, like from Churchill Falls to St. John's.

But to use this power inside your house, it has to be converted and stepped down from HVDC to AC or alternating current.

And to do that, you need infrastructure like substation transformers, and you'd also need to install transmission lines.

So here's Nick Mercer explaining more about that now.