The Alternative Green Energy Thread

JKenH

Another case demonstrating the high cost of curtailment and it is only going to get worse as wind farm capacity increases.

The staggering cost of renewable subsidies is undermining claims about the benefits of net zero

In Dorenell’s case, accounts show the onshore wind farm was paid for 591,164 megawatt hours (MWh) of power in 2024. Only 297,137 MWh of this was actually exported – suggesting 294,027 MWh, or 49pc, was curtailed.

The wind farm has a CfD with an inflation-linked strike price of £82.50 per MWh in 2012 prices, worth about £112 per MWh in current prices.

But Sam Taylor, a former fund manager who now runs Scottish non-profit These Islands, said the huge amount of curtailment meant Dorenell was effectively paid £227 per MWh for the electricity it actually supplied to the grid last year.

This compares to an average price of £77 per MWh paid to gas-fired power plants during the same period, according to energy consultancy Ember.

https://www.telegraph.co.uk/business/2025/08/29/wind-farm-shows-why-miliband-energy-bill-claims-wrong/

Netexporter

Perhaps if previous governments had addressed the, blindingly obvious, need for storage, to even out intermittency/over-supply, there wouldn't be such a problem.

QrizB

Netexporter said:

Perhaps if previous governments had addressed the, blindingly obvious, need for storage, to even out intermittency/over-supply, there wouldn't be such a problem.

And transmission network capacity, to get the power from the generators in the north to the users in the south.

It's hardly rocket science!

Netexporter

A damning indictment of a public school education.

JKenH

Netexporter said:

Perhaps if previous governments had addressed the, blindingly obvious, need for storage, to even out intermittency/over-supply, there wouldn't be such a problem.

Indeed, I’ve been saying that for years. Perhaps the present incumbents might think about prioritising storage and getting the grid sorted ahead of building any more wind or solar farms. Sadly, upgrading the grid isn’t half as sexy as adding generating capacity. Countries are judged by how much renewables capacity they add, not how effective it is.

China has a similar problem

China's renewable power potential in far-flung provinces is increasingly going unused, official statistics showed on Monday, as the country rushes to build more long-distance transmission and energy storage to bridge the gap.

The curtailment rate for solar power rose to 6.6% in the first half of 2025 from 3.9% in the same period a year earlier while the rate for wind rose to 5.7% from 3%, according to the National New Energy Consumption Monitoring and Early Warning Center.
https://www.reuters.com/sustainability/climate-energy/chinas-renewable-capacity-soars-utilisation-lags-data-show-2025-08-05/

Netexporter

I suppose an inadvertent benefit of the delay is that battery storage prices have reduced hugely. The quick win would be to build grid scale batteries on redundant power station sites, which already have the required grid connection.

NedS

Or lay some huge offshore cables down the east coast of the UK to transmit the power from the point of generation (Scotland and the north) to the point of use (London and the south east).

https://www.nationalgrid.com/the-great-grid-upgrade/eastern-green-link-3-and-4

https://www.nationalgrid.com/the-great-grid-upgrade/eastern-green-link-5

michaels

NedS said:

Or lay some huge offshore cables down the east coast of the UK to transmit the power from the point of generation (Scotland and the north) to the point of use (London and the south east).

https://www.nationalgrid.com/the-great-grid-upgrade/eastern-green-link-3-and-4

https://www.nationalgrid.com/the-great-grid-upgrade/eastern-green-link-5

Surely the time to do that was before a lot of misplaced generation came on line rather than 5 years after?

I think we are only just getting to the point where we have general overcapacity rather than simply regional imbalance so it has been distribution rather than storage that we have been lacking.

debitcardmayhem

michaels said:

NedS said:

Or lay some huge offshore cables down the east coast of the UK to transmit the power from the point of generation (Scotland and the north) to the point of use (London and the south east).

https://www.nationalgrid.com/the-great-grid-upgrade/eastern-green-link-3-and-4

https://www.nationalgrid.com/the-great-grid-upgrade/eastern-green-link-5

Surely the time to do that was before a lot of misplaced generation came on line rather than 5 years after?

I think we are only just getting to the point where we have general overcapacity rather than simply regional imbalance so it has been distribution rather than storage that we have been lacking.

I think we need both, otherwise there is still going to be curtailment

ed110220

JKenH said:

Netexporter said:

Perhaps if previous governments had addressed the, blindingly obvious, need for storage, to even out intermittency/over-supply, there wouldn't be such a problem.

Indeed, I’ve been saying that for years. Perhaps the present incumbents might think about prioritising storage and getting the grid sorted ahead of building any more wind or solar farms. Sadly, upgrading the grid isn’t half as sexy as adding generating capacity. Countries are judged by how much renewables capacity they add, not how effective it is.

China has a similar problem

China's renewable power potential in far-flung provinces is increasingly going unused, official statistics showed on Monday, as the country rushes to build more long-distance transmission and energy storage to bridge the gap.

The curtailment rate for solar power rose to 6.6% in the first half of 2025 from 3.9% in the same period a year earlier while the rate for wind rose to 5.7% from 3%, according to the National New Energy Consumption Monitoring and Early Warning Center.
https://www.reuters.com/sustainability/climate-energy/chinas-renewable-capacity-soars-utilisation-lags-data-show-2025-08-05/

There's no comparison between the UK and China though. If there's curtailment in China it's despite massive transmission upgrades because China's solar and wind roll-out has been so enormous. 5 and 6% are pretty low curtailment rates and probably aren't much to worry about for cheaply produced electricity. China installed 212 GW of solar in the first half of this year. To put that in perspective the second-largest nation for solar capacity – the US – had only installed 178GW, in total, by the end of 2024, while third-ranked India had 98GW. Let that sink in - in half a year China installed more solar than the USA has ever installed!

Britain's grid is basically the same as it was in the late 20th C, apart from the undersea interconnectors; China has built a whole ultra-high voltage transmission system like nothing else in the world in the last 15 years. China has built whole 1000 kV AC grids in that time - the UK and West-Central Europe max out at 400 kV. No other country has more than 765 kV AC. The amount of power that can be transmitted rises dramatically with increasing voltage while losses fall, making transmission over longer distances practical. They've also built or are building at least 27 long distance 800 kV or more DC links, the longest over 3000 km long. 

Check out the Wikipedia page on ultra-high voltage electricity transmission in China
Also Open Infrastructure Map - bright blue is >750 kV AC, dark blue is HVDC/UHVDC. It's open source and users only seem to add lines once they appear in publicly available satellite imagery so many of the lines listed on Wikipedia don't even appear yet - again showing how quickly things are moving.

I don't read Mandarin but looking at translated Chinese media they seem to make quite a big thing of these schemes, boasting of how much electricity will be transmitted, the biggest in the world, the highest altitude installation etc.


1000 kV AC double circuit. The description says the towers are 100 m tall - the typical 400 kV pylons in the UK are less than 50 m tall, so would probably fit under the lowest arms of this giant.


Building the  Zhumadian-Wuhan 1000 kV double circuit line in 2023 - Photo Wang Cunfang Global Times