Investments in the electricity grid are not keeping up with the rapid growth of wind resulting in record losses of green electricity and high costs for British consumers.

In this report, we set out to analyse the health of Great Britain’s electricity transmission grid – the backbone of the future decarbonised power system. We found that, as investments in transmission have stalled, Great Britain’s electricity grid has not kept pace with wind deployment and is currently not fit for purpose. As things stand, the grid cannot adequately deliver the UK Government’s vision of “affordable, homegrown, clean energy”.  

Due to these shortcomings, the system is increasingly forced to curtail wind generation while requesting polluting gas plants to ramp up generation in so-called wind congestion events. Since 2021, wind congestion costs have totalled £1.5 billion, with the amount of wind power curtailed equating to the annual consumption of 1 million households. 

Investments in the electricity grid are not keeping up the pace with the growth of wind capacity, especially, on the critical link connecting the wind resources of Scotland with the large cities and industries of England. Wind capacity in Scotland is expected to grow four times faster than the new transmission infrastructure.  

As a result, we found that wind curtailment on this bottleneck could experience a five-fold increase by 2030, wasting an amount of electricity equivalent to the annual electricity consumption of more than 5 million households. Wind congestion costs across the Scotland-England boundary are set to grow dramatically and could surpass £3.5 billion in 2030. This could result in a nearly £200 increase in annual electricity bills for British households. 



Carbon Tracker Initiative (2023) 

In the report, we present several solutions that could help to solve this problem. First, we focus on the importance of the timely delivery of new transmission capacity and the need to expand the existing pipeline by 2030. Then, we analyse how energy storage and hydrogen can alleviate grid constraints while increasing the resilience of the grid and its capacity to integrate a higher share of renewables. We find that electrolysers and green hydrogen can play an important role in reducing wind curtailment and accelerating the decarbonisation of other carbon-intensive sectors. Finally, we offer recommendations for policymakers to solve wind congestion issues and facilitate the creation of a future-proof electricity grid. 

This report is addressed to policymakers, energy regulators, grid operators, project developers and electricity utilities that can help solve the issue with the electricity grid and reap the benefits of a decarbonised power sector. 

If you have follow-up questions, please contact directly the author Lorenzo Sani at  

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