Too much wind power? Why the UK can't always use all its clean energy

On 18th December 2024, over a calm and unremarkably windy Wednesday evening, the UK’s wind farms quietly set a generation record, reaching a peak output of 22.25 GW - or 70% of national demand - at around 6:30 PM. To many, the timing of this achievement might come as a surprise, especially since just over a week earlier, the country had been battered by Storm Darragh, with extreme weather warnings issued nationwide. Yet, despite winds gusting near 100 mph, wind power production during the storm was unremarkable. While it’s true that turbines sometimes have to be stopped temporarily as the wind gusts above their designed limits, this phenomenon of good renewable energy going to waste isn’t just limited to freak storms. If you’re like us, you might be left wondering: why can’t we fully harness our country’s wild weather?

This event highlights a well-known problem: our inability to effectively harness wind power and distribute electricity where it’s needed remains one of the biggest barriers to the clean energy transition. Our grid was designed for centrally located coal power plants, but renewables are built where they generate the most electricity - and in the case of offshore wind, that’s around 30km out to sea. Because we don’t have the right capacity in the transmission grid to get electricity from where it is generated to where it is needed, we are forced to pay renewable energy generators to stop producing so we don’t overload the grid in areas of high production. Even worse, we then pay gigantic sums to gas peaking plants closer to where electricity is needed to meet demand. So how do we solve this?

We outline three critical investments that the UK - and many other countries - will need to make to integrate the big increases in solar and wind generation that are planned over the coming decades.

1. Upgrade the grid 🔌

By 2050 electricity demand in Britain is expected to double. The government’s plans for a clean electricity system by 2030 make it clear that building out a bigger and more responsive grid is essential to meet that demand, by connecting hotspots of generation with towns and cities. Be that building new lines or upgrading existing ones, the plan calls for constructing twice as much transmission infrastructure by 2030 as we built in the last decade - which means quadrupling our pace of delivery! 

To achieve this, the government is also proposing a series of planning reforms to speed up approvals and ensure that the right projects are built in the right places. And we don’t only need to improve the grid within the country - plans are in place to increase our interconnector capacity with the continent, allowing us to sell electricity when we have surplus supply, and buy it more easily when supply is tight - cutting costs and increasing security of supply.

2. Build new storage 🔋

Solar and wind are variable forms of generation - there will be times when supply from renewable energy sources does not meet demand and also times when there are big surpluses. However, the current lack of grid connected storage - that’s batteries, pumped storage hydropower or other schemes - means we are very reliant on gas power plants to balance demand. And given that reducing our gas consumption is key to achieving a clean power system, this will have to change.

To fix this, the government plans for at least 23 GW of new battery storage capacity by 2030, up from 5 GW today. But while batteries are good for storing electricity for up to two days, we also need to expand long duration energy storage, green hydrogen and other novel solutions - these will allow us to better ride out still, cloudy days where renewables aren’t producing much electricity, without having to resort to gas.

3. Transform how we use electricity 🚀

While building new grid infrastructure and expanding storage capacity is a great way to solve our grid problems, demand flexibility tackles the issue by harnessing the collective power of millions of households and businesses.  

In reality, this might look like charging an electric vehicle or home battery overnight, and generally shifting key devices outside of peak hours or to days with plentiful renewable energy output. Demand flexibility is a hot commodity, and will become more and more important as renewables continue to expand. As a result, the government plans to triple demand flexibility, from 5 GW today to 15 GW by 2030. However, achieving this will require us to empower and reward people who use electricity flexibly - something that is core to our mission.

The value of flexibility could be bolstered even further by the introduction of locational electricity pricing, whereby the cost of electricity in each region reflects the availability of supply: places with a lot of wind or solar power but currently low usage would be charged less, and visa-versa. This could encourage larger electricity consumers - such as data centres - to locate in areas where there is a lot of surplus electricity generation, and could dissuade them from setting up in areas that are highly congested.

Although the government has no concrete plans to introduce this method of pricing electricity just yet, traction is growing - it’s certainly a space to watch.

Conclusion

Upgrading our grid, expanding storage and changing how we use electricity are all key parts of the green energy transition. But while the targets the government has set might seem ambitious, they are actually very feasible - the power truly is in our hands to make the changes needed. What’s more, driving these changes will not only lower emissions but also reduce costs by getting cheap renewable electricity to the people who need it. 

Indeed, with the right investments in infrastructure, technology, and changes in how and when we consume electricity, we can build an electricity system that is more reliable, efficient, and better suited to a renewable future.