Recent figures have highlighted a significant challenge in the UK’s energy system: curtailment costs. Wind-farm operators in Scotland have received more than £205 million this year to turn off their turbines. These payments, or curtailment costs, happen when the electricity generated from wind turbines cannot be fully utilised due to limited demand or grid capacity constraints. These costs underscore two major points. Firstly, the incredible growth and potential of renewable energy in the UK. Secondly the urgent need to overhaul our energy system to accommodate this progress. To prevent this energy waste and unnecessary costs, we must update the grid and, most importantly, deploy energy storage technology.
Renewable Intermittency
Wind energy plays a key role in the UK’s clean energy strategy, providing a significant portion of our renewable power. The increasing number of wind farms across Scotland and the rest of the UK demonstrates the nation’s commitment to reducing carbon emissions and transitioning to a greener energy future. However, the variability of wind power – its generation depending on weather conditions – presents unique challenges. When the wind blows strongly, wind farms can produce more electricity than the grid can immediately handle or than is needed at that moment. Also, the wind doesn’t always blow where the power is needed, creating a surplus, and further complications in energy transport.
Solving Curtailment Costs
Energy storage is crucial in tackling renewable intermittency, and as a result, solving the curtailment problem. By investing in large-scale, long-duration energy storage solutions, we can store excess energy generated during periods of low demand and release it when demand is higher. This strategy not only eliminates the need for curtailment payments but also helps balancing supply and demand within the energy system. It makes the grid more stable and resilient and is also more economical. Long-duration energy storage technologies, such as Storelectric’s Green CAES model, offers a promising solution, allowing us to store massive amounts of wind energy efficiently and dispatch it when needed most.
It’s important to recognise that curtailment is not a flaw of renewable energy. Instead, it shows our grid infrastructure needs to catch up with the rapid deployment of renewable capacity. The UK is on the cusp of a renewable revolution; only by adapting our energy system to these changes can we reap the financial and environmental benefits of clean power. Deploying a holistic energy storage system with varying capacity and duration is a key step in this adaptation process.
New grid infrastructure, like the recently approved subsea energy transmission cable (which will transport renewable energy between Scotland and England), is a necessary. Whilst grid upgrades are a first step in enhancing connectivity and reducing some curtailment costs, they would work best in conjunction with increased storage capacity. Energy storage provides a flexible, scalable, and more economical way to manage the variability of renewable energy sources.
The Economic Case for Energy Storage
By focusing on energy storage, we can maximise the value of every megawatt produced by wind farms and renewables. This will reduce costs for consumers and ensure a stable and reliable electricity supply. It also helps avoid curtailment payments and creates a more efficient, integrated energy system. This approach harnesses the full potential of renewables to cut emissions and lower consumer costs.
A study by Imperial College London revealed that implementing medium-duration energy storage (10-100 hours) could significantly reduce the costs of reaching net zero. They project that energy storage could save the UK between £500 million and £3.5 billion per year, with greater annual savings the sooner storage is implemented. The report also shows that energy storage could increase our wind capacity by 11 TWh per year, without any curtailment costs. See the graph below to visualise these savings.
Embracing energy storage not only promises substantial financial savings but enables the UK to have secure, dispatchable power without having to rely on fossil fuels.
So what comes next?
Transitioning to a greener future involves more than just adding renewable energy. It also requires investing in the right infrastructure and technology to support it. Storage is vital in Britain’s energy transition. It offers a pathway to fully utilise our renewable resources, reduce wasted energy, and keep energy costs down for everyone.
While wind energy’s growth has introduced some challenges, its benefits in combating climate change far outweigh these issues. The solution to curtailment is targeted investments in energy storage and grid modernisation. This will help us harness all the clean, renewable power the UK can generate without incurring unnecessary costs.
