Associate Feature: A local answer to the global climate question

As world leaders arrive in Glasgow for COP 26, how governments balance the need to develop and grow their economies while meeting their carbon reduction targets is at the very centre of the climate debate. In Paris six years ago, the world agreed on the need to reduce emissions to slow the pace of the planet’s warming, but how we do so is still an unsettled debate.

Here in the UK we have an ambitious target to achieve net zero emissions by 2050, and the Scottish Government has its own faster 2045 target. To make these targets a reality will require huge changes to how business and industry currently operates, but it will also mean changes for every household in Britain.

Achieving net zero will mean altering how we heat our homes and what type of cars we drive. No corner of society or sector of industry will be left untouched. It is increasingly clear we are entering a period of transformation that we have not seen on a similar scale since perhaps the industrial revolution.

That earlier revolution first sprung here in the UK and flowed outwards around the world, transforming how industry operated and creating a new economic model. As we stand on the precipice of this new green industrial revolution, the UK has once again the opportunity to lead the world in a period of great change. To do so requires investing in the infrastructure needed to support net zero now before it is too late.  

The search for solutions is a global one, but attendees at COP 26 have one just a two-hour drive from where they are meeting in Glasgow. Drax’s Cruachan Power Station is an underground pumped storage hydro facility built inside a hollowed-out cavern, 1km inside the mighty Ben Cruachan mountain. The plant’s reversible turbines pump water from Loch Awe to an upper reservoir on the mountainside to store excess power from the grid. The stored water is then released back through the turbines to generate power quickly and reliably when demand increases.

This means the ‘Hollow Mountain’ acts like a giant water battery, storing power and then generating it fast when the country needs it most – ideally suited to the changes a net zero society will bring. Electrifying our cars and homes will reshape how our power grid operates. Traditionally demand for power follows a rather predictable pattern of rising usage through the working day falling to a flat, lower rate through the night into the early hours of the next morning. If we all plug in our electric cars after returning home from work or set our heat pumps to warm our homes before waking up, that pattern will be a thing of the past.

Achieving net zero will require our power grid to be more responsive and flexible, exactly what pumped storage delivers. While this might sound like an emerging technology, it is actually decades old. This tried and tested storage system can store more power than lithium battery developed in recent years.

Across April last year, Cruachan’s four units shifted operating modes 969 times as they moved from pumping to generating or spinning to provide stabilising inertia to the grid to manage the changes to demand brought by the first Covid-19 lockdown. The lockdown acted like a net zero trial run for the grid’s operators as the managed fluctuating demand and simultaneously high levels of renewable generation from wind and solar power.

It was a window into the energy system of the future. While the lights stayed on this time, the system became more difficult to manage, which also led to more expensive energy for consumers. As we work towards achieving our climate targets, we need to invest in the infrastructure to enable it.

Drax is progressing plans to build a new, additional underground power station inside the Cruachan complex to more than double its current generating capacity. It would be the first newly built pumped storage power station in a generation – ensuring Cruachan can pave the way for more renewables to help the country meet its climate goals.

The project would be one of the largest infrastructure projects in Scotland in recent decades, creating jobs and bringing much needed investment to Argyll.

The new power station would be built within a new, hollowed-out cavern which would be large enough to fit Big Ben on its side, to the east of Drax’s existing facility. More than a million tonnes of rock would be excavated to create the cavern and other parts of the power station. The existing upper reservoir, which can hold 2.4 billion gallons of water, has the capacity to serve both power stations.

Acting like a battery, Cruachan soaks up excess power from wind farms when generation is not in sync with supply, stopping renewable energy from going to waste. While the UK’s policy and market support mechanisms have evolved to support new build renewables, the current framework isn’t suitable for pumped storage projects that can have a lifespan of many decades. Indeed, no new pumped storage plants have been built anywhere in the UK since 1984.

By not supporting the creation of a new generation of pumped storage plants, the UK would risk making the journey towards net zero more difficult and ultimately more expensive for consumers. An independent report by academics from Imperial College London recently found that just 4.5GW of new pumped hydro storage could save up to £690m per year in energy system costs by 2050.In July, the UK government issued a call for evidence from industry on how it could reform the market to support long duration storage technologies. That was a welcome move and a clear signal that pumped storage is beginning to rise in importance for policymakers as they sketch out the path to achieving net zero.

If planning consent is given for the new power station, alongside a suitable market support mechanism, the extra capacity from the new station could be available in 2030.

With the right support framework from the UK Government a new generation of pumped hydro storage power stations can be built, supporting new jobs and helping the country decarbonise faster.

Our world is about to change dramatically, and Drax is ready to lead the way in securing a greener future for the UK.

This article is sponsored by DRAX.