The mountain in North Wales that tried to stop the UK’s blackout

Elidir Fawr, the mountain in question. Image: Jem Collins.

Last Friday, the UK’s National Grid turned to mush. Not the official term perhaps, but an accurate one after nearly one million people were left without power across the country, with hundreds more stranded at train stations – or even on trains (which isn’t nearly as fun as it might immediately sound). 

Traffic lights stopped working, back-up power failed in hospitals, and business secretary Andrea Leadsom launched an investigation into exactly what happened. So far though, the long and short of it is that a gas-fired power station in Bedfordshire failed just before 5 o’clock, followed just two minutes later by Hornsea offshore wind farm. 

However, amid the resulting chaos and inevitable search to find someone to blame for the outage, a set of mountains (yes, mountains) in North Wales were working extremely hard to keep the lights on.

From the outside, Elidir Fawr, doesn’t scream power generation. Sitting across from the slightly better known Mount Snowdon, it actually seems quite passive. After all, it is a mountain, and the last slate quarry in the area closed in 1969.

At a push, you’d probably guess the buildings at the base of the mountain were something to do with the area’s industrial past, mostly thanks to the blasting scars on its side, as I did when I first walked past last Saturday. 

But, buried deep into Elidir Fawr is the ability to generate an astounding 1,728 megawatts of electricity – enough to power 2.5 million homes, more than the entire population of the Liverpool region. And the plant is capable of running for five hours.

Dubbed by locals at the ‘Electric Mountain’, Dinorwig Power Station, is made up of 16km of underground tunnels (complete with their own traffic light system), in an excavation which could easily house St Paul’s Cathedral.

Instead, it’s home to six reversible pumps/turbines which are capable of reaching full capacity in just 16 seconds. Which is probably best, as Londoners would miss the view.

‘A Back-Up Facility for The National Grid’

And, just as it often is, the Electric Mountain was called into action on Friday. A spokesperson for First Hydro Company, which owns the generators at Dinorwig, and the slightly smaller Ffestiniog, both in Snowdonia, confirmed that last Friday they’d been asked to start generating by the National Grid.

But just how does a mountain help to ease the effects of a blackout? Or as it’s more regularly used, when there’s a surge in demand for electricity – most commonly when we all pop the kettle on at half-time during the World Cup, scientifically known as TV pick-up.

The answer lies in the lakes at both the top and bottom of Elidir Fawr. Marchlyn Mawr, at the top of the mountain, houses an incredible 7 million tonnes of water, which can be fed down through the mountain to the lake at the bottom, Llyn Peris, generating electricity as it goes.


“Pumped storage technology enables dynamic response electricity production – ofering a critical back-up facility during periods of mismatched supply and demand on the national grid system,” First Hydro Company explains.

The tech works essentially the same way as conventional hydro power – or if you want to be retro, a spruced up waterwheel. When the plant releases water from the upper reservoir, as well as having gravity on their side (the lakes are half a kilometre apart vertically) the water shafts become smaller and smaller, further ramping up the pressure. 

This, in turn, spins the turbines which are linked to the generators, with valves regulating the water flow. Unlike traditional UK power stations, which can take hours to get to full capacity, at Dinorwig it’s a matter of 16 seconds from a cold start, or as little as five if the plant is on standby.

And, designed with the UK’s 50hz frequency in mind, the generator is also built to shut off quickly and avoid overloading the network. Despite the immense water pressure, the valves are able to close off the supply within just 20 seconds. 

At night, the same thing simply happens in reverse, as low-cost, surplus energy from the grid is used to pump the water back up to where it came from, ready for another day of hectic TV scheduling. Or blackouts, take your pick.

Completed in 1984, the power station was the product of a decade of work, and the largest civil engineering project commissioned at the time – and it remains one of Europe’s largest manmade caverns. Not that you’d know it from the outside. And really, if we’ve learned anything from this, it’s that looks can be deceiving, and that mountains can actually be really damn good at making electricity. 

Jem Collins is a digital journalist and editor whose work focuses on human rights, rural stories and careers. She’s the founder and editor of Journo Resources, and you can also find her tweeting @Jem_Collins.

 
 
 
 

Community-powered policies should be at the top of Westminster’s to do list

A generic election picture. Image: Getty.

Over the past five decades, political and economic power has become increasingly concentrated in the UK’s capital. Communities feel ignored or alienated by a politics that feels distant and unrepresentative of their daily experiences.

Since the EU referendum result it has become something of a cliché to talk about how to respond to the sense of powerlessness felt by too many people. The foundations of our economy have been shifted by Brexit, technology and deindustrialisation – and these have shone a light on a growing divergence in views and values across geographies and generations. They are both a symptom and cause of the breakdown of the ties that traditionally brought people together.

As the country goes through seismic changes in its outlook, politics and economy, it is clear that a new way of doing politics is needed. Empowering people to take control over the things that affect their daily lives cannot be done from the top down.

Last week, the Co-operative Party launched our policy platform for the General Election – the ideas and priorities we hope to see at the top of the next Parliament’s to do list. We have been the voice for co-operative values and principles in the places where decisions are made and laws are made. As co-operators, we believe that the principles that lie behind successful co‑operatives – democratic control by customers and workers, and a fair share of the wealth we create together – ought to extend to the wider economy and our society. As Labour’s sister party, we campaign for a government that puts these shared values into practice.

Our policy platform has community power at its heart, because the co-operative movement, founded on shop floors and factory production lines, knows that power should flow from the bottom up. Today, this principle holds strong – decisions are best made by the people impacted the most by them, and services work best when the service users have a voice. Our policy platform is clear: this means shifting power from Whitehall to local government, but it also means looking beyond the town hall. Co-operative approaches are about placing power directly in the hands of people and communities.


There are many great examples of Co-operative councillors and local communities taking the lead on this. Co-operative councils like Oldham and Plymouth have pioneered new working relationships with residents, underpinned by a genuine commitment to working with communities rather than merely doing things to them.

Building a fairer future is, by definition, a bottom-up endeavour. Oldham, Plymouth and examples like the Elephant Project in Greater Manchester, where people with experience of disadvantage are involved in decision-making, or buses in Witney run by Co-operative councillors and the local community – are the building blocks of creating a better politics and a fairer economy.

This thread runs through our work over the last few years on community wealth building too – keeping wealth circulating in local economies through growing the local co-operative sector. Worker-owned businesses thriving at the expense of global corporate giants and private outsourcers. Assets owned by communities – from pubs to post offices to rooftop solar panels.

And it runs through our work in Westminster too – with Co-operative MPs and peers calling for parents, not private business, to own and run nurseries; for the stewards of our countryside to be farmers rather than big landowners; and for workers to have a stake in their workplaces and a share of the profit.

Far from being ignored, as suggested in last week’s article on community power, our work has never been more relevant and our co-operative voice is louder than ever.

Anna Birley is policy offer at the Co-operative party.