James Ball looks at the UK’s energy safety gap and finds we could face a supply crunch as soon as the winter of 2015

There is perhaps no greater nightmare for government and industry than the spectre of blackouts. In the 1970s, rolling power cuts caused by coal strikes led to the three-day working week and the eventual collapse of government. Since then, keeping the lights on has been a priority. But it’s a task that’s getting ever harder, especially amid rising tensions between Europe and Russia, one of the continent’s main oil and gas suppliers.

The task is a daunting one: not only must the UK’s energy suppliers avoid the country ending up as dependent as the European mainland on Russian gas, they must also navigate the challenges of climate change, consumer dissatisfaction at rising bills, and changing government policies on nuclear and other sources.

Last year, just 6% of the UK’s energy generation came from renewable sources, far behind gas, and even coal. The mundane task of making sure homes are light and warm – which requires about 330 terawatts of energy a year – drags in the most complex economic, geopolitical and scientific controversies on the planet.

There’s some good news. Experts from Greenpeace and the “big six” energy providers are united on one thing: the UK should be able to keep the power flowing – for now.

“I think it is implausible that the lights are going to go out anytime soon,” says Dr Doug Parr, chief scientist at Greenpeace UK. “What happens over the next decade is that the ‘supply margin’ gets tighter as coal plants are retired, [though] many nuclear plants will limp on.”

The supply margin is the country’s energy safety gap: how much energy we can generate or access (including from other countries’ energy grids) versus our peak usage. If the gap is large, there’s no problem if we experience a surge in demand. But if it’s narrow, then predicting and preventing spikes in demand becomes very important if we want to keep the lights on.

On the margin: balancing supply and demand

The UK’s supply margin looks good on paper because the country has several gas plants which can be turned on or off relatively quickly. However, because coal is so cheap, the gas plants on which the UK’s energy future relies are not economical to run.

The biggest challenge to the UK’s energy supply margin isn’t years ahead, the data suggests, but very soon indeed – by the winter of 2015-16. The trouble for those managing our power is a combination of factors hit all at once: old generators are being switched off for the last time, gas plants – those best able to plug shortfalls – are being mothballed for the medium to long-term due to the abundance of cheap coal, and the plans for next-generation power production haven’t yet kicked in.

The net result is that the UK’s supply margin, according to forecasts by Ofgem, is predicted to fall from a tight 6% at the peak of winter demand in 2014-15 to a possible low of less than 2% just a year later.

The situation would be much worse if energy use hadn’t fallen so sharply; despite a growing population, peak demand has fallen from about 60GW in 2005-06 to 54GW in 2013-14, and a large portion of that drop happened in the past 12 months. That lower energy requirement is what makes all the difference between the forecast showing the UK just barely keeping the lights on and the prospect of midwinter blackouts.

The UK energy mix

The main risk (though experts agree it’s a small one) is that a combination of stronger-than-expected economic growth coupled with a particularly cold winter could push the country just over the edge.



“The biggest problem for gas in the UK right now isn’t the changing energy mix, it’s dirt-cheap coal,” explains Parr. “Cheap coal is coming into Europe from Russia, Columbia and the US. We probably already have enough gas plants to take up the slack. We definitely have enough if two or three of those in planning are built. But, bizarrely, markets are such that gas plants are closing down or being mothballed.”

Parr’s assessment is echoed by others who are watching the UK’s transition from coal, and one who warns that the risk of blackouts in the near future is higher than it has been for quite some time. Dr Robert Gross, director of the centre for energy policy and technology at Imperial College London, says: “It is very unlikely that the UK will experience power cuts due to inadequate generating capacity. However in the period of 2015-16 the risk of power cuts will be considerably higher than historically, because the UK is closing old coal-fired power stations but has been slow to build new gas-fired power stations.”

Gross says efforts by the National Grid to ensure mothballed gas plants are brought back into service, as well as persuading customers to cut back on their demand for energy, has minimised what could otherwise have been larger risks.

The problem of climate change

Energy reduction schemes range from efforts to insulate homes to paying heavy industrial users to cut back demand at peak times. Needless to say, high energy bills also serve as a good incentive for customers to curb their own use.

Though the UK is largely agreed on moving towards more renewable power to minimise the effects of climate change, opinions are divided on how to do it: should nuclear be part of the mix? Which energy sources should receive government subsidies?

Are onshore windfarms the future of power generation or an eyesore that would blight the countryside? Even if such issues are resolved, there’s a more practical problem: oil and gas is easy to store, but the same can’t be said for the sun or the wind. To shift to renewables, the UK needs a plan for when the sun isn’t shining.

“If we continue to be serious about climate change in the UK, which I think we should be, then it is clear that our energy supplies need to shift fundamentally towards low carbon energy sources,” says Professor Jim Watson, research director of the UK Energy Research Centre. “This is largely an electricity issue, since storing it is very expensive so supply and demand need to be balanced on a minute-by-minute basis. If that means more intermittent renewables like solar and wind and also more inflexible sources of low carbon supply such as nuclear, then gas-fired power … will increasingly be required to balance the system.”

Fixing the problem

The trickier part is trying to work out which renewables to build, Watson adds, given “recent rhetoric from some ministers about the need to limit the use of one of the cheapest technologies – onshore wind – and one of the technologies that has reduced costs most quickly – solar. So energy policy is in a bit of a mess on this point at the moment.”

Much of the burden of fixing that mess lies with a group not currently beloved of the UK public: the big energy companies, whose rising profits attract widespread criticism. However, the companies are aware the ball is firmly in their court. In a public address this year, EDF Energy’s chief executive, Vincent de Rivaz, told the audience: “Among all the issues to be discussed, there are two big ones: first, security of supply, and second, the trust between citizens, customers and our power industry … we have both the responsibility, and the opportunity, to do something about this.”

Ministers, worried about a repeat of the woes of the 1970s, will be hoping he manages it, as will businesses dependent on reliable power. Most households will simply be hoping he can achieve it without higher bills. That may prove the trickiest task of all.

This article is part of the Guardian’s #bigenergydebate series. Click here to find out more about this project and our partners.