Will the UK Blackout This Winter?

Do you remember the 1970s blackouts? Did you sit in candlelight and make shadow pictures on the wall?

As you may know, the cause of these blackouts were a prolonged period of political unrest and a miner‘s strike. With coal stocks running low, the government put into place a restriction on electricity consumption. This meant three-day weeks for some employers and power cuts for homes. The power cuts were generally scheduled, so you knew when they would occur, and life went on. With only three television channels and no electronic devices (except for the first LED calculator which generated great excitement) — loss of electricity was less of an issue than it would be in today’s gadget packed world.

While you might think that the days of blackouts are long gone, recent headlines in many newspapers suggest that Britain is heading for a dark winter — but what is the truth? The UK couldn’t blackout this winter, could it? Surely the government wouldn’t allow it? Let’s find out!

Supply and Demand

The key to whether blackouts will happen is the notion of the capacity margin. The capacity margin is described by Ofgem as the ‘excess of installed generation over demand’. This is effectively the safety margin that the National Grid and the energy supply companies use to make sure the lights do not go off. A wide margin means the system can cope with sudden increased demand — for example if everyone boils a kettle at half-time in a big football match. A low margin means sudden demands on the system have to be managed more closely and potential spikes in demand prevented. So if we know that the capacity margin is important, surely there is not a problem — just keep a wide margin.

Narrowing margins

There is a potential problem with the supply margin for the next few winters — and the root of the problem is cheap coal. The UK has sufficient power stations to supply all the electricity we need — when they are all running. Gas powered power stations can be turned on and off reasonably quickly, and so are good in winter for when the weather turns cold. However, in recent years the energy companies have been mothballing gas power plants as the price of coal has been reduced, making electricity generated using coal more attractive to the energy companies. In 2010 approximately 28% of our electricity was generated using coal — in 2014 the figure is 38%. But, as the older coal powered generators are being permanently switched off this reduces our capacity.

Lights Out?

So, will the UK blackout this winter? The short answer is no. The energy companies and the government are satisfied that we’ll be OK. And we all know that government officials are always 100% accurate and correct. Box of candles anyone? 

In all seriousness, measures have been taken to ensure the UK supply is maintained — with agreements to keep more gas powered plants ready to fire up if needed. The long-term fix is to reduce our reliance on imported fuels for our energy needs — and that means nuclear, renewables and perhaps even fracking. The likelihood of fracking becoming a main source of energy in the UK is discussed further in this article: Is Fracking the Way Forward?