Dr Matthew Aylott UKERCBlackouts bring the failure of the electricity network to everyone’s front room in spectacular fashion. During the 1970s blackouts brought a swift end to the Government of Ted Heath. Maggie Thatcher knew the risks associated with blackouts and hoarded coal before taking on the miners in the 1980s.

Put simply keeping the lights on is a political imperative.

To avoid blackouts you need a grid which is capable of meeting fluctuating demands for power.

In the UK for many years this has meant running a large number of ‘baseload’ power stations – mostly coal and nuclear – that run constantly but are slow to respond to changing demand, supported by a smaller number of ‘load following’ and ‘peak’ power stations – mostly gas – that can change output to meet demand or be turned on rapidly to meet spikes in usage.

However, things are changing. The rapid growth and intermittent nature of renewable sources of energy like solar and wind has called for a new way of managing our grid. We require more flexible power to meet the troughs in supply when renewables aren’t generating at full capacity.

In the long-term we are likely to have a smarter grid, with batteries capable of storing energy from renewable power generation and new information and communication technologies (ICTs) like smart meters, which will allow us to better balance supply and demand. But in the short-term as we transition towards a low carbon economy, gas-fired power stations will be necessary to supplement renewable sources of energy.

However, construction of new generating capacity – both fossil and renewable – has been slower than anticipated. This has been blamed on investor uncertainty in the new Electricity Market Reform. In addition, a number of gas-fired power stations have recently been mothballed due to the weak ‘spark price’; the difference between the gas price and the electricity price.

As we reach the so called ‘capacity crunch’ in 2015, when some of Britain’s largest baseload power stations will stop operating due to European emissions regulations [1], many have raised concerns that we are facing a supply shortage which could lead to blackouts.

Ofgem estimate that spare electricity generating capacity could fall from more than 10 per cent today to as little as 1.5 per cent in the winter of 2015/16 and the risk of disconnections could almost quadruple [2]. This remains a worst case scenario and widespread blackouts remain unlikely, nevertheless historically low capacity margins together with a period of cold weather and low wind conditions could create the ‘perfect storm’ for disconnections.

This has prompted action from the Government. Earlier this year Ofgem consulted on plans for a ‘supplemental balancing reserve’ to give the National Grid powers to pay generators to re-open mothballed plant or keep existing power stations operating for longer. However, this would be an expensive option and bringing mothballed plant back into operation takes time.

Another obvious way of avoiding power cuts is to use less energy. Despite the failure of the Green Deal to inspire the nation, improved understanding of energy efficiency in the home and pressure from rising energy bills has already seen domestic gas and electricity consumption in the UK fall by nearly 25% between 2005 and 2011 [4].

Further cuts could be made by rationing electricity or demand side management, where domestic appliances – like fridges – can be switched off externally for short periods when demand spikes. However, this is something UKERC research suggests would be unpopular with the public [3] and needs more effective communication to ensure ‘buy-in’.

Less aggressive strategies could be more successful.

Centrica, owners of British Gas, who supply around 12% of the UK’s electricity, have successfully trialled a system in the US where consumers were offered free electricity on Saturdays to encourage them to do household jobs when demand was lowest. British Gas now intends to roll this out in the UK. But how successful such as scheme would be is uncertain and it would be unrealistic to assume greater energy savings alone will offset shortfalls in supply.

What is needed to keep the lights on is a whole systems approach to our energy system, where policies aimed at both demand and supply work together. The Electricity Market Reform needs to make Britain an attractive proposition for investors and needs to do so quickly. And as UKERC has argued previously, the Electricity Market Reform needs to take demand response and reduction seriously.

Ultimately the capacity crunch won’t cause blackouts, only inaction will.

This article first appeared on BusinessGreen.

Dr Matthew Aylott is Communications Officer at UKERC – but writes here in a personal capacity. He previously worked as a bioenergy researcher for the University of Southampton and for government advisors NNFCC.


[1] European Commission. Large Combustion Plants Directive, November 2001. http://ec.europa.eu/environment/air/pollutants/stationary/lcp/legislation.htm

[2] Ofgem. Electricity Capacity Assessment Report 2013. June 2013. www.ofgem.gov.uk/ofgem-publications/75232/electricity-capacity-assessment-report-2013.pdf

[3] UKERC. Transforming the UK Energy System: Public Values, Attitudes and Acceptability. July 2013. www.ukerc.ac.uk/support/tiki-download_file.php?fileId=3229

[4] ONS. Household Energy Consumption in England and Wales, 2005–11. August 2013. www.ons.gov.uk/ons/rel/regional-trends/area-based-analysis/household-energy-consumption-in-england-and-wales–2005-11/art-household-energy-consumption-in-england-and-wales–2005-11.html