UK’s ‘hidden’ power stations to ease stressed grid

Flexibility of 2,000+ CHP plants could make space for more green power.

A heating system already used across the UK has the potential to boost the amount of power generated by renewable sources – and even partly replace fossil fuel power stations.

Combined heat and power plants – which produce both heat and electricity from a single source – are becoming more common as organisations look to cut costs and their carbon footprint.

Latest figures show there are already 2,102 CHP plants in the UK, with a combined maximum electricity generation of 19,900GWh per annum – enough to power more than 4.8 million average UK households.

Those plants also generate heat - enough each year to warm 3.8 million average UK households (around 14 per cent of the UK total).

Many of these systems can turn up or down as the amount of electricity produced by renewables like wind and solar changes, creating room for more green power on the grid.

Now, Edinburgh–based Flexitricity, the UK’s largest demand response aggregator, has plans to harness that hidden potential and help drive a renewable revolution.

Dr Alastair Martin, founder and Chief Strategy Officer, said: “Combined Heat and Power (CHP) systems have an important role to play in a modern decentralised energy system.

“These systems are remarkably flexible and are often not used to maximum capacity, meaning they are ideally suited to responding at short notice to meet shortfalls of energy when the grid needs it without any undue effect on the system as a whole.

“Where a CHP system is running most of the time, it can back off when there’s a lot of wind or solar energy around and keep homes warm using its heat store. This makes CHP the perfect partner for renewable energy.

“So not only can CHP provide cheaper heat and power for households, it can in fact play a significant role in enhancing the security of supply throughout the UK. This is especially the case when users participate in demand response and help to keep the UK’s lights on by adjusting demand or generation when the grid is under stress.”

One in ten of the UK’s CHP plants uses renewable fuel, with the majority (71%) being powered by natural gas.

Stephanie Clark, Policy Manager at Scottish Renewables, commented: “Our energy system is undergoing a fundamental shift as we move away from fossil fuels to tackle climate change.

“In the past, large power stations close to centres of population provided our electricity. But that’s changing: renewable sources provided 24.6% of the electricity generated in the UK in 2015.

“As the supply from those wind, hydro, solar and other generators fluctuates, the grid of the future will flex to accommodate their energy in the most efficient way possible. CHP, along with energy storage and measures like demand-side response, could present a part of that solution.”

Tim Rotheray, director at the Association for Decentralised Energy (ADE), added: “Flexible combined heat and power tackles all three parts of the energy challenge: they are secure, affordable and low carbon. And beyond this CHP plants make a real difference to the competitiveness of British businesses from heavy industry to leisure centres.

“By adding in flexibility, CHP plant can bring greater value to the energy user and help control the cost of the energy system to all consumers.

“Many businesses have untapped value in their CHP plant and others have yet to take up the CHP opportunity. This technology is already cutting waste and cost across the economy and will become more important as the energy landscape changes.”

Dr Martin concluded: “We haven’t even scratched the surface of the potential CHP offers. These systems are becoming more popular as the benefits of moving to localised district heating systems become more widely recognised.

“So while significant potential exists now, this could be even greater in future. Now is the ideal time for owners of CHP systems to investigate how they can harness the true potential it offers.”


Thameswey Central Milton Keynes case study

Thameswey Central Milton Keynes (TCMK) was set up in 2005 to build and operate a low carbon combined heat and power (CHP) energy station.

Thameswey has been reliably providing reserve energy to National Grid through Flexitricity since 2011. Along with providing Short-Term Operating Reserve (STOR) and triad management, Thameswey has played a key role in supporting Western Power Distribution (WPD) with Project FALCON.

Using two gas CHP engines which can be made available to Flexitricity when not required for local generation, Thameswey is able to provide 6MW of generating capacity to help support National Grid during times of system stress and to support the transmission system during winter peaks. This provides Thameswey with an additional revenue stream of more than £100,000 per annum.

Sean Rendall, Operations Manager at Thameswey Central Milton Keynes commented: “The entire process has been flawless from start to finish, with no interference on our core business activities. It provides a valuable source of revenue, and has enabled Thameswey to play its part in contributing greener reserve power supplies to the Grid.”


Issued by Weber Shandwick on behalf of Flexitricity.

For more information please contact:

Steven Flanagan: 0141 333 0557/ 07557 210989/

Notes to Editors

About Flexitricity

Flexitricity partners with businesses throughout the UK to provide reserve electricity to National Grid.

The word “Flexitricity” means “Flexible Electricity”. The company looks for flexibility in electricity consumption and generation, creating revenue for energy users and generators using the flexibility they find.

Flexitricity was founded in 2004 by Dr Alastair Martin, a professional energy engineer with experience ranging from gigawatt-scale coal and nuclear power stations.

Based in Edinburgh, the company introduced the concept of aggregated load management and flexible generation.

National Grid’s estimate of savings to consumers can be found at:

The ADE is the leading decentralised energy advocate, focused on creating a more cost effective, efficient and user-orientated energy system. For more information visit:

Scottish Renewables is the voice of renewable energy in Scotland and is committed to realising the full economic, social and environmental benefits of renewable energy for Scotland. For more information visit:

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