Modern Energy Partners: Practical decarbonisation of UK public sector estate

Modern Energy Partners (MEP) was a ground-breaking £20million innovation pilot exploring how to practically decarbonise the public sector estate to help the government reduce carbon emissions by 50% by 2032.

MEP ran from April 19 to September 21, with Energy Systems Catapult coordinating and delivering the programme and providing analytical and technical expertise, while drawing on cross-industry capabilities and knowledge from Aecom, Atkins, Buro Happold, Ricardo and Stantec amongst others.

MEP was funded by the Energy Innovation Programme from the Department for Business, Energy and Industrial Strategy (BEIS) and delivered findings that complex public sector sites — such as hospitals, prisons, and military barracks — could achieve a 70% reduction in carbon emissions by 2032 with an average capital cost of £12.6m per site.

The Challenge

With more than 300,000 individual properties, at a combined value of £515bn, the UK public sector manages, by some distance, the largest property portfolio in the country. The Central Government estate alone has an estimated value of £157.6bn, with an annual running cost of £21.7bn. Public sector buildings are responsible for around 2% of the total UK greenhouse gas emissions.

While the Government has made good progress in decarbonising its operations – reducing emissions by 57% by 2021-21 compared to 2009-10 and with an estimated 38% of this reduction due to improved management of the estate – there is still more to be done.

The government has pledged to reduce direct carbon emission from public sector buildings by 50% by 2032 and to reduce them by 75% by 2037, both against a 2017 baseline. In its 2017 Clean Growth Strategy, the government committed the public sector to lead by example in reducing emissions.

The Innovation 

The MEP strategy was to develop was a repeatable, systematic and scalable approach, that incorporated whole-systems thinking, to decarbonisation of the public sector estate from individual buildings to large campus sites and whole estate portfolios.

Energy Systems Catapult focused on learning through doing, testing out the practicalities of decarbonisation methodologies directly to sites across the health, prison, and defence sectors.

MEP investigated a test bed of 42 sites responsible for over 4 million tCO2e carbon emissions – equating to 3.2% of Ministry of Defence (MOD), 13% of Ministry of Justice (MOJ), and 3.5% of NHS sites, including three pathfinder sites:

  • HM Sheppey Prison Cluster
  • HMS Collingwood – Royal Navy base
  • NHS Goole and District Hospital

At Goole and District Hospital for example, the MEP innovation pilot developed a decarbonisation plan for the site that demonstrated how a £2.8million investment could decarbonise the site by 66%.

Between March and December 2021, the Hospital implemented a range of measures aimed at reducing its carbon footprint following the MEP recommendations, these included: the removal of existing coal-fired boilers, the installation and integration of a new building management system, and upgrades to the building fabric.

Further demonstrating the value of the MEP methodology, HMS Collingwood the Royal Navy’s largest training establishment and headquarters to the Maritime Warfare School, has reduced its energy usage by 3.8 Gigawatt hours on site (9% of the site’s annual usage). In addition, £530,000 and 560 tCO2e has been saved per annum on the campus.

The final result for MEP, was an innovation solution that did indeed produce scalable, replicable methodologies for the decarbonisation of the public sector estate, which focused on three aspects in particular:

  • Rapid deployment of sub-metering and data analysis;
  • The creation of Concept Designs that offered each site a decarbonisation pathway;
  • Accelerating no-regret measures on site.

Case Studies

HMS Collingwood

HMS Collingwood is the Royal Navy’s largest training establishment and headquarters to the Maritime Warfare School. The site was built in 1940 and has 2,500 personnel on site on any given day. The campus-style site is located on the edge of Fareham in Hampshire.

Over the years, the site has been maintained within the constraints of limited funding for infrastructure projects. Estate management has primarily focused on energy-saving schemes and maintenance contracts that are based solely on reactive ‘fail then fix’ measures.

In 2017, the site had an annual energy consumption of 45,402,057 kW and an estimated energy bill of £2,832,000.

Key facts

  • Timeframe: 6 months
  • Energy efficient internal LED lighting installed in 50 buildings on campus
  • Building Management System installed to optimise heating performance
  • £530,000 and 560 tCO2e saved per annum for the campus
  • A reduction in energy usage of 3.8 Gigawatt hours on site (9% of sites annual usage).

The Solution 

Findings and recommendations from the Modern Energy Partners programme are available in the report – Testing the practicalities of public sector decarbonisation – (available to download below).

The overall conclusion: that for the public sector to meet commitments it must rapidly scale up its decarbonisation activities.

Energy Systems Catapult has refined and sharped learnings from Modern Energy Partners to create the definitive Public Sector Decarbonisation Guidance – with step-by-step guidance, insights, tools, templates, case studies and recorded webinars available launched in early 2023.

Topics covered included:

  • Strategy – management, planning and governance
  • Data – the importance of smart energy data management, including metering/sub-metering, data monitoring and analytics
  • Information Gathering – site visits/maps, baselining/benchmarking and data capture
  • Concept Design – technological options, calculators for different interventions and engineering
  • Energy and Cost Modelling – developing, modelling and writing up solutions, linked to business case development
  • People – skills, capabilities and capacities, supply chains and procurement
  • Costs – financial planning, business cases and funding.

Public Sector Decarbonisation Guidance

Accelerating carbon emissions reduction across public sector buildings, sites and estates… with simplicity, speed & scale

Find out more


MEP worked across a testbed of 42 sites, developing 24 decarbonisation plans that would deliver a 70% emissions reduction for an average of £12.6m per site.

Based on this methodology the Department for Energy Security and Net Zero and the Cabinet Office commissioned the Public Sector Decarbonisation Guidance to help public sector bodies and their decarbonisation partners:

  • Understand the best route to Net Zero
  • Support grant funding applications
  • Deliver decarbonisation projects at scale that enable rapid reduction in carbon emissions.

In recognition of its real-world impact, helping to reduce emissions and make energy savings across the public sector estate, the Modern Energy Partners programme won the award for Best Collaboration at the Government Property Awards 2022.

Award judges said: “MEP was an ambitious collaborative programme. Without the input of the wide rage of stakeholders involved, the programme could not have delivered the impressive range of outputs and impacts.”

Our Sites platform emerged from MEP, allowing Energy Systems Catapult to adapt methodologies to make energy savings and cut emissions across public, commercial or industrial estates with award-winning teamwork, ground-breaking guidance and the latest innovative thinking, including:

  • Decarbonising Public Sector sites
  • Decarbonising Commercial and Industrial sites
  • Driving real-world impact with Data you can depend on.

Figure 1: Modern Energy Partners impact at a glance.

Read the Report

Modern Energy Partners: Testing the practicalities of public sector decarbonisation

Net Zero Sites

We help you to make energy savings and cut emissions across public, commercial or industrial estates with award-winning teamwork, ground-breaking guidance and the latest innovative thinking.

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