NHS Heat Decarbonisation Plans: A Comprehensive Guide

As the world grapples with the escalating climate crisis, the NHS has taken a bold step forward. By the end of March 2024, all NHS Trusts are required to have a Heat Decarbonisation Plan (HDPs) in place. This strategic move is designed to shift from heating systems dependent on fossil fuels to those that favour low carbon alternatives, significantly reducing the NHS’s carbon footprint.

The driving force behind this mandate is the NHS’s pledge to achieve net-zero carbon emissions, an ambitious and necessary goal given our current environmental predicament. HDPs are all-encompassing plans that assess energy usage and heat demand in existing non-domestic buildings, provide a detailed resource outline, and list energy efficiency projects that have been implemented and those planned for the future. The NHS is already making considerable progress towards its targets of reaching net zero for the emissions it controls directly by 2040, and for the emissions it can influence by 2045, by upgrading heating, lighting, and ventilation systems, installing onsite solar panels, and ensuring estates are fully digitally integrated.

Implementing HDPs can yield a plethora of benefits for NHS Trusts. They can drastically reduce carbon emissions by transitioning from fossil fuels to electrically powered heating systems and enhance energy efficiency and security by reducing reliance on imported gas and oil. This transition also offers a strategic advantage in terms of resilience to climate change impacts.

Health benefits are another key aspect, as emission reductions can mitigate potential health implications from climate change and air pollution, which contribute to 1 in 20 deaths in the UK and increase cases of cancer, heart disease, and asthma. (Daly and Moir, 2022) Financially, a well-planned strategy can save millions of pounds in conversion costs for large hospitals and the Public Sector Decarbonisation Scheme (PSDS) run by Salix funds HDP projects to upgrade heating systems in public buildings to cleaner, cheaper, and renewable energy.

An effective heat decarbonisation strategy for NHS Trusts begins with a comprehensive HDP that outlines the organisation’s strategy to reduce its reliance on fossil fuels used for heating. This includes transitioning to electrically powered heating systems and understanding the architectural and infrastructural constraints that need to be overcome.

The plan should also assess the current state of buildings and their energy performance, taking into account factors such as age, building fabric, and design. Recommendations should be made to improve energy efficiency, thereby reducing energy loads and improving efficiencies.

A thorough understanding of existing heating (HVAC systems) is crucial to scope out alternatives. Structural considerations, such as load-bearing capacity, building design, electrical infrastructure, and local electricity grid capacity, must be taken into account to ensure that replacement heating systems are fit for purpose. The plan should also consider the installation of low-carbon alternatives, such as air and ground source heat pumps and explore opportunities to tap into existing district heating systems or partner with local organisations to create a low-carbon district heating scheme. Lastly, funding opportunities, such as the Public Sector Decarbonisation Scheme (PSDS) run by Salix, should be explored to help upgrade heating systems in public buildings.

Decarbonising heat in the legacy and complex estates of the NHS is indeed possible, albeit challenging due to the diversity and intricacy of buildings and heating systems within the NHS estate. Many large hospitals, particularly those constructed over 20 years ago, utilise steam for space and hot water heating, as well as for certain sterilisation and humidification processes. These steam heating systems are typically gas-powered and necessitate the maintenance of high-pressure conditions throughout the network. Hot water and space heating systems alone account for 80% of the NHS’s direct emissions (NHS England and NHS Improvement, 2020).

The NHS Property Services (NHSPS) is considering Power Purchase Agreements and a mixed portfolio of on-site and off-site solutions, including heat pumps, biomass, solar, and hydrogen. However, implementing technologies such as solar power and heat pumps in an ageing estate is particularly challenging, as the condition of existing buildings often restricts the feasibility of installing these alternative heat sources. Furthermore, for hospitals in constant use, a reliable, uninterrupted source of energy is essential. Despite these challenges, the NHS continues to strive towards its goal of decarbonisation.

Educational programmes for staff and awareness campaigns are instrumental in fostering energy conservation habits, promoting mindful energy consumption among healthcare workers. Concurrently, the use of energy-saving devices and intelligent building controls refines heating systems, adapting in real-time to changes in occupancy and climatic conditions. Enhancements to the building, such as improved insulation and the installation of double-glazed windows, help to reduce heat loss and overall heating requirements. Furthermore, embracing renewable energy technologies, such as photovoltaic panels and wind turbines, in conjunction with combined heat and power (CHP) systems, provides eco-friendly alternatives, lessening dependence on conventional heating approaches.

NHS Trusts can also leverage heat recovery solutions, utilising systems that seize and repurpose waste heat. The use of waste heat, together with heat recovery ventilation, optimises energy efficiency within healthcare establishments. The integration of continuous monitoring systems and routine energy audits guarantees perpetual evaluation and modification, calibrating the heating infrastructure for peak performance. By implementing these strategies, NHS Trusts can effectively reduce their demand for heat.

Heat pumps and district heat networks play pivotal roles in the decarbonisation of heating systems.

Heat Pumps

Heat pumps are on track to become a mainstream technology in the NHS and other built environments over the next decade and beyond. They are instrumental in the shift from fossil fuel heating systems to more sustainable alternatives. With the rapid decarbonisation of grid electricity, the installation of a heat pump in NHS facilities can result in 55 – 65% less carbon dioxide emissions than a modern gas boiler. The Carbon Trust forecasts these savings to increase to over 90% as the grid further decarbonises in the coming decades. However, heat pumps are still relatively rare in existing NHS buildings, with only around 20,000 retrofits per year since 2014 (Rivers, 2020).

District Heat Networks

District heat networks, also known as heat networks or district heating, distribute heat from a centralised source to multiple NHS buildings through a series of underground pipes. This eliminates the need for individual, often carbon-intensive, heating systems in NHS facilities. Heat networks can harness heat from a variety of sources, including low or zero carbon sources, thereby reducing the environmental impact of heating. In high-density urban areas where many NHS facilities are located, they often present the most cost-effective, low-carbon heating solution.

The Public Sector Decarbonisation Scheme (PSDS) serves as a critical financial support mechanism for NHS Trusts embarking on the transition to a decarbonised heating infrastructure (Department for Energy Security and Net Zero, 2023). This scheme provides funding opportunities that directly contribute to the implementation of HDPs. As the competitive landscape for funding intensifies, having a robust HDP becomes imperative for NHS Trusts seeking support from programmes like PSDS.

The PSDS offers financial assistance for a range of decarbonisation measures, including the adoption of low-carbon technologies, energy-efficient upgrades, and infrastructure improvements. By aligning their HDPs with the criteria set forth by PSDS, NHS Trusts can enhance their eligibility for funding. This financial support, in turn, facilitates the implementation of identified heat decarbonisation strategies, ensuring a smoother and more expedited transition.

WRM offers environmental and sustainability consultancy services to a variety of sectors and organisations. One of our specialities is carbon consultancy, which involves assisting clients in reducing their carbon emissions and achieving net zero targets. We aid in the development of HDPs that decrease the carbon intensity of heating systems in NHS estates and facilities.

We support our clients in identifying and implementing low carbon heat solutions, such as heat pumps, biomass boilers, district heating networks, and hydrogen. Additionally, we assist clients in accessing funding and incentives for heat decarbonisation projects. Our team of specialist sustainability consultants possess the technical knowledge and experience to deliver effective and customised HDPs for any NHS Trust. Contact us today for a free, no-obligation consultation.

• Daly, F. and Moir, E., 2022. Drive for energy efficient healthcare is delivering for patients and planet. NHS England. Available at: https://www.england.nhs.uk/blog/drive-for-energy-efficient-healthcare-is-delivering-for-patients-and-planet/ [Accessed 12th January 2024].
• Department for Energy Security and Net Zero (2023) Public sector decarbonisation scheme, GOV.UK. Available at: https://www.gov.uk/government/collections/public-sector-decarbonisation-scheme [Accessed: 12th January 2024].
• NHS England and NHS Improvement (2020) Delivering a ‘Net Zero’ National Health Service. [Online]. Available at: Greener NHS » Delivering a net zero NHS (england.nhs.uk) [Accessed: 12th January 2024].
• Rivers, W. 2020. Decarbonising buildings with heat pumps. Built Environment Journal. [Online] Available at: https://ww3.rics.org/uk/en/journals/built-environment-journal/decarbonising-buildings-with-heat-pumps.html [Accessed 12th January 2024]