UK’s DESNZ Electricity Supply Emergency Code prioritises maintaining power for Protected Sites, such as hospitals, airports, and water treatment facilities, during emergencies. These sites are already major energy users, with a large proportion of this demand currently hidden from DNOs through onsite fossil fuel generation. AS PS move away from fossil fuels, their energy demands from the grid will only increase.
PSs’ diverse resilience needs, from critical care to administrative buildings, necessitate innovative heat flexibility strategies. Current systems rely on carbon-intensive backup solutions; without coordinated decarbonisation planning between Protected Sites and electricity networks, the counterfactual is significant, uncoordinated investment in the electricity networks.
Due to their significant and varied heat demands, FORTRESS is using hospitals as a first case study. There is no clear solution to delivering decarbonisation for these sites. Electrification of heat will be investigated. Replacing hospital heating appliances with electrified technology will require greater DNO capacity, and scaling this across 200 large hospitals in Great Britain highlights the size of the decarbonisation challenge.
FORTRESS will conduct extensive stakeholder engagement for our first case study site, NHS Tayside, and will gather site energy data and identify critical needs which must be considered within the context of resilience and flexibility.
Key Discovery outputs include an assessment of future changes which impacts the electricity network and Protected Sites, an understanding of the business case for PSs energy flexibility, a summary of key decarbonisation pathways based on real site data and an assessment of network impacts and benefits.
Currently, there is insufficient understanding of the most suitable decarbonisation options for Protected Sites. FORTRESS aims to improve stakeholders’ capabilities to build scenarios with different technologies based on operational data, by producing more knowledge that can be used for future network planning.
Networks Benefits:
Improved decision-making through more accurate and updated information on the electrification challenges of Large Protected Sites), in particular for decarbonisation of heat. NHS England data (ERIC) shows that average acute hospital electricity consumption is 7.9GWh compared to 38GWh of gas – suggests significant future electrical demand increases where heat is electrified.
Consideration of whole system solutions when considering critical customer needs (locational options, heat networks, cross-technology approaches to mitigate peak electrification scenarios)
Potential reductions in network investment, due to enhanced network planning from direct coordination and engagement with PSs.
Facilitating the energy transition of the sites from an inflexible demand user to a flexible demand, thereby reducing network constraints and increasing spare capacity headroom.
Energy Consumers Benefits
A more cost-effective approach than “over-engineering” the solution as per BAU reinforcement
Less socialisation of investment in new grid infrastructure to energy consumers through their energy bills. This will align with Ofgem’s policy of providing value for money to energy bill payers.
Protected Sites Benefits:
Adopting innovative planning and operational procedures for PSs with electrified Heat can reduce costs and CO2 compared to BAU
Understand the electricity market revenue streams, network planning mechanisms and whole system solutions for heat decarbonisation leading to an opportunity to create new flexibility revenue streams integrated into a site’s decarbonisation plans
Reflect benefits of interruptible gas supplies to hospitals
Articulate the needs of PSs from electricity markets, to support their electrification investment planning
Greater DNO and PSs’ coordination will lead to more streamlined site planning to enable their decarbonisation plans to be achieved cost-effectively.
FORTRESS was successful in receiving SIF funding in the February rounds of applications. Discovery phase work will start mid-May for three months.
Total Discovery costs: £163,905
SIF Discovery funding requested: £146,524
12th May 2025 – 12th August 2025
