Pimlico District Heating Undertaking

Pimlico District Heating Undertaking (PDHU) is the UK’s oldest heat network. Operated by Westminster City Council (WCC), it currently serves 3,256 homes, 50 commercial premises and 3 schools. The scheme comprises a heat network served by two 2 MWe gas engine CHPs 24 MWth of gas boilers with economisers and a thermal store.

Silver Expertise

Silver EMS’ technical director, Anthony Riddle has provided engineering services to PDHU for over 10 years. This has included design, techno-economic feasibility of integrating water source heat pumps, hydraulic assessment and condition assessment of existing assets.

The Appointment

Silver EMS was commissioned to carry out hydraulic assessments of the heat network, for two potential scheme extensions involving the connection of new developments in the vicinity, requiring viability assessments under the London Plan.

We have recently received a further appointment by WCC to carry out a techno-economic feasibility study with BSRIA Stage 2 concept design, for installing and connecting a large-scale heat pump into the PDHU heat network.


We have been able to address the requirements of Westminster City Council and GLA to assess the viability of connecting new developments. We maximised the business case for all opportunities, leading to lower cost heat for residents connected to the scheme, addressing fuel poverty.

The scheme has supported a sustainable outcome for the wider community with improved air quality through the reduction of NOx by displaced boiler and CHP operation through connection to an existing network.