Sector Education

Services Electrical Design & Build

Contract Value £1.2M

Programme 30 weeks


Pentalec were appointed to deliver the electrical services to support the decarbonisation of three primary schools in St Albans as part of the Council’s sustainability initiative and net zero carbon objectives. We worked in partnership with Oakray Property Performance Specialists over a 30-week programme. The project involved the removal of all existing gas heating systems and the installation of a new VRF heat pump system with power provided by roof-mounted solar PV and battery storage systems.


  • Upgrade of LV infrastructure including new incoming main supplies, new panel boards and distribution board upgrades
  • Replacement of all lighting with new energy-efficient LED lighting and lighting controls
  • 290kW Solar PV systems spanning the roofs of each school, with battery storage to capture energy and re-distribute when most needed
  • Single-phase and three-phase power supplies to all new indoor and outdoor mechanical plant equipment
  • New containment systems to support the LV infrastructure and BMS systems



  • Delivered within a live operational school environment
  • Double shifts to deliver the fast-track programme
  • Handling of existing building conditions including assessment of roof for structural integrity relating to the new Solar PV installation
  • Concurrent delivery of all three schools to a fast-track programme



  • Delivered within a live school environment with no health and safety incidents
  • Achieving complicated relocations of main LV supplies and distribution equipment
  • Ensuring zero downtime for the schools during the LV power change overs across several school term breaks

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