Project Summary
Installation of a new Distribution Network Operator (DNO) intake substation and comprehensive electrical systems to support the hospital’s renewable‑energy and decarbonisation strategy.
Electrical Scope of Works
- DNO intake substation (HV/LV) and connection to National Grid circuits
- Installation of LV switchgear, internal small power circuits, substation heating, dehumidifiers
- Internal lighting infrastructure across patient/service areas
- Full earthing (LV and HV) systems, including lightning protection and over‑pressure relief vents
- Fire alarm integration and containment installation
- New utility power supplies to the substation and provision of substation‑grade earthing
Testing & Commissioning
Comprehensive testing and commissioning performed on LV switchgear, earthing continuity, insulation resistance, pressure testing and protection settings under senior authorized personnel supervision.
Utility Power Systems
Small power systems and substation services installed to power heaters, de‑humidifiers, lighting, fire alarm, lightning protection, and over‑pressure relief systems. Containment systems (cable trays/conduits) installed throughout.
Earthing & Lightning Protection
Separate earthing schemes for HV and LV equipment, including exothermic bonding, lightning rods, bonding to lightning protection and pressure relief vent earthing.
Integrated Services – Electrical Works Summary
| Area | Description |
| Testing | LV switchgear, protection relays, earthing continuity, insulation resistance |
| LV Switchgear & Power | Distribution boards for small power, substation heaters, dehumidifiers |
| Internal Lighting | Low‑energy, high‑efficiency fittings—integrated with emergency lighting |
| Fire Alarm & Lightning Protection | Lighting protection earthing, full fire alarm loop wiring |
| Containment | Cable trays and conduits installed throughout substation and building zones |
| Earthing | Separate HV and LV systems, bonding to substation structure, earth mats, grounding rods |
| Over‑Pressure Relief Vents | Installed with dedicated earthing per safety standard |
| New Supply Delivery | New mains LV feed to substation, interface with DNO’s intake switches |
| HV Earthing | Bonding and grounding for HV switchgear and network equipment |
| Substation Equipment Services | Heaters, de‑humidifiers, lighting powered via new switchgear installed in substation |
Key Technical Challenges
- Phased installation enabled continuous hospital power and compliance with NHS critical care uptime.
- Installation of safe systems of work (SSoW) under CDM regulations, isolation procedures, and DNO-approved switching protocols.
- Integration with wider decarbonisation plan—including solar farm, ASHP plant, and CHP schemes already in place or parallel delivery.
Impact & Strategic Benefits
- Enhanced resilience: Dedicated DNO intake and substation allow better control and flexibility of power flow.
- Future‑proof capacity: Designed to support anticipated growth in hospital electrical load.
- Decarbonisation alignment: Underpins a hospital energy strategy to power the facility largely from renewable solar PV (up to 6–7 MWp)
- Cost savings: Long‑term financial benefit reinvested into patient care (~£1 million/year).
Summary
This project at New Cross Hospital showcases a full‑scale DNO substation installation and electrical infrastructure package, aligned to carbon‑neutral strategy and operational resilience. From HV circuit provision, LV distribution, earthing, testing, containment, internal lighting, to fire and lightning protection systems, the project delivered turnkey utility services to NHS standards, supporting long-term savings and renewable transition goals.
