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London Underground – Ongoing HV Power & Substation Upgrade Works

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Client:
Power Systems
Sector:
Renewable Energy – Onshore Wind
Voltage Range:
33Kv
Services Provided:
Cable jointing, terminations, testing, QA Documentation
Client:
Transport for London (TfL) / London Underground Ltd
Sector:
Urban Rail / Power Supply Upgrade / Underground Infrastructure
Voltage Range:
LV / 11kV / 22kV / 33kV
Services Provided:
High-voltage and low-voltage cable jointing, terminations, substation upgrade works, confined space delivery, and interface support.

Project Overview

ADY-HV is currently delivering ongoing high-voltage and substation upgrade works across multiple London Underground sites, forming part of the capital’s continued investment in power resilience, capacity growth, and modernisation of legacy infrastructure. Working closely with principal contractors and TfL engineering teams, our role involves installation, jointing and termination of HV and LV power cables, delivered within some of the UK’s most space-constrained and operationally sensitive environments.
From deep-level substations and ventilation shafts to surface switch rooms and critical traction feeder locations, ADY-HV provides technically assured jointing solutions that meet the unique demands of London’s underground rail network.

Scope of Works

  • High- and low-voltage cable jointing up to 33kV across underground and surface substation locations.
  • Terminations into legacy and modern switchgear, transformers and distribution panels.
  • Support for substation upgrades, including cable glanding, sealing and earthing.
  • Work in confined and restricted-access spaces, including deep tube and escalator-adjacent chambers.
  • Phasing, testing assistance and interface with commissioning teams for energisation readiness.
  • Asset documentation and red-line drawing support for TfL’s project handover requirements.
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Talk to Us

  • ADY-HV has the technical expertise, certifications, and delivery model required to support complex HV installations across the London Underground network. From deep tube substations to critical feeder renewals, we’re ready to help you deliver safe, efficient and standards-compliant power upgrades.
  • Get in touch: Let us support your London Underground projects with proven HV solutions that deliver — even underground.
Contact Us

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