
Substation Design and Construction (GRP and Traditional)
We provide turnkey substation design and construction services, including both GRP packaged substations and traditional brick-built substations.
Our scope typically covers:
Civil design and construction
Transformer bunding and plinth installation
HV and LV switchgear installation
Protection and control panel integration
Earthing systems and earth grid installation
Testing, commissioning and energisation


HV Cable Installation and Jointing
Hardtech HV delivers professional high voltage cable installation and jointing services across a wide range of environments. High voltage cable systems are critical infrastructure. Installation quality matters.
Our expertise includes:
11kV and 33kV HV cable installation
Ducted and direct-buried systems
Cable terminations and indoor/outdoor sealing ends
Straight joints and transition joints
Pressure testing and VLF testing


Private Network Infrastructure (LV-33kV Networks)
Hardtech HV designs and delivers private electrical networks from LV up to 33kV, supporting complex industrial sites, commercial facilities, renewable energy developments and multi-building estates.
Our private network solutions include:
11kV and 33kV HV distribution systems
Ring main units (RMUs) and switchgear installation
Transformer installations and LV distribution boards
Embedded generation integration
Metering and control systems

Network Upgrades, Diversions and Reinforcement
Hardtech HV delivers network upgrades, diversions and reinforcement works to support development, capacity increases and infrastructure modernisation.
We provide:
Capacity upgrades and transformer replacements
HV cable diversions
Network reinforcement schemes
Integration of renewable generation
Phased upgrades to live environments


What experience does Hardtech HV have with substations?
We provide turnkey substation construction, including GRP packaged and traditional brick-built substations. Our scope covers foundations, transformer plinths and bunds, HV/LV switchgear, protection and control panels, earthing systems, and full testing and commissioning. Substations are delivered to DNO or private network standards, with accessibility, safety, and longevity in mind.

Does Hardtech HV install and joint HV cables?
Yes. We install and joint 11kV and 33kV HV cables, including ducted or direct-buried systems, indoor/outdoor terminations, and straight or transition joints. All works are completed by qualified jointers, with full testing, commissioning, and documentation to ensure reliability and compliance.

What protection, control, and earthing systems does Hardtech HV design and install?
We design and install protection relays, grading schemes, interlocking systems, control panels, HV and LV fault protection, and earthing grids. All systems are tested for correct operation under fault conditions, ensuring personnel safety, network reliability, and compliance with relevant standards.

Can Hardtech HV upgrade, divert, or reinforce networks?
Yes. We deliver upgrades, diversions, and reinforcement of LV and HV networks, including transformer replacements, cable diversions, network strengthening, renewable integration, and phased works in live environments. We plan works carefully to minimise disruption while ensuring compliance with industry standards.

How does Hardtech HV maintain safety during construction projects?
All construction work follows strict risk assessments, method statements, and safe systems of work. Our team ensures both personnel and equipment are fully protected during substation and network installations.

What types of clients does Hardtech HV build networks for?
We work with developers, principal contractors, industrial facilities, and commercial operations to deliver high-quality HV and LV infrastructure tailored to each project.

How long do construction projects typically take?
Timelines depend on project complexity, site conditions, and required approvals. Our structured approach ensures feasibility, design, installation, and commissioning phases are completed efficiently.

What makes Hardtech HV different in construction work?
We combine technical expertise, practical experience, and NERS-accredited ICP capability to deliver safe, compliant, and long-lasting network installations.

Get in touch to discuss your project, challenges, or requirements. Our specialists are ready to support you end-to-end.