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CrestWatt

UK electrical engineering contractor

Electrical contracting for utility-scale solar, storage and grid connections.

Contestable connections, HV substation packages, protection and control, cable termination from DC to 132 kV, and the testing and commissioning programme that carries a project from installation complete to energised and accepted.

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33 kV switchgear room on a UK solar project during commissioning.
Fig. 1 — Single line, point of connection to string Scope under one contract
  1. ≈ DNO network 132 / 33 kV
  2. PoC Point of connection Contestable works
  3. SG HV switchgear 33 / 66 kV
  4. Tx Transformer station 33 kV / LV
  5. ~/= Inverter AC / DC
  6. CB Combiner box DC · Modbus
  7. PV Strings MC4 · 1500 V DC

DNO RETAINED

CRESTWATT SCOPE — CONNECT · TERMINATE AND TEST · COMMISSION · OPERATE

  • LV, MV and HV cable termination and testing to 132 kV
  • DC, MC4, fibre and Modbus termination
  • IEC 62446-1 PV commissioning
  • Protection secondary injection and IEC 61850
  • 33 kV and 66 kV switchgear and protection supply
  • Electrical site supervision
  • O&M

72 MW

Solar PV: data and communications commissioning across 13 transformer stations and 213 string combiner boxes.

66/33 kV

Grid substation: switchgear, protection relays, CTs, VTs and cable accessories supplied and integrated on a 40 MW solar farm.

480 MW

Three-phase solar development: PV and electrical design as framework subcontractor to a European EPC.

Scope of work

All eight services →

01

Connect

Contestable connection works from application to adoption: HV cable, point of connection substations, metering, protection and earthing to DNO specification and ENA Engineering Recommendations.

02

Terminate and test

Cable termination and testing from DC string level to 132 kV. Heat shrink, cold shrink and separable connector terminations; MC4 assembly; fibre fusion splicing; Modbus RS-485 termination. IR, VLF, sheath, TDR, OTDR, secondary injection.

03

Commission

Structured commissioning to IEC 62446-1 on the DC side and to DNO and owner’s engineer requirements on the AC and HV side, with every result recorded digitally against the test plan and compiled for FAC.

04

Operate and maintain

Planned preventive maintenance, protection re-verification, thermographic survey, HV cable fault location and repair, and authorised person cover for operational plants.

Why CrestWatt

One contractor from the point of connection to the string.

Utility-scale solar and storage projects typically split the electrical scope across four or five contractors: the ICP, the substation installer, the DC installer, the communications subcontractor and a commissioning agency. Each interface is a programme risk. CrestWatt delivers the full electrical scope under a single contract, with one test plan, one records system and one team accountable for energisation.

CONVENTIONAL — 5 CONTRACTS, 4 INTERFACES

ICP
SUBSTN
DC
COMMS
T&C

CRESTWATT — 1 CONTRACT, 1 TEST PLAN

POINT OF CONNECTION → STRING

  • Defined completion.

    Scopes end at witnessed energisation and signed acceptance, with the handover pack delivered, not at mechanical completion.

  • Supply and integration under one contract.

    Switchgear, protection relays, CTs, VTs, cable accessories and control panels sourced through authorised distribution or vetted manufacturers, factory tested, installed and commissioned by the same engineers.

  • Named methods and standards.

    Every test on our schedule cites its method and acceptance criterion. Clients and DNOs know what they are witnessing before they arrive.

  • Digital records from day one.

    Inspections, tests and witness points are captured on site, on the day, in a structured format. The FAC pack is compiled as the work proceeds.

Sectors

Detail →
  • Utility-scale solar PV 10 MW – 500 MW
  • Battery energy storage 10 MW – 100 MW and above
  • Grid connections and substations 11 kV – 132 kV
  • Industrial and commercial HV Private networks

Recent work

All projects →

  • 72 MW solar PV, England

    Data cable testing and termination, SCADA and monitoring commissioning across 13 transformer stations.

  • 40 MW solar farm with 66/33 kV grid substation, West Yorkshire

    Electrical site supervision; 33 kV switchgear and protection supply; 66 kV cable sealing ends; fibre and CAT7 certification.

  • 480 MW solar development, three phases

    PV and electrical design under a framework agreement with a European EPC.

Send us the single line diagram and the programme.

An engineer will confirm within two working days what scope we can take on and the earliest mobilisation date.

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