Run a heat network or steam supply business

Supplying heat, steam or cooled air — a district heating network, a campus steam main, a communal cooling system — has historically sat outside utility regulation. That is changing: the Energy Act 2023 brings heat networks under Ofgem. Alongside the new regime, the plant itself carries established duties — pressure systems, F-gases, building standards and energy audits. This guide covers the operator duties; if you install or service this plant for others, see specialist approvals for repair and installation work.

Get authorised as a heat network operator

The Energy Act 2023 creates mandatory Ofgem authorisation for heat network operators, with consumer-protection obligations and technical and financial fitness criteria, phased in from 2024. If you run district heating or cooling, track the implementation timetable and prepare for authorisation — and comply with the Heat Network (Metering and Billing) Regulations now.

Maintain your pressure systems lawfully

Steam generation and distribution plant — boilers, pressure vessels, high-pressure steam mains — needs a written scheme of examination drawn up by a competent person, with periodic examinations and records. This applies in Great Britain.

Hold F-gas certification for cooling plant

If your air-conditioning or cooling plant contains fluorinated greenhouse gases, your company needs an F-gas company certificate and your engineers personal certificates, with leak-checking and record-keeping scaled to the system's charge. This is the GB regime, administered by the Environment Agency.

If you also service or maintain customers' refrigeration and air-conditioning equipment, see F-gas and WEEE duties for repair businesses.

Meet building energy standards for installed plant

Heat and steam plant installed in or connected to buildings in England must meet Part L of the Building Regulations 2010 (conservation of fuel and power), with building-control notification for notifiable works. Wales has its own Part L, Scotland uses Section 6 of its building standards, and Northern Ireland Part F.

Certify Good Quality CHP under CHPQA

If you operate combined heat and power plant, registering with the CHPQA programme and meeting the Quality Index threshold earns Good Quality CHP status — the gateway to Climate Change Levy exemption and business-rates relief on generating plant and machinery. The programme is UK-wide.

Run ESOS energy audits if you are large

Large undertakings — 250 or more employees, or annual turnover above £44 million with an annual balance sheet total above £38 million — must complete an ESOS energy audit every four years and notify the Environment Agency. The Phase 4 deadline is 5 December 2027.

Next steps

Put the duties every energy business shares in place with run a compliant energy business, and confirm your position with the energy compliance checklist.