The Department for Energy Security and Net Zero has released the draft Heat Network Technical Standard (TS1), a landmark development in the transition to a regulated heat network market in Great Britain.
TS1 will supersede the widely adopted CP1 (2020) Code of Practice, creating a shift from a voluntary code of practice to a formal standard that will underpin the forthcoming Heat Network Technical Assurance Scheme (HNTAS).
TS1 has been developed with the overarching intention of ensuring that heat networks are designed, built and operated to acceptable minimum standards throughout their life-cycle.
There are four key aims of TS1, which are met through achieving a set of objectives at each stage of the standard.
The key aims are to:
- Meet consumers’ heat demands reliably
- Minimise the cost of heat over the lifespan of the heat network
- Ensure sufficient operation and reliability during the design, construction and operation of the heat network
- Reduce carbon emissions associated with the provision of heat.
The technical authors of the document, FairHeat, engaged extensively with industry experts in a 14-member technical standards committee, as well as with four specialist technical sub-working groups to shape a standard grounded in technical rigour, industry consensus and real-world deliverability.
A number of key changes have taken place from CP1 (2020) to TS1, including: new heat network requirements; rewriting of minimum requirements; a new structure; and new requirements to address gaps and/or shifts in industry thinking.
New heat network requirements
Minimum requirements have been introduced in key technical areas, with engagement from specialist technical sub-working groups made up of industry experts in each key technical area.
These new minimum requirements cover the following technical areas: pressure, resilience, water quality, insulation, and condition of pipework and equipment (see panel, ‘New heat network requirements’).
Rewriting of minimum requirements
Minimum requirements for heat networks that have been retained from CP1 have been rewritten to ensure that they are suitable for TS1 as a regulatory technical standard. This includes:
- Resolving ambiguity to ensure that requirements are suitable for assessment
- Ensuring that language is in line with ISO guidelines
- Aligning terminology with HNTAS
- Splitting requirements where there are different requirements for different elements of a heat network.
Structure
TS1 has been structured across seven stages, which align with the Technical Standards and Assessment Procedures set out in the forthcoming HNTAS documents to establish a consistent foundation for the introduction of the regulatory regime for heat networks in Great Britain.
New requirements to address gaps and/or shifts in industry thinking
While TS1 is largely based on CP1 (2020), there are a select number of areas in which there are clear gaps, or shifts in industry thinking. Notable examples include:
- Updates to the calculation methodologies used as part of pipe-sizing assessments to ensure sufficient performance of heat networks and that consumer needs can be met
- The development of a new key performance indicator for heat losses as a measure of efficiency of district heat networks.
The draft publication gives the sector early visibility of the regulatory baseline that will underpin heat networks from 2026 onwards. Once finalised, TS1 will form the backbone of the technical requirements set out under HNTAS, enabling Ofgem-regulated oversight and greater protection for consumers.
New heat network requirements
Pressure
Working pressures in heat networks require detailed assessment during their design and can present operational risks if overlooked or poorly understood. The new minimum requirements aim to ensure that risks posed by working pressures in heat networks are sufficiently identified, assessed and mitigated where appropriate.
Resilience
Here, new minimum requirements have been created to ensure that heat networks minimise interruptions to the supply of heat by preparing and planning to absorb, recover from, or more successfully adapt to adverse events or threats. This includes ensuring that resilience is factored into the design of heat networks and proactively managed during operation.
Water quality
There is already guidance covering water quality in heat networks, with a particular focus around installation activities. Literature has also been spread across a range of documents, which varies depending on the type of water quality systems followed.
The new water quality minimum requirements have been developed to cover water quality across all stages of a heat network’s development, to ensure that it is appropriately managed throughout the planning, design, construction and operation of the heat network. This includes establishing water quality key performance indicator thresholds and recording requirements.
Insulation
HNTAS will set out heat-loss requirements (as a measure of efficiency) that heat networks must meet during their design and operation. Minimum requirements have been developed within TS1 to aid designers in achieving these heat loss limits while being technically feasible.
Condition of pipework and equipment
Components of heat networks, such as pipework and equipment, inherently have an operational lifespan, which can lead to operational problems if not understood or managed properly. The minimum requirements regarding condition aim to reduce the risk of deterioration and failure of components in heat networks through a framework of early identification and remediation.
Access the draft version of TS1 here
https://bit.ly/CJTS1dr
[ABOUT THE AUTHOR]
Charlie Davies is a consulting engineer at FairHeat