Earlier this year, the Sustainable Energy Authority of Ireland (SEAI) completed a major study looking at how Ireland can meet its target to achieve net zero carbon emissions by 2050 by decarbonising heating(1). One of the key areas of focus were heat network schemes.
At present, these networks contribute less than 1% of the heat used in Ireland; however, the SEAI expects that by 2050, more than 50% of heating demand will be met through these sources. Given this rapid expansion, it is important for contractors to get up to speed with best practice.
CIBSE CP1 Heat Networks: Code of Practice 2020 (CIBSE CP1 2020) can provide a useful starting point for all project teams. The document covers all stages in the development, installation and operation of a network, setting clear checklists, including 540 minimum requirements, and highlighting how additional improvements to areas such as pipe insulation can help raise system performance.
Kingspan Kooltherm Pipe Insulation is one of the most thermally efficient products commonly available for the insulation of pipework – providing an effective barrier against heat loss.
Why heat networks
Heat networks distribute heat from an energy centre to either an individual building (communal heating) or multiple buildings (district heating). One of the key advantages with this technology is that it is ‘fuel agnostic’, meaning a whole range of sources can be used for the energy centre. It is therefore possible to install a network which initially uses a gas-powered energy centre, then transition to a low-carbon alternative as they become available.
CIBSE CP1 2020 is designed to assist the effective deployment of networks at all scales. The insulation of secondary pipework (the pipework that runs inside the building) provides a good example of how it works – setting out simple minimum requirements whilst encouraging specifiers to look to enhanced specifications.
Available for both standard and non-standard pipe diameters, the product provides an energy saving and thermally efficient solution for secondary pipework.
Objective 3.9.7 of CP1 provides minimum insulation thicknesses for different secondary pipe diameters. In most cases, a 50 mm thickness of either phenolic or mineral fibre pipe insulation is required.
It’s important to be aware, however, that phenolic insulation is notably more effective at preventing heat loss at a given thickness than mineral fibre insulation. As such, heat losses may increase by between 30% and 39% when the minimum mineral fibre specification is used instead of the phenolic equivalent.
To address this, CP1 requires project teams to carry out pipework heat loss calculations at the Feasibility Stage (Stage 2) and to create detailed pipework insulation specifications based on project specific parameters at the Design Stage (Stage 3). Objective 3.9.8 of CP1 lays out the calculation methodology that should be followed, with maximum permissible heat losses and best practice targets.
The exact thickness requirements will vary between projects, however the use of a more thermally efficient pipe insulation, such as phenolic, means it should be possible to meet these requirements with a notable thinner thickness than would be possible with mineral fibre.
CP1 also highlights the importance of ensuring a continuous layer of insulation across all areas of the services and the use of “rigid low conductivity inserts” to prevent heat transfer through pipe support.
Ticking all the boxes
Heat networks are set to play a major part in Ireland’s shift to a net zero carbon built environment. The minimum requirements and checklists within CIBSE CP1 can provide a useful starting point when tackling these projects, ensuring aspects such as pipework are properly insulated.
For more information: Kingspan Insulation Ltd, Castleblayney, Co Monaghan. T: +353 (0) 42 975 4219