EMBODIED CARBON | TM65 GUIDANCE HEART OF THE MATTER Embodied carbon in MEP equipment makes up a large proportion of building emissions, but is hard to measure. Elementa Consultings Louise Hamot and Clara Bagenal George explain how CIBSEs TM65 methodology estimates components environmental impact Guidance for engineers and consultants on actions to reduce the embodied carbon emissions of MEP equipment Guidance on EPDs, and how to use and create them Where no EPDs are available: guidance on how to calculate embodied carbon of MEP products a consistent approach for collecting the data required for the calculations a consistent approach to the way embodied carbon calculations for MEP products are undertaken and reported (at product level). MEP basic embodied carbonreduction strategies CIBSEs TM65 provides step-by-step guidance on calculation methods B uilding services engineers have been at the forefront of efforts to reduce operational carbon emissions in buildings through improvements to the design, specification and optimisation of mechanical, electrical and public health (MEP) systems, and the performance of building skins. But MEP equipment also has significant embodied carbon the emissions associated with extraction of materials, production and transport of products, and their repair, replacement, disassembly and disposal. To drive down the whole-life environmental impact of the systems they design and the products they specify, engineers must improve their awareness of emissions as a result of embodied carbon. MEP components are often mainly made of metals, which have high embodied carbon. Their supply chain is complex, and can involve many manufacturing processes and long transport distances. Large quantities are installed within buildings and replaced regularly. Environmental product declarations (EPDs) are a standardised way of expressing embodied carbon and other environmental impacts throughout the life-cycle of a product. Very few manufacturers of MEP products offer EPDs, however, mainly because of the complexity of MEP products and their supply chains, but also because incentives from the market and regulators are absent. As a result, the building services industry has had little access to vital data about the embodied carbon of MEP products. Aims of TM65 This document sets out to provide: An introduction to whole-life carbon and embodied carbon within building services Embodied carbon emissions associated with building services design can be reduced without the need for complex calculations by implementing simple design strategies. The most effective way to reduce the embodied carbon of MEP systems is to design out, or at least reduce, the use and overall weight of the equipment. Once this has been done, the embodied carbon of MEP plant can be further reduced by specifying equipment with: Low refrigerant GWP and leakage rates Long lifetimes Materials with low embodied carbon Products and components that can be demounted and reused Products that can be disassembled, and whose materials can be recycled. It should also be easily accessible for inspection, maintenance and replacement. Embodied carbon calculation guidance when no EPD is available There is a lack of easily accessible embodied carbon emissions data associated with MEP products, so CIBSE has created calculation methods to estimate embodied carbon at the product level based on specific information from manufacturers. Two calculation methods are provided depending on the amount of information collected through a manufacturer form. Users of TM65 are encouraged to share the results of their calculations with CIBSE through a reporting form at the end of the process. 26 January 2021 www.cibsejournal.com CIBSE Jan21 pp26-27 Embodied energy.indd 26 18/12/2020 17:05