By their very nature ‘fugitive’ emissions can, at best, only be estimated during the design stage of an embodied carbon report, often called a Life Cycle Assessment (LCA). A LCA is a method of evaluating the environmental burden of processes and products during their life cycle from cradle to grave. Post installation record keeping of fugitive emissions can inform subsequent reviews, and reporting. Giving exaggerated importance to estimated fugitive emissions may compromise the selection of air conditioning equipment that is demonstrably more suitable for the application, and in many cases more energy efficient than the alternatives.
Fugitive emissions refer to the gases or vapours that are released from pressurised equipment due to leaks, evaporation, or other unintended or irregular releases. In the context of refrigerant gas within air conditioning systems, fugitive emissions refer to the leakage of refrigerant gases into the atmosphere.
Refrigerant gases are commonly used in air conditioning/heat pump systems as part of the mechanical cooling/heating cycle. Refrigerant gases may escape from the system due to various reasons such as equipment failure, poor installation, neglect during maintenance, and as part of final decommissioning.
Fugitive emissions are rightly a concern, many refrigerants are potent greenhouse gases. For example, commonly used refrigerants like hydrofluorocarbons (HFCs) have a much higher global warming potential than carbon dioxide. Even small amounts can contribute significantly to global warming.
It is not only good practice to mitigate against fugitive emissions refrigerant handling is also covered by several UK regulations and standards:
The legislation above illustrates that prevention of fugitive emissions is something that the industry is focused on and that the loss of refrigerant, other than through exceptional circumstances, is entirely preventable.
Failure to comply with the applicable regulations can result in significant fines for responsible parties (beyond engineers and contractors). Therefore, it's crucial for landlords and building managers to ensure that the handling of refrigerants is done responsibly and in accordance with the law.
The importance of Technical Asset Management in this regard should not be underestimated, site auditing is key to responsible building management, read more here.
LCAs assess the environmental performance of a building and the outputs have numerous environmental indicators but are often collectively referred to as the amount of Carbon Dioxide equivalent (CO2e) emitted during the manufacture, transport, and construction of building materials, together with end-of-life emissions. BS EN 15978-1 provides a calculation methodology for the assessment of environmental performance of buildings.
Whilst it is normal practice to include fugitive emissions within LCA reporting, it is also good practice that the reader is given guidance on their relevance, and importance, in understanding the buildings overall total environmental impact.
Diligence should be taken to source manufacturers data, as an example, Daikin¹ recommend the following percentages for embedded carbon reporting:
This information confirms that:
In conclusion the reporting of fugitive emissions should be done with care, and reports should include explanatory notes. There are many factors when considering equipment selection, whilst embodied carbon is one of them it should form part of a holistic approach.
A whole life carbon assessment (WLCA) standard can estimate the amount of carbon emitted throughout the life cycle of a constructed asset, from the early stages of development though to the end of life. It gives visibility to embodied carbon, operational carbon, and user carbon.
¹ Daikin Pol01 BREEAM Calculation Default Values
Resero undertake Life Cycle Assessments and whole life carbon assessments as part of our
Technical Asset Management consultancy.