In a recent live webinar titled "Reducing Embodied Carbon in MEP - Why it matters & what you can do about It," Dr Anastasia Mylona, CIBSE's Technical Director and Panu Pasanen, CEO of LCA One Click, investigated the elevated MEP embodied carbon, its implications compared to operational carbon and practical strategies for its mitigation.
Embodied carbon refers to all carbon emissions associated with a building's lifecycle until it begins operational use. This encompasses emissions from materials, manufacturing, transportation, construction, maintenance, eventual demolition and transportation to waste recycling. Notably, it includes all installed building components, construction wastage, and eventual replacements of MEP equipment. Additionally, refrigerant leakages during operation contribute to embodied carbon.
According to GLA’s Whole Life Cycle carbon assessment guidance, the embodied carbon of building services in new buildings is on average 25% and in retrofits it could be up to 75%. The significant contribution of MEP carbon emissions to embodied carbon in buildings is influenced by several factors. Firstly, the frequency of equipment replacements plays a vital role, as more frequent replacements result in greater carbon emissions. This includes disposal of old equipment and manufacturing, transportation and installation of new components.
Secondly, refrigerants used in MEP systems significantly contribute to embodied carbon, necessitating careful selection of environmentally friendly options. Lastly, energy consumption, either from the grid or additional MEP systems for energy generation, impacts operational carbon. Oversizing MEP systems due to risk aversion and reluctance to discuss risks with clients further exacerbate emissions.
In essence, cooling, heating and energy generation are the primary drivers of MEP carbon emissions, highlighting the importance of thoughtful system design and consideration of future scenarios to achieve sustainability goals. The embodied carbon is the next frontier after operational carbon towards decarbonisation of the build environment. The shift towards embodied carbon represents a significant evolution in sustainability efforts within the building industry. Historically, the focus has been on reducing operational carbon through energy efficiency measures. However, as energy consumption decreases and buildings become more efficient, the proportion of embodied carbon relative to operational carbon increases.
This shift underscores the critical importance of addressing embodied carbon emissions from building materials and MEP equipment. Modern buildings, reliant on MEP systems and energy production technologies, substantially contribute to embodied carbon. Viewing embodied carbon as the "next frontier" suggests it has become a key commercial and competitive consideration, offering opportunities for differentiation and market advantage.
As awareness grows and stakeholders seek solutions to reduce embodied carbon, it transitions from an academic topic to a commercially viable concept increasingly understood by industry professionals and clients. Challenges remain in upskilling the industry and aligning stakeholders towards common sustainability goals.
Prioritising passive solutions like optimising building orientation and natural ventilation, alongside effective shading strategies, is crucial. Addressing the refrigerant issue by choosing low-carbon or natural refrigerants and minimising leakage is essential. Avoiding over-engineering and accurately sizing MEP systems based on building and occupant needs minimises waste and energy consumption. Designers should consider lifecycle impacts when specifying products, focusing on factors beyond price alone. Integrating these strategies empowers MEP designers to advance sustainability goals and reduce environmental impact.
Watch the full webinar below: