Aug 9, 2022
4 Key Areas the Construction Industry Needs to Focus on to Achieve Net-Zero
Exploring whole life carbon relating to HVAC systems, offering solutions and advice to promote the move towards a net-zero future.
Recently, the focus has shifted heavily toward the aim to reduce the environmental impact of the built environment to address the climate crisis. Emissions from greenhouse gasses, measured in carbon dioxide-equivalent emissions, are responsible for global warming, and they need to be reduced drastically and quickly.
For a long time, the industry has focused on operational carbon, while somewhat overlooking the rest of the life cycles relating to the carbon emissions of a building.
HVAC systems are responsible for ~40% of the built environment emissions, with approximately 50% of this coming from them before they’ve even been turned on (embodied carbon).
1. The Importance of Data
If we are to truly track the impact of carbon emissions, and the level of reduction that new technology is generating, there must be a much larger commitment to tracking data through testing, research and real-life scenarios.
Manufacturers across the industry must work to collect and publish data on embodied carbon.
For HVAC products that can prove to be quite difficult due to their complex supply chains, but it is essential if we are to meet whole life net zero carbon targets.
2. Energy Efficiency
To truly reduce the amount of whole life carbon with HVAC systems, the efficiency of the systems must be made a priority.
At product level, selecting new, low-GWP refrigerants that are much kinder to the environment is paramount. However, this doesn’t just benefit the reduction of carbon, it can also benefit the performance of the HVAC system itself, as many low-GWP refrigerants have more efficient thermal performance properties which can lead to improved product efficiencies.
At building level, utilising systems that are more energy efficient, will help to drive down energy usage. As we move towards electrification of buildings, energy efficient systems and products will drive down energy demand from the grid which in turn will reduce our total energy usage. Smart building controls can create smart buildings, which can measure and learn about the building occupant usage, and then intuitively adapt the outputs to ensure maximum efficiency (lowest running costs, lowest operational emissions). Smart Buildings can be connected to Smart Grids/ Smart Networks, and then we can realise huge benefits from load management and load balancing, reduce demand over peak times and better reduce waste demand energy and improve the efficiency of whole network usage.
3. Servicing and Maintenance
The average lifetime of a HVAC system is around 15 years, while the lifetime of a building is around 60 years. In order to protect the long-term carbon emission rate of both the building and the HVAC solution within it, correct maintenance of products is essential.
Regular servicing of HVAC systems ensures that the systems perform to an optimal level over the course of its lifetime.
It’s also worth noting that many HVAC systems, have leakage rates associated to the refrigerants within them. CIBSE and many other industry bodies work on research to produce data that clearly defines expected leakage rates over the lifetime of a product, several manufacturers have contradictory data — but the point remains the same; we (the whole supply chain) must do all that we can to minimise any and all leakage where possible. That involves rigorous strength testing of equipment by manufacturers, stringent requirements and guidance on installation and best practices, comprehensive skills training from the sub-contractors and installers, regular service and check-up packages, and comprehensive controls/ BMS monitoring of systems, to name just a few key elements that all need to happen to reduce leakage, reduce environmental impact, and improve safety.
Additionally, the indoor air quality may also be affected by an unmaintained system (such as dirty filters on any internal units), which generates even more problems outside the carbon issues.
4. Retrofits and the Circular Economy
Considerations must be given towards how HVAC systems are dealt with at the end of their lifetime.
The increase in recyclability of products must be a priority so that systems can be broken down and reutilised into future products, and in some cases, solutions can be revamped and retrofit with the replacement of certain aspects within uphauling the system in its entirety.
We need holistic thinking across the industry, to move away from a linear supply chain (cradle to grave) towards a circular supply chain/ economy (cradle to cradle). In-use, repair, replacement and refurbishment, are as vital to the success of WLC approach as the end of life stages for decommissioning and deconstruction as opposed to the current demolish and start again processes.
The main priority for real estate owners and developers in the short and long term is to produce carbon-neutral buildings. By taking a whole life approach to reducing carbon emissions relating to HVAC systems, solutions can be truly futureproofed for the coming decades.
