Combining our expertise in low-energy projects and our experience in the commercial office sector, our engineers created a future-ready design that took advantage of the UK’s temperate climate. The mixed-mode all-air heating, ventilation and air-conditioning (HVAC) system will reduce our operational energy use by around 65%.
Designing a responsive and efficient system
Free cooling comes from connections to the façade on each floor. When conditions are right, the system can bring air directly in from outside and use it for cooling without the need for chillers. At other times, heat from the building can be recovered and reused at the air handling units, with reversible heat pumps at roof level providing low-carbon heating.
We also introduced louvres on office floors to supplement the building’s air supply. They are connected to a smart building management system (BMS) that manages fresh air flow around the office based on occupancy and CO2 levels. Because it’s linked to the integrated booking system, the BMS knows when each meeting room is booked and can bring the temperature and air circulation up to the optimum levels in time. Should people not arrive for their booking, the system is able to detect that the room is empty and can shut off the heating and circulation to that room to save energy.
To reduce energy use further, we are developing a split HVAC system. We designed two plant rooms: one for the east side of the building and one for the west side. So if occupancy is low we can direct people to use only one half of the building and shut the other side down to save energy. This will be implemented post-occupancy, combined with staff engagement that encourages people to adopt behaviours that reduce energy use.