The ‘Research Acceleration and Demonstration’ (RAD) Building at the University of Nottingham is an ambitious project which provides laboratories, offices and break-out spaces for various groups, as part of the Energy Research Accelerator (ERA) initiative. The 2,500m², £5.4m facility targets both BREEAM Excellent and Passivhaus certification, and if successfully certified, will become the largest working Passivhaus laboratory in the UK.
Greenlite Energy Assessors worked extensively with building services engineers MIES and Passivhaus consultants Etude to assess the overheating risk of the building under the CIBSE TM52 thermal comfort metric. We later developed these works further to aid Passivhaus certification, by way of calibrating the fan energy used to ventilate and cool the building.
More than ever, it was essential with this particular project that the thermal modelling accurately matched reality, hence a great deal of emphasis was placed on fully understanding how HVAC system controls operate and the demonstration that these were mirrored in the modelling. This can be observed in our report.
The exercise essentially helped tread the fine line between ensuring that HVAC and other parameters were sufficient to ensure CIBSE TM52 thermal comfort compliance, whilst at the same time, ensuring that fan loads were minimised in order to aid Passivhaus certification. We did this by undertaking a large number of simulation variants, establishing the impact of different daytime and night-time ventilation set-points and controls until we honed in on the an optimised solution.
Because the building design was not initially designed with Passivhaus in mind, this tightened the tolerances between achieving both thermal comfort and Passsivhaus compliant energy efficiency, making the exercise all the more relevant.
Will South of Passivhaus Consultants Etude comments:
“Greenlite worked hard to provide the input to demonstrate that the RAD building meets the Passivhaus summer comfort criteria. It was a challenge to balance the heating energy targets, ventilation rates and summer comfort criteria for a building where the design was already fixed, and Richard worked hard to find sensible solutions that were acceptable to the client.”