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• Implementation of a model predictive control scheme for HVAC systems is presented. • The hardware/software solution is generalisable to most building management systems. • Cloud solutions can offer low-cost, scalable control in commercial buildings. • Economic MPC reduced energy usage by 1.7% compared to baseline control. • Building thermal performance strongly affects viability of MPC schemes. Many businesses are looking for ways to improve the energy and carbon usage of their buildings, particularly through enhanced data collection and control schemes. In this context, this paper presents a case study of a food-retail building in the UK, detailing the design, installation and cost of a generalisable model predictive control (MPC) framework for its Heating, Ventilation and Air Conditioning (HVAC) system. The hardware/software solution to collect relevant data, as well as the formulation of the MPC scheme, is presented. By utilising cloud-based microservices, this approach can be applied to all modern building management systems with little upfront capital, and an ongoing monthly cost as low as $6.39/month. The MPC scheme calculates the optimal temperature setpoint required for each Air-Handling Unit (AHU) to minimise its overall cost or carbon usage, while ensuring thermal comfort of occupants. Its performance is then compared to the existing legacy controller using a simulation of the building's thermal behaviour. When simulated across two months the MPC approach performed better and achieved the same thermal comfort for a lower overall cost. The economic optimisation resulted in an energy saving of 650 kWh, with an associated cost savings of $240 (an improvement of 1.7% compared to the baseline), while the carbon optimisation gave negligible CO 2 savings due to the inability of the building to shift heating to low-carbon periods. Findings from this study indicate the potential for improving building performance via MPC strategies, however the level of impact will depend on specific building attributes. [ABSTRACT FROM AUTHOR]

Abstract: Following the Japanese Cool Biz campaign which advocated relaxed dress codes and cooling set-points of 28°C in air-conditioned public buildings, other countries have introduced similar policies, with temperature limits varying in different countries. In the UK the British Council for Offices suggested that the summer cooling set-points of UK air-conditioned offices should be increased by 2°C from the previously recommended 22±2°C. However, these recommendations are largely supported by desk-based analysis rather than using field studies. This paper presents the findings of a blind, controlled intervention study conducted in the summer of 2010 in an office building in London to investigate the effects of increasing the current cooling set-point to 24°C. The temperature of one floor was changed and compared with a ‘control’ floor where the set-point remained unchanged. The indoor air temperatures were measured at various locations across the floors to monitor the temperatures the occupants were experiencing. The BUS post-occupancy evaluation survey was used to assess occupants’ self-reported comfort and satisfaction, whilst the NEP questionnaire was used to estimate occupants’ environmental attitudes. The findings from statistical analyses of the data collected for all 129 participants suggest that increasing the set-point temperature led to the occupants feeling significantly warmer in comparison with the group at lower temperature settings. Nevertheless, this did not affect the self-reported thermal comfort of the occupants in the intervention group, as depicted by an insignificant difference between the two groups. It was also observed that there is a positive correlation between the occupants’ tolerance of higher indoor air temperatures and their environmental attitudes, indicating that this could play a key role in the acceptance of indoor temperature changes in the UK. [Copyright &y& Elsevier]