Energy saving potential of different setpoint control algorithms in mixed-mode buildings

Mixed-mode buildings can combine the use of natural and mechanical systems to achieve the desirable internal conditions. However, it is essential to effectively control a mixed-mode building to minimize the energy consumption without compromising the thermal comfort of the occupants. The aim of this research is to develop different setpoint control algorithms for mixed-mode buildings, by using a variety of adaptive methodologies such as ASHRAE Standard 55, IMAC model and EN15251, and evaluate their energy saving potential for Bangalore and Mumbai, India and Gatwick, UK. Cosimulations were used for this research. EnergyPlus was used to develop the building geometry and coupled with Modelica, where the control algorithms were developed. This is a novel simulation approach to assess control algorithms in buildings and provides great flexibility for future use of the control algorithms. The results showed that the effective control of mixed-mode building can result approximately in 40% energy saving in Indian cities compared to fully mechanical conditioned buildings whilst maintaining comfortable internal conditions for 90% of the year.