Simulating the Impact of HVAC Control Strategies on Supermarket Energy Use
Henry Witt, Loughborough University
Background:
The heating, ventilation and air conditioning (HVAC) system in a typical supermarket is responsible for between 15% and 25% of the total energy use, accounting for a significant proportion of the CO2 emissions. Energy use reductions can be achieved using energy efficient HVAC system design, operation and control. HVAC system control strategies adopted in non-domestic buildings are typically basic ones. More sophisticated approaches to HVAC system control involve Energy Management and Control System (EMCS) strategies and humidity control. EMCS strategies have been shown to be a cost effective means of decreasing energy use in many types of non-domestic building. However, their impact in supermarkets is difficult to predict and has not been quantified in the UK. One reason for this difficulty is the complex interaction between the HVAC and refrigeration systems in supermarkets.
Method:
Simulations in EnergyPlus will be used to assess the potential of EMCS strategies and humidity control for reducing supermarket energy use. A demonstration model of a generic supermarket building was developed to explore the interaction between the HVAC and refrigeration systems as well as the method of adding EMCS strategies and humidity control. Thensuperstore building models, representing a supermarket building category, will be developed and validated using sub-metered energy data and measurements of internal temperature and relative humidity (RH). Several EMCS strategies and humidity control will then be implemented within the EnergyPlus model. Initially these will be applied individually, but where appropriate the strategies are to be combined to assess their joint impact on energy use.
Research Questions:
- What is the impact on UK supermarket energy use of employing EMCS strategies and humidity control?
- To what extent do EMCS strategies and humidity control influence the interaction between refrigeration and HVAC systems in supermarkets?
- Can the implementation of EMCS strategies and humidity control in UK supermarkets be cost-effective?
Aim:
Investigate the impact of Energy Management Control System (EMCS) strategies and humidity control on the total energy use of UK supermarkets.