Symbolic modelling and predictive assessment of air source heat pumps

This article extends a novel advanced dynamic calculation method (IDEAS - Inverse Dynamics based Energy Analysis and Simulation) of assessing the controllability of a building and its servicing systems. IDEAS allows confident (i.e. calibrated in SAP) predictions to be made regarding the impact of novel heating and renewable energy systems. IDEAS can be used as a dynamic sizing tool for a heating system in a building and can be used to benchmark control systems performance as it can represent near perfect control. The addition of an air source heat pump model to IDEAS is described. This allows for detailed analysis to be made of air source heat pumps in a SAP-compliant framework, taking into account the dynamic nature of the system efficiency and thermal capacity.Practical applications: ASHPs are still a relatively novel technology in the UK, yet it has been suggested they could play a significant role in efforts to de-carbonise the heating sector. However field trials have found performance varies widely from installation to installation. Whilst some of this variation is due to user behaviour, ASHP systems are also very sensitive to design and commissioning. Fundamental methodologies which can provide detailed analysis of ASHP performance, such as that presented in this article, could contribute to improving system design standards. This would ensure more installations achieve a good level of performance, boosting confidence in the technology.