Parametric modelling of domestic air-source heat pumps

Abstract

A new domestic air-source heat pump model is proposed which can be parameterised either from field data, experimental data or manufacturers' standard rating data. The model differs from the much more prevalent system-side regression models for these types of heat pumps in that it operates on refrigerant-side variables. This makes it more suited to detailed performance analyses of heat pumps in service. Because both field data and manufacturers' data can be used for parameterising the model, it can be used to investigate problems associated with the building performance gap where a heat pump is used. A new type of efficiency-based compressor model is developed which enables compressor performance to be directly compared with alternatives and a model of defrosting is included by introducing a new defrost discounting term. Results tested using data from a field monitoring site and from a laboratory installation show good predictive behaviour by the model especially at low source air temperatures. When the model is fitted using manufacturer's standard rating data, a performance gap is evident when compared with the model fitted to field data but the gap is generally nominal.

Techno-economic assessment of cascade air-to-water heat pump retrofitted into residential buildings using experimentally validated simulations

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“…To build the performance map and a defrost model, the recorded raw data regarding the heat pump from three monitoring sessions mentioned in section 2.3 were processed using R (programming language) software [44] and the suggested procedure of Underwood et al [45], as explained as follows:…”

Predictive Thermal Relation Model for Synthesizing Low Carbon Heating Load Profiles on Distribution Networks

“…• Physical model that captures a detailed heat pump/heating system but with limited capture of time of use effects across a population [12] These approaches all feature their own specific advantages and disadvantages depending on the specific area of study.…”

Hybrid Adsorption-Compression Systems for Air Conditioning in Efficient Buildings: Design through Validated Dynamic Models

“…. m re f = m sorb dw dt (10) Uptake derivative depends on adsorption kinetics. A common approach to define is through the Linear Driving Force (LDF) [37,60,62]:…”

“…Indeed, as already reported [9], the renewable heating and cooling sector is considered as a "sleeping giant" that, if properly promoted, could further support the diffusion of renewable sources especially in the residential and commercial sector. The heat pump technology is by definition able to exploit renewables, e.g., directly from ambient air [10] or from geothermal heat sources [11]. Nevertheless, the share of renewables guaranteed by standard heat pumps is limited, since they are usually driven by electrical energy.…”