Analysis of possibilities to utilize excess heat of supermarkets as heat source for district heating

Heat pump working fluid selection—economic and thermodynamic comparison of criteria and boundary conditions

“…Additional secondary aspects may be considered in the selection of the most promising fluids. Examples of more detailed screening evaluations are presented in (Mancini et al, 2018;Zühlsdorf et al, 2017Zühlsdorf et al, , 2018cZühlsdorf et al, , 2018aZühlsdorf et al, , 2018d. The selection of the working fluids should comprise a sufficiently large number of candidates and consider:…”

“…The income for the investment consists of the district heating supply, which is assumed to be sold at 40 €/MWh, while the electricity is bought at 120 €/MWh. The economic boundary conditions constitute a representative scenario and are aligned to Danish conditions (Energistyrelsen, 2017;Zühlsdorf et al, 2018d). The application offers an additional income by replacing the existing cooling facilities but since these costs are highly uncertain, they were omitted from the economical assessment.…”

“…Zühlsdorf et al have shown in different studies, e.g. (Zühlsdorf et al, 2018a), (Zühlsdorf et al, 2018c), (Zühlsdorf et al, 2018d) and (Zühlsdorf et al, 2017), that an integration of heat pumps into given boundary conditions yields more efficient solutions, when the integration process comprises the heat pump design and a simultaneous screening of the working fluid among pure and mixed refrigerants. The studies have shown that the potential performance increase from utilizing zeotropic working fluid mixtures varies according to the boundary conditions and can reach possible increases of more than 40 % (Zühlsdorf et al, 2018c), relative to the performance of pure fluids.…”

“…Another approach to evaluate the working fluids is fixing the minimum pinch point temperature differences in the heat exchangers. This approach was adopted in previous studies, (Zühlsdorf et al, 2017(Zühlsdorf et al, , 2018a(Zühlsdorf et al, , 2018c(Zühlsdorf et al, , 2018d, and it was found to be a suitable way of sizing the heat exchanger area while identifying fluids with a high thermodynamic performance. Other authors, e.g.…”

Operation of supermarket refrigeration units: a coupled district heating and electric network approach

“…refrigeration cycle) level, missing on the potential system integration aspects of these units. The authors of [20,21] have presented some work on coupling waste heat from supermarkets to DH, characterising supermarkets as a potential heat source for DHNs. However, these studies do not explicitly model the DHN or the control system governing such operation.…”