Earth Notes: General Bibliography (vocale2014influence)
General public bibliography for EOU and related research. #bibliography #dataset
- [vocale2014influence] Vocale, Pamela and Morini, Gian Luca and Spiga, Marco Influence of outdoor air conditions on the air source heat pumps performance (accessed ), Elsevier, , Energy Procedia, volume 45, doi:10.1016/j.egypro.2014.01.070, article/pages 653–662, copyright Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported, PDF (article) (BibTeX).
abstract
The purpose of the present work is the investigation of the effect of the outdoor air temperature and relative humidity on the performance of an air heat pump, when the reverse-cycle defrosting is considered. The frost formation process has been analyzed by developing a simplified model which relates the number of defrost cycles to the outdoor air conditions. Moreover the energy consumption due to the defrosting has been taken into account in the evaluation of the heat pump performance. The results, carried out for many Italian sites, point out that the outdoor air conditions play an important role in determining the amount of defrost cycles; however the frost formation is mainly affected by the relative humidity. The analysis highlights also that the defrosting contribution on the heat pump performance is not negligible when the heat pump that operates in wet weather, although cold; in these conditions the hourly COP may be reduced by up to 20%. However, this effect becomes less relevant, but not negligible, when the seasonal heat pump performance is evaluated; the maximum decrease of SCOP, observed for the all analyzed cases, is less than 13%.
note
[In Italian cities, ASHP COP penalties of up 0.4 when including the impact of defrost cycles. Quote: "The numerical analysis points out that both temperature and relative humidity of the outdoor air affects the frost formation process; however the relative humidity plays a leading role in determining the amount of frost that can be accumulated. ... The numerical results highlight that the monthly average of the COP can be reduced by up to 17% when the heat pump operates in sites in which the values of air relative humidity are very high (RH>80%) and the outdoor air temperature is within the range 0-6°C during the winter for many hours."]