HOW SMALL COULD A 'SMALL' HEAT PUMP BE ? THE RELATION BETWEEN BUILDING AND HEAT PUMP PERFORMANCE

摘要

The first and foremost duty of a heat pump is energy efficient heating of buildings with highest possible COP. However, heat pump and building are interacting and the simple call for "good COP" does not apply.Modern residential and commercial buildings must be equipped with a ventilation system to maintain at least an acceptable indoor air quality in air tight low-energy houses. A simple energy balance tells that heat pumps with a high COP need an excellently insulated building and badly insulated buildings need a heat pump with a low COP. This may seem somehow paradox but is a fact of the interference between the building energy demand and the heat pump.The findings of this case study are generally applicable and form some kind of "First Law for Heat Pumps”, which reads in short: "Before considering a heat pump, first insulate the building very well!". Simple thermodynamic evidence calls for this undertaking.