Any thermal pump during operation has various value of development of energy and electricity consumption. These indicators depend on many factors which in one way or another influence operation of the thermal pump.
Overall performance of the thermal pump is estimated by COP indicator – effectiveness ratio of thermal transformation.
COP = Q/E, where Q – quantity of developed thermal energy of kWh. E-quantity of the consumed electric power of kWh. This parameter is defined by producers for concrete temperatures, vlazhnost (for updatings air water / воздух-воздух) and at the specified expenses of environments. The capacity consumed and developed by the thermal pump depends on pressure of freon from both parties of the compressor (absorption and forcing). At a big difference between pressure – overall performance of the thermal pump and heatproductivity decreases and on the contrary. By such principle the majority of thermal pumps presented in the market works. To obtaining higher efficiency of thermal transformation apply various methods. Methods it is possible to carry to these:
- Use of electronic throttles of a channel. Replacement of a mechanical throttle by the electronic – allows to support more precisely necessary pressure and as allows to receive at the same modes for 5-15 % more thermal capacity with the best efficiency
- Use of compressors with additional injection of steam. Use of such compressors is accompanied by embedding in a contour of the additional heat exchanger in which, the freon stream from the condenser is divided, and its part moves directly in the compressor. Thus there is an increase at 10-30 % of development of thermal capacity and efficiency of thermal transformation. Use of compressors of this kind allows to expand a range of temperatures at which operation of the thermal pump is possible. In particular, for thermal pumps air/water admissible air temperature falls to-20 wasps, thus it is possible to heat up a water contour till 55-60 wasps with peaks to 65 wasps.
For the description of overall performance of the thermal pump the indicator of seasonal efficiency of thermal transformation (HSPF) is used , where QHi – quantity of developed thermal energy in a month (in кВт*ч); EHi – quantity of the consumed electric power in a month (in кВт*ч); n-number of months of a heating season in a year. According to the European instructions for definition of degree of economy for all heating period this indicator is used. In it thermal development and energy consumption during the season is considered by all sources of heat: the thermal pump, the solar collectors, duplicating sources of heat (coppers) etc. which are included into uniform system of a heat supply. The this indicator, the less than financial operational expenses during the season is higher.