In the development of modern HVAC equipment of particular importance is given to the problem of energy conservation. The amount of energy consumed by the equipment during the annual life cycle is one of the main criteria for decision-making when considering proposals submitted to tender. To date, a significant potential for energy efficiency is the development and establishment of climatic equipment, able to cover as precisely as possible the load schedule in constantly changing conditions
At the same time, the daily schedule of excess heat is also uneven pronounced maximum. Traditionally, chillers with capacity of 20-80 kW installed two identical compressors and make the two independent refrigerant circuits. As a result, the machine can operate in two modes at 50% and 100% of its rated capacity. The new generation of chillers with cooling capacity from 20 to 80 kW allows you to perform three-stage capacity control. In this case, the total refrigerating capacity is distributed among the compressors in a ratio of 63% and 37%.
The new generation of chillers both compressors are connected in parallel and operate on a single refrigerant circuit, that is, have a common condenser and evaporator. This arrangement significantly increases the energy conversion efficiency (KPI) of the refrigerant circuit when operating at part load. For such chillers at 100% load and outdoor temperature of 25 ° C KPE = 4, and at the 37% CPE = 5. Given that 50% of the time the unit is working with a load of 37% of this gives a considerable energy saving.
Microprocessor controllers are set for the effective implementation of new solutions in the chillers, which allow:
- control all the operating parameters of the equipment;
- adjust the set point temperature of the water at the outlet of the unit in accordance with the parameters of the outside air, process or commands from a centralized control system (supervisor);
- selects the optimal power control step;
- In the case of real need to quickly and effectively perform a defrost cycle (for heat pump models).
As a result, an automatic compressor to minimize the short-inclusions, optimize working hours of compressors and the adjustment parameters of the water leaving the chillers in accordance with real needs. As on average, it takes place during the day only 22 incorporating compressor while the compressor includes conventional chiller 72 times.
Another important advantage which enables the use of new chillers, is that eliminates the need for installation of bulky storage tanks and built into the body of the unit circulation pump eliminates the need for an additional pump station.
Energy-efficient gas compressor
As you know, for the accurate performance load curve of the chiller is very important type of used compressors. Traditionally, large capacity chillers used piston or rotary screw compressors. The reciprocating compressor has many moving parts and, consequently, low efficiency due to large frictional losses. In the operation of reciprocating compressors there is a high level of noise and vibration, as well as there is a need for their regular maintenance. Screw compressors, in turn, have a complex structure, and as a result, very high cost. Production of screw compressors is low-profit.
Service of such compressors consuming and requires highly skilled personnel. In recent years, the market of new type of compressor SCROLL appeared that lack specific deficiencies reciprocating and screw compressors. Scroll-compressors have a high energy efficiency, low noise and vibration, and require no maintenance. This type of compressors is simple in construction, is very reliable and, at the same time is inexpensive. However, performance Scroll-compressors usually does not exceed 40 kW.