Refrigerants and refrigeration systems have to be modified in order to address environmental requirements related to technical progress. These changes provide equipment manufacturers and practitioners with opportunities to better meet the needs of their customers. These needs have also been changing quite a lot, in particular in terms of:
· Humidity control: it is difficult to control both temperature and humidity. Nevertheless, there is increasing demand in this field. This is the case of the following in particular: * food preservation, namely chilled food, flowers and in display cabinets, * plant and processing rooms, * all air conditioning systems, where humidity control has led to choosing temperatures that are far too low in many cases, with discomfort and high energy consumption as consequences.
· Hygiene: requirements related to hygiene have become increasingly stringent in the food sector as well as in air conditioning.
· Reliable cold chain: in particular during transport, at interfaces, etc., with the need for monitoring, recorders and/or integrators.
· Energy savings: in relation to economic efficiency as well as with regulatory requirements about global warming. a lot of progress can be achieved in air conditioning design for example. The IIR Congress in Sydney will focus on this point in particular.
~Naveed Ahmad A, Production Engineer, Sahiwal, Pakistan
The Energy efficiency and low maintenance over the lifetime of a compressor would be the dominating factor in today's selection of hermetically sealed compressors. The commercial refrigeration sector, while still using hermetically sealed piston compressors on small applications, is drifting towards the Scroll type compressor for medium to large type chill temperature applications. Scroll technology is very efficient on medium refrigeration and Air-conditioning applications with low noise levels and can be started with very low inertia because they remain unloaded during the Off period. They are also lightweight for the amount of power they deliver and have very few mechanical parts. There is also the option of capacity control on Scroll compressors that allow them to run at reduced capacity on larger applications when the work load conditions fall in demand. (A) rated air-conditioning systems are generally fitted with hermetically sealed Rotary type, Inverter driven compressors for capacities up to 10.00 KW and run on R410a refrigerant gas. This design of the motor has enhanced the power output of these new compressors which are delivering very high COP's which make them the more chosen type for all new split air-conditioning & heatpump manufacturing companies.
~Engineering, Design, Dublin, Ireland
I think the biggest driver of compressor design comes from developments in refrigerants. New, higher-pressure refrigerants that are better for the environment necessitate materials and processing improvements that improve the strength of compressor components. Another important push for new compressor technologies is the eternal quest for improved efficiency.
~Justin Chamberlin, Lab Engineer, La Crosse, WI
The use of a subcool valve in combination with scroll compressors in the refrigeration process to obtain quick energy efficient temperatures. Eliminating the "Hunting" of TEV superheat systems.
~Pieter D, Design, service and support, Heidelberg, RSA
Efficiency of the drive motor is the most important. A simple dc drive motor with high efficiency and minimum electronic controls.
~Chris A, Engineer, Nicosia, Cyprus
Automatic PLC based control system for variable load operation. Adaptation of HFC refrigerants for vapor compression system.
~P L Sahu, Engineer, Visakhapatnam, India