Energy efficient air conditioners are continuously being developed as the demand for them continued to increase as the fight to reduce global warming accelerates. Reduction in the power used by air conditioners will translate to a reduction in carbon footprint as most of our power utilities still use fossil fuel to generate the electricity.
The days of using ozone-friendly refrigerants since Montreal Protocol are already here and as a result, this hole above the Antarctica has been shown to be shrinking.
Ozone-unfriendly refrigerant such as R22 is no longer in production and although you can still purchase equipment with this gas through recycling process, it will eventually be replaced by other ozone-friendly refrigerants such as R407C, R410A and R32. These refrigerants have zero ozone depletion potential.
In general, the more efficient the equipment is, the more costly it is compared to the regular ones. Here are some steps that you can take when choosing energy efficient air conditioners to purchase.
1. Cooling Capacity
Determine the cooling capacity that is required of the room. A rough estimates of how to do this is provided here. Buying an oversize air conditioner is not a good choice as it is more costly and does not necessarily provide better comfort level.
2. Inverter Vs Non-Inverter
Choose an inverter model as it will be definitely more efficient than a non-inverter unit. The inverter compressor's rotation can be varied according to the requirements of the load hence the power savings is there.
On the other hand, the non-inverter compressor is only able to turn ON or OFF. It is not able to vary its speed according to the load. The frequent turning ON and OFF will consume more energy.
Choose also a DC inverter compressor as it is more efficient compared to the AC inverter.
Diakin, the company which specializes in HVAC industry has developed a reluctance DC motor of the compressors which have high strength neodymium magnets that are embedded in the rotating shafts of the compressors' motors. These magnets are 10 times more powerful than the normal ferrite magnets hence providing a more superior torque for the compressors, making Daikin the technology leader in this field.
3. COP, EER and SEER
Check the brochures for the efficiency of the model. Every model will have different values and it also varies with different manufacturers.
COP is the ratio of the cooling capacity(W) vs the power input(W). The higher the value, the more efficient it is as it is able to provide more cooling for the same power input.
If it is not given, do your own calculation. For ease of cooling capacity conversion, 1W=3.4121 Btu/h. Choose a higher COP model.
EER is the ratio of the cooling capacity(Btu/h) vs the power input(W). As with COP, choose a higher EER rating and the unit will consume less energy for the same capacity.
SEER is the ratio of the total cooling that the equipment is able to provide over the entire season (Btu) Vs the total energy(Watt-hours) consumed. SEER is more accurate as it takes into consideration the start-up and shut-down cycles of the air conditioner. Choose a higher value for energy efficient air conditioners.
4. Energy Star Rating
Every country has its own energy ratings for the model of the air conditioner that has been tested.
Choose one that has the highest rating as this would mean that the unit is much more efficient compared to another lower star rating.
5. Infra-Red Sensor
Some manufacturers such as Daikin have built-in infra-red sensor that is able to detect the presence or absence of the occupants in the room. If it does not detect any movement for a certain period of time, it will adjust the set temperature higher automatically to reduce the temperature in the room. This will help to save your electricity bill.