There is a lot of confusion in the domestic air conditioning market as to what Star rating is best suitable for a particular type of use! Simply put forward the higher the star rating higher are the savings on electricity bills.
At the same time higher the star rating higher are the equipment costs.
This parameter is granted by the Bureau of Energy Efficiency (BEE) Ministry of power Government of India
The energy efficiency of the air conditioning equipment is tested in laboratory as per IS standards to determine its energy efficiency.
It’s a ratio of cooling capacity or amount of heat removed (measured in Watts) to rated Electrical consumption (measured in Watts) for a particular capacity and type of the equipment, hence higher the ratio value more the savings on electrical consumption
An Air conditioner with cooling capacity of 4800 Watts has a rated power input of 1370 Watts (both these values are disclosed by the equipment manufacturers in their brochures or technical specifications)
Energy Efficiency Ratio = Cooling capacity / Electrical consumption
These ratio values are tabulated by BEE applicable for two years. Present STAR ratings provided for Split type Air conditioners are for a period from 1st Jan 2016 to 31st Dec 2017
|STAR Level||Energy Efficiency Ratio|
Here you will note a 30% efficiency difference between a 1 Star rated and 5 Star rated Air conditioners which is proportional to the energy savings!
Now to choose the air conditioner for a particular application the following factors needs consideration:
- Duration of use
- Day use / Night use
- Cost difference between models of various star ratings
For domestic use and in colder areas where the air conditioner would be used only during nights or say less than six months a year 3 or 4 star AC would just be fine.
For continuous use, commercial establishments – highest star rating equipment is highly recommended as the savings on electricity bills would negate the initial cost difference within a few months.