What is star rating and electricity consumption

What is star rating and electricity consumption relation in air conditioner

What is BEE star rating?

What is star rating and how it helps us to understand the energy consumption a year of appliances? BEE (Bureau of Energy Efficiency) has set some standards for this rating and this rating keeps on changing every two years. Means any ac having 5-star rating two years back will not have 5-star rating this year unless ac manufacture matches the revised energy efficiency ratio.

How BEE star rating is calculated?

We must understand EER and ISEER value to understand the BEE star rating. We will see what the difference between EER and ISEER as well.

EER (Energy Efficiency Ratio) Value: This is used for non-inverter ac (Air conditioner). Non-inverter ac (Air conditioner) use fixed speed compressor.

EER = Amount of heat removed in an hour / amount of power supply in same hour.

The removed heat by ac is depend on room temperature, ambient temperature and humidity. So, it is calculated on ambient temperature (35⁰ C), humidity (50%) and indoor temperature (27⁰ C).

ISEER (Indian Seasonal energy efficiency ratio) Value: After introducing inverter ac (Variable speed compressor), the old method was not good enough to calculate the value. BEE has introduced new system for value calculation to overcome the problem. ISEER calculation is almost same as EER. Only difference is that it considers variable power consumption and seasonal temperature changes.

ISEER = Seasonal cooling load / Seasonal energy consume.

What those star ratings are for AC (Air conditioner)?

From above star rating table, we understand that split air conditioners are more efficient than window ac. 1-star split air conditioner is equivalent to 4-star window ac. While buying air conditioner EER value is more important.

Is this rating verified by BEE (Bureau of Energy Efficiency)?

Yes. BEE or its designated agency pick up one or two samples from manufacturing facility or warehouse and one or two samples from retail outlet. Total 3 samples are collected. Two samples are tested one sample is kept as an alternative in case any damage happen to one of these two samples.

Where can I see this value on appliances?

There is a label adhered or attached as tag on display front or on the front of unit. The sample label is as follows. Unit not on display, this label must be attached on the packaging exterior or may be attached on the unit when it is removed or must be provided as part of documentation to the customer.

 

You will get following information along with EER rating on the label. 1. Appliance/Type: 2. Brand/Model Name/Number/Year of Manufacturing 3. Capacity (kW) (Actual Tested) 4. Power (Watts) 5. EER (W/W) 6. Label Period 7. Variable Output Compressor (Yes/No) 8. Heat Pump (Yes/No)

 Is label design specified?

Yes. Not only the design, shape, size and colour as well. Material of label must be durable clipboard, if it is to be attached as swing tag or self-adhesive as per the dimension provide by BEE. These labels must be printed as per the following specification.

Tips:

Always go for higher BEE star rating. Better star rating means less operational cost due to less electricity consumption. Also look for label period.