Introducing ISEER Rating – Indian Seasonal Energy Efficiency Ratio

The Bureau of Energy Efficiency (BEE) has introduced a new star-rating methodology called Indian Seasonal Energy Efficiency Ratio (ISEER) for air conditioners. This methodology factors in variance in higher temperatures in India and rates air conditioners accordingly. Consumers can now purchase air conditioners with higher efficiency, leading to lower electricity bills.

World over, the method of defining energy efficiency of air conditioners is Seasonal Energy Efficiency Ratio (SEER). The basic theory behind SEER is that the temperature does not remain the same round the year. As there is seasonal variation of temperatures, there is variation in the amount of cooling required. Amount of energy (or electricity) required by an air conditioner to cool a room to 25 degrees (or any other standard temperature) is different when outside temperature is 30 degrees, in comparison to when the temperature is 40 degrees. Also, the usage (in hours per day) will vary as per the seasons.

So, ISEER denotes the ratio of the total annual amount of heat that the equipment can remove from the indoor air when operated in active mode to the total annual amount of energy consumed by the equipment during the same period. This is the ideal number to compare two ACs as your usage of an AC may vary, directly affecting the electricity consumption. Check the ISEER rating of the Inverter Air Conditioners

How is ISEER different?

The ISEER (Indian Seasonal Energy Efficient Ratio) rating standard was made mandatory from 2018. On the newly introduced ISEER rating standard, the existing EER star ratings brackets were revised. Also, keep in mind that ratings are different for Window and Split air conditioners. Given below are BEE defined, ISEER ratings valid from 1st January 2018 to 31st December 2019.

Remember that it’s not fair to compare the star ratings of a split air conditioner with a window air conditioner. For example, a 4 star window air conditioner will not have the same efficiency as a 4 star split air conditioner. Most manufacturers are reducing their Window ACs line-ups and focusing more on Split ACs, many of which are inverter based. The manner in which they function leads to better energy efficiency compared to non-inverter models.