What is Star Rating on AC ( Air Conditioner)? It is the most frequently asked question by any consumer about an Air conditioner or refrigerator. Today we will explain the complete guide of Star Ratings on AC so that you don’t face any problems while choosing your new Air conditioner. We have also made a dedicated Post on best AC in India 2020, which will help you select few best-sell ACs from a large variety of models available in the market.

Guys, whenever we go out to buy an AC, the salesperson suggests that we go for a 3-Star AC, 4-Star AC, or 5-Star AC as better the Star the rating more is the energy-efficiency of AC, which means you will have to bear fewer electricity charges. This energy efficiency, which is also called ISEER (Indian Seasonal Energy Efficiency Ratio) in scientific terms, can tell us how much electricity is consumed within an hour. This ISEER is always mentioned on the Star rating sticker so that you don’t have to search for it anywhere or don’t have to consult anyone for this. You can also find this in the below image.

Okay, let us talk about the calculations and begin with star Rating Sticker First. The stars are visible in the red stripe on the sticker, where more stars mean better energy efficiency. Next, you will find the EER ratio on the label, which is the AC’s actual energy efficiency ratio. The EER parameter ratio keeps on changing every year by BEE (Bureau of Energy Efficiency). The ERR ration keeps getting advanced each year, which means 3-Star or 5-star ACs bought in 2020 are more energy-efficient than AC purchased in the year 2016. The 3-Star ACs of 2016 are now counted in 1-star ACs because technology is getting advanced every year, and therefore ERR ration keeps on changing every year.

Now let us talk about the main point of how to calculate an electricity consumption of the particular AC that we are planning to buy. Guys, you need to understand that electricity consumption varies with various factors like the duration of AC usage, the temperature used like 22 degrees or 24 degrees, and the place where we live. Therefore, we are going to talk about standard electricity consumption without considering the various factors mentioned above.

If you look at the Star rating Sticker, you will find three things: **cooling capacity, Energy efficiency ratio**, and **power consumption**. These three parameters are required to calculate AC Electric unit usage. Let me clarify one thing: the cooling capacity of an AC is measured in Ton as we all know like 1 ton, 1.5 ton and 2 ton. However, the cooling capacity mentioned in the Star rating sticker is mentioned in Watts. To learn how to convert watts in Ton, please refer to our dedicated post where you can learn the convert Watts in Ton.

Now let’s calculate the unit consumption of an AC. Suppose the cooling capacity is 5220 watts (1.5 Ton), and ERR is 3.25 as it is a 3-Star AC, and power consumption is 1605 watts. The power consumption is calculated using the following formula: **COOLING CAPACITY/ERR = POWER CONSUMPTION. The answer comes out to be 1605 watts. **The 1 Unit = 1000 Watts, which means 1605 watts, is 1.6 Units power consumption per hour. If you use your AC for 1 hour, it will consume 1.6 Units of electricity per hour, excluding the factors discussed above. With this method, we can also calculate the power consumption of 1 star and 5 star AC.

If you want to check the maximum electricity consumption in an hour, I suggest you run your AC at the minimum temperature of 18 or 16 degrees for 1 hour continuously. The reason behind running the AC on minimum temperature is that if you try to run your AC on 24 or 26 degrees, then it will quickly achieve that temperature before 1 hour and the compressor will turn off automatically then you will not be able to find the actual electricity consumption in an hour.