When it comes to water heaters, users always wonder how much it would affect their electricity bills. Since water heaters are effectively heavier appliances, they also do take a lot of power to function. However depending on the capacity and the energy stars of the appliance, the power consumption of geyser varies. So, how do you calculate the power consumption of a water heater? Let us get into the details shall we?

First, you need to understand that there are a few things that dictate how much energy your water heater will consume. This includes not only the capacity, but also the brand, the make, and most importantly the star rating of the water heater.

How to Calculate Geyser Power Consumption?

So, geysers come in a variety of sizes and capacities. A bigger geyser will no doubt take more power to run and therefore cost more in terms of electricity bills. But, how to calculate your geyser’s power consumption to get an estimate on how much you would be spending? Let us take a look at that.

To calculate the power consumption of geyser, you need this formula to figure it out.

Power consumption (kWh) = Energy consumption of the geyser x Operating hours/day

So, if you have a higher capacity geyser from one of the best instant water heater brand in India, you would find it takes more energy to function when compared to a smaller geyser. Also, if you tend to use a geyser for longer hours per day, that would also result in higher electricity bills.

There are two other aspects of a water heater that would dictate how much power it takes to run. The power rating measured in Watts, explains how much energy it consumes per hour. For example, a geyser rated 2000 Watts would consume around 2kWs of electricity per hour of usage.

Therefore, if you have a 2000W geyser with a capacity of 25 liters, and you use it for an hour everyday, using the formula above, the total power consumption would come out to around –

Power Consumption (kWh) = 2000W x 2hr

Which equals = 4000Wh = 4kWh per day

With this result, we can now calculate how much money you would be paying on a daily basis to run a 25L 2000W geyser.

Say your cost per unit, or cost per kWh, is Rs. 5. Then by calculating, you would be paying –

4kWh x Rs. 5 = Rs. 20 per day

Now, you can easily calculate how much it would cost on a weekly, monthly, and yearly basis. Also, instant water heaters and storage water heaters function differently and use a different amount of electricity. Instant water heaters take slightly lesser electricity since their function is instantaneous. That said, if you keep an instant water heater running for long enough, it eventually comes in par with the electricity usage of a storage water heater.

Here is a table for you to easily understand how much you would be spending overall. This information is about a 2000W geyser that runs for about 2 hours everyday.

Geyser Power Consumption (Runtime 2 hours/day)Total (Wh)kWhCost (Rs. 5 per unit)
Hourly20002Rs. 10 per hour
Day40004Rs. 20 per day
Month120000120Rs. 600 per month
Yearly14600001460Rs. 7300 per year

Obviously there will be differences here depending on the Wattage of your particular geyser, along with varying electricity costs around the country. Using this formula can really help you get an estimate of how much you would be paying for your hot water on a yearly basis.

While this is great for estimating how much electricity it will use, there are obviously other aspects to it as well. For example, if your geyser is energy rated 5 stars, you might be able to save a bit on power as compared to a 2 star rated water heater. For appliances with energy star ratings above 3, it means the model is energy efficient and is capable of saving electricity.

Also read: Best Geysers Guides, Reviews & Comparisons

Factors Affecting the Power Consumption of Geyser?

Now, there are a few things that can affect the proper functioning of the best water heater for home, which amounts to increased electricity bills throughout. Here are a few things that affect how well your geyser functions and how much electricity will it use when functioning.

  • How frequently you use your geyser
  • The condition of your geyser
  • The brand of your geyser
  • The energy star rating of your geyser
  • The quantity of hot water you use on a daily basis

How to reduce Power Consumption of Geyser?

Now, the thing is, you can do your part to make sure your geyser does not take a lot of electricity. Obviously, you do not have complete control over it, but you can do a little bit to make sure you use it as effectively as possible.

  1. Select a geyser with a thermostat: There are tons of newer models of geysers in the market that come with a thermostat. While you might not find this feature in older models, a lot of the newer ones allow you to control the temperature of the water inside. This is especially helpful if you live in a place with varied climates. If you do not want really hot water during the summers, you can set the temperature to low which makes sure it does not use a lot of power. Similarly, you can also control the temperature for the winters, making sure you get the exactly right temperature without spending more electricity on it.
  2. Minimize usage: When it comes to usage, you can reduce how much you need on a daily basis. Reduce the amount you need for bathing, or washing clothes, or even doing the dishes. This will certainly amount to lower electricity bills on the long run. Taking bucket baths allows you to effectively use the hot water without any wastage.
  3. Choose a high energy rated geyser: Buying a geyser with a higher energy rating can also help you reduce heavily on electricity bills. Ideally, you should purchase a 5 star rated geyser to save a ton on electricity bills. However, if you do not have the budget, anything above 3 stars is worth trying out.
  4. Choose the right capacity: Buying a larger geyser is just as demanding as buying a smaller geyser. The thing is, in a bigger geyser, more energy is required to heat the water while the entire thing might not be utilized in the first place. Similarly, if you get a smaller geyser according to your needs, you might find yourself keeping it on for a longer time to help complete your requirement for hot water. Get the right capacity according to your needs, refer to geyser sizes to purchase the right capacity of geyser.
  5. Use the timer: Some models even come with a timer. Using that, you can easily set a time limit on your geyser which shuts it off once the timer reaches its limit. This is especially useful in places with varying climate since you might not need a lot of hot water in a certain time period as compared to others.
  6. Maintenance: If you do not properly maintain your water heater, it will obviously take more time and electricity to heat water. The element inside a geyser deteriorates over time, which means if you do not get it replaced, your geyser will automatically start costing you more in terms of time and electricity. Make sure you do an annual maintenance run on your geyser to allow it to run properly.

Frequently Asked Questions (FAQs)

How much unit does a geyser consume?

On an average, a normal 20L-25L water heater or geyser consumes around 2 units, or 2kWh of electricity on a daily basis. This will obviously be lower if you have a smaller geyser, and more if you have an older, bigger, or less energy rated geyser.

How many hours does a geyser run per day?

Depending on your use, an average family uses a water heater for around 2 hours per day. If you live in colder regions, you will obviously use it for longer. Similarly, the usage of geysers is reduced in the summers, and increased in the winter time. If you have a large family, instead of keeping your geyser on for longer, try buying a bigger geyser instead.

Which geyser is best for 4 member family?

For a family of 4, we suggest a geyser with capacity around 25L. This is perfect for most families, but you should be getting a higher capacity if your hot water usage is more. If you live in colder regions, you might need hot water for everything from bathing, to washing clothes, and doing the dishes. In this scenario, get a water heater with a higher capacity.

At what temperature must a geyser be set?

The ideal temperature for a geyser is around 55°C for warmer regions. If you live in colder places, we suggest setting the temperature to around 60-65°C.


When it comes to the power consumption of geyser, there are literally a lot of things you would need to look into. From energy star rating, to the capacity of the geyser, how much usage it sees, and how much maintenance it gets. Using a water heater is easy, but effective usage is somewhat tricky to say the least. As a user, you would have to keep in mind a few things to make sure you get the most out of your geyser, while not paying a fortune to keep it running.

We have suggested a few pointers to help you reduce the electricity usage of your geyser. Finally, we suggest thorough maintenance to make sure your geyser runs as effectively as possible for as long as possible.