How Much Does an Immersion Heater Cost to Run?

Immersion heaters are a popular choice for heating water in households and industrial settings. However, many people are unaware of how much it costs to run an immersion heater.

The cost of running an immersion heater can vary depending on several factors, including the size of the heater, the amount of hot water used, and the cost of electricity in your area.

The average cost of electricity in the UK as of July 2023 is £0.30 per kWh (including VAT). Based on this rate, it can be expensive to heat water with electricity, especially when compared to gas or oil.Immersion heater running cost

Leaving your immersion heater on all the time can also be a waste of energy and money. In this article, we will explore how much it costs to run an immersion heater and provide tips on reducing your energy bills.

Factors Affecting the Immersion Heater Running Cost

The running cost of an immersion heater depends on several factors. Here are some of the factors that affect the running cost of an immersion heater:

1. Power Rating

The power rating of the immersion heater is one of the most significant factors that affect the running cost. The higher the power rating, the more electricity the heater will consume, resulting in higher running costs.

On average, immersion heaters consume around three kilowatts of electricity per hour, which translates to running costs of approximately 50p an hour.

2. Frequency of Use

The frequency of use is another factor that affects the running cost of an immersion heater. If the heater is used frequently, the running cost will be higher.

For example, if a family of four uses an immersion heater for two hours a day, the energy bills could total £360 plus per year.

3. Insulation

The insulation of the hot water tank is also a factor that affects the running cost of an immersion heater. If the tank is well insulated, it will retain heat for longer, reducing the need for the heater to be switched on.

On the other hand, if the tank is poorly insulated, the heat will escape quickly, requiring the heater to work harder and consume more electricity.

4. Tariff

The tariff of the electricity supplier is another factor that affects the running cost of an immersion heater. The cost of electricity varies depending on the supplier and the tariff.

Choosing a supplier and a tariff that offers competitive rates is essential to keep the running costs low.

5. Size of the Tank

The size of the hot water tank is also a factor that affects the running cost of an immersion heater. A larger tank will require more energy to heat, resulting in higher running costs.

It is essential to choose a tank size that is appropriate for the household’s needs to keep the running costs low.

In summary, the running cost of an immersion heater depends on several factors, including the power rating, frequency of use, insulation, tariff, and size of the tank.

To keep the running costs low, it is essential to choose an immersion heater that is appropriate for the household’s needs, well insulated, and connected to a tariff with competitive rates.

Average Cost of Running an Immersion Heater

An immersion heater is an electric appliance that heats water in a storage tank. It is often used as a backup water heating method or in situations where a gas or oil boiler is not available.

However, the cost of running an immersion heater can be quite high, and it is important to understand the average cost of running one.

According to various sources, the average cost of running an immersion heater is around £0.50 per hour. This cost is based on the assumption that the immersion heater uses around three kilowatts of electricity per hour.

Therefore, if you run your immersion heater for two hours a day, you can expect to pay around £360 per year.

It is important to note that the cost of running an immersion heater can vary depending on several factors, such as the size of the tank, the efficiency of the heater, and the cost of electricity in your area.

For example, if you have a larger tank, you may need to run the immersion heater for longer periods, which can increase your energy bills.

To get a more accurate estimate of the cost of running your immersion heater, you can use an online calculator or consult with a heating engineer.

Additionally, you can take steps to reduce your energy bills by using a timer to control when your immersion heater is switched on and off, insulating your tank to reduce heat loss, and choosing a more energy-efficient immersion heater.

Overall, while immersion heaters can be a convenient and reliable backup water heating method, it is important to be aware of the average cost of running one and take steps to reduce your energy bills.

Cost Comparison: Immersion Heater Vs. Other Heating Systems

When it comes to heating water, there are several options available, each with its advantages and disadvantages. In this section, we will compare the cost of running an immersion heater with other popular heating systems.

Gas Boiler

Gas boilers are a popular choice for heating water in many households. They are efficient and can provide hot water on demand. However, they require a gas supply and installation can be expensive.

The cost of running a gas boiler can vary depending on the size of the boiler and the amount of hot water used. On average, it can cost around £250-£350 per year to run a gas boiler for hot water.

Electric Boiler

Electric boilers are another option for heating water. They are easy to install and can be used in areas where gas is not available. However, they are generally less efficient than gas boilers and can be expensive to run.

The cost of running an electric boiler can vary depending on the size of the boiler and the amount of hot water used. On average, it can cost around £500-£700 per year to run an electric boiler for hot water.

Solar Water Heating

Solar water heating systems use energy from the sun to heat water. They are environmentally friendly and can be cost-effective in the long run.

However, they require a significant initial investment and may not be suitable for all households. The cost of running a solar water heating system can vary depending on the size of the system and the amount of hot water used.

On average, it can cost around £100-£200 per year to run a solar water heating system for hot water.

Heat Pump Water Heating

Heat pump water heating systems use electricity to transfer heat from the air or ground to heat water. They are energy-efficient and can be cost-effective in the long run.

However, they require a significant initial investment and may not be suitable for all households. The cost of running a heat pump water heating system can vary depending on the size of the system and the amount of hot water used.

On average, it can cost around £300-£500 per year to run a heat pump water heating system for hot water.

In conclusion, the cost of running an immersion heater for hot water can vary depending on the size of the heater and the amount of hot water used.

However, compared to other heating systems, immersion heaters are generally more cost-effective to run. It is important to consider all options and choose the system that best suits your needs and budget.

Energy Efficiency Tips for Immersion Heaters

Immersion heaters are known to consume a significant amount of energy, which can result in high electricity bills. To help reduce energy consumption and costs, here are some energy efficiency tips for immersion heaters:

  • Insulate the water tank: Insulating the water tank can help reduce heat loss, which means the immersion heater won’t have to work as hard to maintain the desired water temperature. This can result in lower energy consumption and lower electricity bills.
  • Use a timer: Using a timer to control when the immersion heater is switched on and off can help reduce energy consumption. For example, setting the timer to switch the immersion heater off during the day when no hot water is needed can help save energy.
  • Take shorter showers: Taking shorter showers can help reduce the amount of hot water needed, which means the immersion heater won’t have to work as hard to heat the water. This can result in lower energy consumption and lower electricity bills.
  • Use a lower temperature setting: Setting the immersion heater to a lower temperature can help reduce energy consumption. For example, setting the temperature to 60°C instead of 70°C can help save energy.
  • Consider a solar water heating system: Installing a solar water heating system can help reduce energy consumption and costs. Solar water heating systems use energy from the sun to heat the water, which means the immersion heater won’t have to work as hard to maintain the desired water temperature.

By following these energy efficiency tips, it is possible to reduce energy consumption and costs associated with immersion heaters.

Conclusion

In conclusion, the cost of running an immersion heater can vary depending on factors such as the size of the heater, the amount of hot water needed, and the energy efficiency of the heater.

On average, an immersion heater will use around three kilowatts of electricity per hour, which can lead to average running costs of 50p per hour.

This means that if a household needs to have their immersion heater switched on for at least two hours a day to ensure the water is hot enough, energy bills totaling £360 plus are to be expected.

It is important to note that leaving an immersion heater on all the time can be a waste of energy and money. Therefore, it is recommended to only use the heater when hot water is needed and to turn it off when not in use.

To reduce the cost of running an immersion heater, it is also recommended to use a well-insulated heater to ensure that water is kept warm for several hours after the system is turned off.

Additionally, using an immersion heater in conjunction with a timer can help to reduce energy consumption and costs.

Overall, while an immersion heater can be a convenient and effective way to heat water, it is important to consider the cost of running the heater and to take steps to reduce energy consumption and costs where possible.

Related: What to do if you accidentally leave an immersion heater on.

About Eng. Nelson K.

Nelson is a Chemical and Process Engineer with vast theoretical and practical knowledge of Thermodynamics, Heat Transfer, and Mass Transfer.