Usually natural gas is the cheapest way to heat water, followed by electricity, with propane being the most expensive.
The best budget option if gas is not available or is expensive is a heat pump water heater, but there are considerations based on your climate for where they can be located to be efficient.
The type of water heater you choose will have a decisive impact on your monthly utility bill. Natural gas is a cheap source of energy, which means that a natural gas water heater is relatively inexpensive to run.
A combi boiler is used both to heat water and your home. They're energy-efficient because although they're on all the time, they only produce hot water when it's needed, thus helping to reduce your bills.
Heat pump water heaters move heat from one place to another instead of generating heat directly for providing hot water, resulting in high efficiencies and significant cost savings. Solar water heaters use the sun's heat to provide hot water and also save money on energy bills.
Type of Hot Water Heater
Even when capacities are identical, traditional electric storage hot water systems are typically the most affordable option on the market. These systems have been widely used for decades and are often considered a budget-friendly choice for households.
Water heating is the second largest energy expense in your home, accounting for about 18% of your utility bill. To conserve hot water, you can fix leaks, install low-flow fixtures, insulate accessible hot water lines, and purchase an ENERGY STAR certified dishwasher and clothes washer.
Electric water heaters/Hot water heat pumps
Electric water heaters generally have lower running costs and lower emissions than gas water heaters. Hot water heat pumps are the most efficient option, requiring significantly less electricity to run than traditional electric water heater systems.
If you keep your water at a high temperature all the time, you will lose more heat to the environment even if the cylinder is well insulated. Your water heating costs will increase in direct proportion to the average temperature of the cylinder over the day. You will end up paying for more energy as a result.
Tankless Water Heater Cons
Installing a tank-style water heater typically costs about $900, while the average cost to install a tankless water heater can exceed $3,000. Limited Flow Rates: Reduced flow rates can lead to poor heating efficiency and low-temperature water.
Tankless water heaters are able to provide endless hot water because they heat your water on-demand instead of from a tank (which can eventually run out of hot water).
Are electric water heaters expensive to run? According to the Department of Energy, the average American household spends between $400 and $600 each year on water heating alone. This cost will vary depending on the electricity rates in your area and your water heating unit's efficiency.
It's generally much cheaper to heat water using your central heating system, rather than using electricity with an immersion. The exception might be during the summer, when you have your central heating turned off, or if you have an old inefficient boiler.
Set too high, or at 140ºF, your water heater can waste anywhere from $36 to $61 annually in standby heat losses. Additional savings will be realized by the lower temperature for consumption (from water demand or use in your home, such as clothes washing, showers, and dishwashing). These may amount to more than $400.
Generally, your boiler's flow temperature should be between 60°C and 70°C. If you were to set it to a higher temperature, it runs the risk of scalding with the water being too hot for use. Beyond that, it would make your boiler less efficient.
Heat pump. Heat pump water heaters are highly efficient and use 30% of the energy of a conventional electric hot water system. These systems use a refrigeration cycle to extract heat from the air to heat the water.
How Tankless Water Heaters Work. Tankless water heaters heat water instantaneously without the use of a storage tank. When a hot water faucet is turned on, cold water flows through a heat exchanger in the unit, and either a natural gas burner or an electric element heats the water.
Usually natural gas is the cheapest way to heat water, followed by electricity, with propane being the most expensive.