Difference between Gas and Electric HWS

    Educational Tip

    Difference between Gas and Electric HWS

    This is the question most frequently asked by homeowners.  Heat pumps, Solar hot water and Instant hot water are also options currently on the market.   Both electric and gas have their fair share of pros and cons so it’s more about finding the right water heater that meets your needs. Hot water accounts for approximately a quarter of a household’s energy consumption and cost, so the right choice is crucial. 

    So how do they each work – An electric water heater is a tank that heats water with high voltage electric heating rods that run vertically through the tank, starting at the centre and radiating outward. 

    Whilst a gas water heater is a tank that heats water from a gas fired burner located at the bottom of the tank so hot water starts at the bottom and rises upward where it is drawn off the top by a discharge tube.

    About Electric:

    Lower initial cost - Because they don’t require gas vents, electric water heaters are usually less expensive to purchase and install.

    Ease of installation - Electric heaters can be installed in locations in which it would be difficult or impossible to install a gas vent.

    Safety - Electric water heaters don’t require combustible fuel, which can leak or explode. They also don’t have pilot lights that can ignite flammable vapors or produce carbon monoxide, which can backdraft into occupied spaces.

    Traditionally the most popular and inefficient – electric systems are expensive and inefficient to run because they are usually operating a lot.  Although off-peak tariffs and clean energy have made them cheaper to run and better for the environment.

    About Gas:

    They are cost effective – Because gas is currently cheaper than electricity, they have cheaper running costs, an estimated 33% cheaper. You don’t need to be concerned with off-peak tariff times but do need to ensure your gas bottles don’t run out.

    Cost a little more upfront – Whilst there running costs are usually more cost effective, they can cost a little more at the checkout.  Gas units are more expensive and switching from electric to gas will mean new gas lines will also need to be installed by a qualified gas fitter.

    They are energy efficient – Gas hot water systems are more energy efficient as they heat water faster and don’t need to run as often as the electric models.  Typically, a continuously burning pilot flame ignites the main burner when needed. Since they don’t need as large a storage tank the actual systems are also smaller.


    Some questions to consider when choosing between electric and gas –

    How long are you planning on living there? 

    How many people is the unit servicing?

    What unit is currently operating?

    And if you still can’t decide then don’t hesitate to contact your local qualified plumber to get some friendly advice.