Gas vs Electric Hot Water in Sydney: Choosing the Right System for Your Home

When your hot water system dies, the biggest decision isn't always repair-versus-replace — it's gas versus electric. Both heat water fine, but they differ in running cost, up-front price and whether you're even allowed to install them. Here's an honest Sydney guide to choosing between them.

Where gas and electric hot water differ

A gas hot water heater burns natural gas (or LPG) to heat water, usually in a storage tank or on demand through a continuous-flow unit. An electric heater uses a heating element and a storage tank. In practice, both give you hot showers — the difference is how much each sips in running costs and how involved the installation is. In Sydney, many older homes have gas already plumbed in, while newer builds and apartments often default to electric.

Running costs: gas is usually cheaper to run

As a rough guide, gas hot water is typically cheaper to run than a standard electric storage heater in Sydney, because gas is billed per megajoule and heats water quickly. On demand or continuous-flow gas is especially efficient — it only heats water as you use it, so there's no standing heat loss from a tank. An electric storage heater is simpler but less efficient on running cost. Exact numbers depend on your usage, tariff and gas connection, so treat any figure as indicative.

Up-front price and installation

Electric storage units are generally the cheapest to buy and the simplest to install — many plumbing jobs can swap one in a few hours. Gas units cost more up front, and if you don't already have a gas connection, adding one means laying gas pipework and getting a gas fitter involved, which pushes the total up. Continuous-flow gas units sit at the higher end. Always get a quote that includes the heater, materials, labour and any compliance work.

What's available where you live (Sydney rules)

Gas availability varies by suburb and a lot of new Sydney developments are all-electric, sometimes driven by planning rules or the network itself. Before you commit, check whether there's a gas line to the property or whether the local network and council rules allow one. In many all-electric or apartment complexes gas isn't an option at all, which makes an electric — or a heat pump — the practical choice.

Heat pumps: the rising middle option

Worth knowing: heat pump hot water systems are electric but use ambient heat to warm the water, so they can run much more efficiently than a standard electric tank. They cost more to install and take up more space, but they can dramatically cut running costs. For a Sydney home wanting efficient electric hot water, a heat pump is often the smarter electric choice than a conventional tank.

How to decide, then who to call

A simple decision frame: if gas is available and you want low running costs, a continuous-flow gas unit is hard to beat. If you're in an all-electric area or planning to go all-electric, a heat pump is worth the extra up-front. If you just need a cheap, quick swap on a tight budget, an electric storage tank does the job. Whatever you choose, a licensed plumber (and for gas, a gas fitter) should install it and certify the work.