Electric hot water is the cheapest system to buy and install, and for the many homes across Perth's newer northern estates that have no gas connection, it's often the default. The trade-off is running cost — which is exactly why correct sizing and the right tariff matter so much.
Storage vs instantaneous electric
Electric storage
A tank of water kept hot by an element. Simple, reliable, available in sizes from 25L to 400L+. This is what most Perth homes have. Can run on a standard tariff or a cheaper off-peak tariff.
Instantaneous electric
No tank; heats on demand. Compact and efficient for small usage points, but most WA homes need a three-phase supply for whole-house instantaneous electric — for most households, storage is the practical path.
Sizing guide for Perth homes
| Household | Storage size (standard tariff) | Storage size (off-peak) |
|---|---|---|
| 1 person | 50–80L | 125L |
| 1–2 people | 125L | 160L |
| 2–3 people | 160L | 250L |
| Family of 4+ | 250–315L | 315–400L |
Off-peak systems only heat overnight, so they're sized larger to carry you through the day.
Cut the running cost: off-peak tariffs
On a flat tariff, electric storage is the most expensive hot water to run. On an off-peak tariff, the system heats overnight at a much cheaper rate — cutting running costs significantly. It requires the right metering setup and a correctly sized tank, which we confirm before recommending it.
Replace like-for-like, or upgrade?
If the budget is tight, a like-for-like electric swap is the fastest, cheapest fix — typically $1,000–$1,800 installed. But if you'll be in the home a while, a heat pump uses up to 70% less electricity and — with WA rebates — often pays back the price gap within a few years. We'll quote both so you can decide with real numbers. And if your home does have gas, compare with gas continuous flow.
Brands we install and repair
Rheem, Dux, Vulcan, Aquamax and more. Element and thermostat repairs on all major brands, usually in one visit.
Frequently asked questions
What size electric system do I need?
Rough guide: 50–80L for 1 person, 125L for 1–2, 160L for 2–3, 250–315L for a family of 4+. Go larger on off-peak.
Are electric systems expensive to run?
On a flat tariff, yes — the priciest type to run. Off-peak tariffs and correct sizing cut the cost significantly.
Replace like-for-like or upgrade?
Like-for-like is cheapest upfront. A heat pump costs more initially but uses up to 70% less electricity and attracts WA rebates — often paying back the gap in a few years.