Electric vs Gas vs Solar Hot Water: Which Is Best in WA?
For most WA households, the best hot water choice comes down to running cost versus upfront cost. Electric storage is cheapest to buy but dearest to run; gas is a solid middle ground, especially continuous-flow; and solar or heat pump systems cost the most up front but are the cheapest to run and attract STC rebates. The right pick depends on your household size, roof, energy connection and budget. Here's how they compare.
Quick comparison table
| Type | Typical upfront (AUD, indicative) | Running cost | Lifespan | Best for |
|---|---|---|---|---|
| Electric storage | $1,200–$2,000 | High (higher on peak tariff) | 8–12 years | Low upfront budget; small homes; no gas connection |
| Gas storage | $1,400–$2,500 | Medium | 8–12 years | Homes with mains gas wanting steady supply |
| Gas continuous flow | $1,500–$3,000 | Medium (only heats on demand) | 12–20 years | Endless hot water; space-saving; varied demand |
| Solar (roof panels + tank) | $3,000–$6,000+ | Very low | 10–15 years (tank) | Sunny roof; long-term savings; larger households |
| Heat pump | $2,500–$5,000+ | Very low | 10–15 years | Efficiency without roof panels; STC rebate |
Figures are typical and indicative only, not a quote. Installation complexity, brand and rebates all shift the final price — always get a written quote.
Electric hot water
Electric storage systems are the cheapest to buy and simplest to install, which makes them popular for smaller homes and tight budgets. The trade-off is running cost: heating water with electricity is generally the most expensive way to do it, especially on a standard tariff. If you have a controlled-load or off-peak tariff and solar panels, the sums improve. Explore options with our electric hot water service.
Best for
Households with no gas connection, small homes, rentals, or anyone prioritising a low upfront cost over long-term running savings.
Gas hot water
Gas is the middle-ground choice and a popular one in Perth, where natural gas (via ATCO) is widely available. It heats water quickly and costs less to run than electric. You've got two main types:
- Gas storage keeps a tank of hot water ready to go — reliable, but you can run out during heavy use.
- Gas continuous flow (instantaneous) heats water only as you need it, so you never run out and there's no standby heat loss. It's compact and typically lasts longer, too.
All gas work must be done by a licensed gas fitter. See our gas hot water service for installation and repairs.
Best for
Homes with mains gas that want a good balance of upfront cost, running cost and reliable performance — continuous flow especially for busy households.
Solar and heat pump hot water
These are the cheapest systems to run and the kindest on your bills long-term, though they cost more to buy. Perth's climate is well suited to solar hot water, and both solar and heat pump units qualify for federal STC rebates.
- Solar hot water uses roof-mounted panels to heat water, with an electric or gas booster for cloudy days. Best where you have a suitable, sunny roof.
- Heat pump works like a reverse-cycle air conditioner, pulling warmth from the air to heat water using a fraction of the electricity of a standard element. No roof panels needed, which makes it a great option where solar isn't practical.
The STC rebate can knock a meaningful chunk off the upfront price — often around $1,500 or more on a heat pump — which narrows the gap with cheaper systems. Learn more in our guide to solar hot water rebates in WA, and see our solar and heat pump hot water service.
One point worth understanding: the running-cost savings from solar and heat pump systems are real but they take time to pay back the higher purchase price. If you're staying in your home for the long haul, that payback is well worth having. If you might move in a couple of years, a cheaper system can make more sense — though efficient hot water can also be a selling point for buyers.
Best for
Households planning to stay put for years, wanting the lowest running costs and smallest energy footprint, and happy to invest more up front to save later.
Don't forget sizing
Choosing the right type is only half the decision — the system also has to be the right size for your household. A unit that's too small means running out of hot water during back-to-back showers; one that's too big wastes money heating water you never use. As a rough guide, capacity is matched to the number of people and bathrooms in the home, and continuous-flow gas units are rated by flow rate rather than tank size. A licensed plumber will size it properly based on your actual usage, which is one more reason to get professional advice rather than picking a unit off a shelf.
How to choose
Run through these questions:
- Do you have mains gas? If yes, gas continuous flow is often the sweet spot. If not, electric or heat pump makes more sense.
- How long will you stay? Long-term owners get the most from solar and heat pump savings.
- What's your budget now vs later? Low upfront points to electric; low running cost points to solar or heat pump.
- How much hot water do you use? Bigger households benefit from continuous flow or a well-sized solar system.
- What's your roof like? A sunny, unshaded roof favours solar; otherwise a heat pump gets similar efficiency without panels.
Whichever you choose, the brand matters for reliability and warranty. Our guide to hot water brands in WA compares the main options like Rheem, Rinnai, Dux, Solahart, Bosch and Vulcan.
Get the right system for your home
There's no single "best" — only the best for your household, roof and budget. A licensed plumber can size the system correctly, handle the gas or electrical connection safely, and sort out any rebate paperwork.
Not sure which way to go? Call our licensed Canning Vale plumbers for honest advice and a written quote.
Frequently asked questions
Which hot water system is cheapest to run in WA?
Solar and heat pump systems are the cheapest to run. They use free energy from the sun or heat drawn from the air, so running costs are very low. They cost more up front, but STC rebates and years of savings usually make up the difference.
Is gas or electric hot water better in Perth?
If you have mains gas, gas is generally cheaper to run than electric and heats water fast — continuous flow especially. Electric costs less to buy but more to run. Without a gas connection, a heat pump often beats standard electric on running cost.
Do solar and heat pump hot water systems get a rebate?
Yes. Both qualify for the federal Small-scale Technology Certificate (STC) rebate, which is applied as an upfront discount — often around $1,500 or more on a heat pump. There's currently no separate WA state rebate, but the federal STC scheme applies statewide.
How long do these systems last?
Electric and gas storage units typically last 8–12 years, gas continuous flow around 12–20 years, and solar and heat pump systems roughly 10–15 years. Regular servicing and Perth's water conditions both affect the real-world lifespan.