Rockhampton's hot weather means you have got some good options for hot water. Cold water inlet temperatures are higher than down south, so almost any system runs more efficiently here. The right choice depends on your setup and how long you plan to be in the place.
Electric storage
The cheapest install option, around $1,400 to $2,000 fitted. Reliable and easy to replace. The downside is running cost. A family of four on grid electric pays $700 to $900 a year. If you have got solar panels, you can run the heating element during the day for almost nothing.
Gas (natural or LPG)
Most Rocky homes are on LPG bottles rather than natural gas. Bottle gas is fine but the per-megajoule cost is higher than mains gas. Install around $1,800 to $2,400. Annual running cost around $600 to $800 for a family. Hot water on demand without a tank if you go for continuous flow gas.
Solar hot water
Excellent option for Rockhampton given the sunshine hours. Roof-mounted panels with a storage tank either on the roof or at ground level. Install $3,500 to $5,000 fitted. Running cost drops to near zero most months. Most systems include a small electric or gas booster for cloudy stretches. Payback period around 4 to 7 years.
Heat pump
The standout pick for most Rocky homes built in the last 15 years. Uses about a third of the electricity of a standard tank because it pulls heat from the air. Combined with solar panels, running cost is near zero. Install around $3,200 to $4,500 after federal STC rebates. Compressor unit makes a low hum so install location matters.
What we usually recommend
If you have solar panels: heat pump. Combination of low install (with rebates) and very low running cost.
If you do not have solar but you have got a north-facing roof: proper solar hot water system. Best long-term value in Rocky's climate.
If you are renting it out: electric storage replacement. Lowest install cost. Reliable. Easy for the next owner or tenant.
The salt-air factor
If you are in Yeppoon or anywhere close to the coast, choose a stainless steel tank rather than a painted steel one. Painted tanks rust through within 8 to 10 years in coastal conditions. Stainless lasts 15 to 20 years. Worth the extra $300 to $500 upfront.