Gas, Electric or Heat Pump Hot Water
How gas, electric storage and heat pump hot water really compare on running costs, suitability and lifespan, explained in principles not sales talk.
By the Brighton Plumbing Co teamPublished 12 July 2026
The three families, in one paragraph each
Gas systems burn natural gas to heat water, either storing it in a tank or heating it on demand through a continuous-flow unit on the wall. They heat water fast, recover quickly after heavy use, and continuous-flow models never run out, but they depend on a gas connection and a flue, and gas as a fuel is becoming a more deliberate choice in Victoria than it used to be.
Electric storage systems are the simplest of the lot: an insulated tank with one or two heating elements, essentially a large kettle. They are cheap to buy, easy to install almost anywhere including indoors, and have the fewest parts to fail. Their weakness is running cost, because they turn one unit of electricity into at most one unit of heat, though a tank heated overnight on a cheaper tariff or during the day from solar changes that picture considerably.
Heat pumps are electric systems that work like a refrigerator in reverse: they extract heat from the surrounding air and move it into the water. Moving heat is far more efficient than generating it, so a heat pump delivers several units of heat per unit of electricity. That efficiency is why they attract government incentives. The trade-offs are a higher purchase price, a compressor that makes some noise, slower recovery than gas, and a preference for airflow, which usually means an outdoor or well-ventilated installation.
Running costs, in principles rather than dollars
We deliberately avoid quoting running-cost figures, because they shift with every tariff change and depend heavily on your household. The principles, though, are stable.
- Efficiency ranks: heat pump first by a wide margin, gas second, conventional electric storage last. A heat pump moves heat rather than making it, so the same shower costs a fraction of the energy.
- Tariffs and timing can reorder the middle. Electric storage or a heat pump running on off-peak rates, or on your own rooftop solar in the middle of the day, competes very differently than the same unit on a flat peak tariff.
- Gas carries a fixed supply charge. If hot water is the last gas appliance in the house, the daily connection cost belongs in the comparison, and dropping the connection entirely is part of why many households electrify.
- Household pattern matters. A big family emptying a tank nightly rewards fast recovery or continuous flow. A one or two person household wastes money keeping a large tank hot around the clock.
- Purchase price and running cost pull in opposite directions. The least expensive unit to buy is generally the dearest to run. It is a genuine trade-off, and the right answer depends on how long you will own the home.
Suitability: what your house gets a vote on
Around Brighton and Bayside, the house often narrows the choice before preferences do. No gas connection, or a plan to disconnect it, rules out gas. A compact Gardenvale unit or Elwood apartment may have nowhere suitable for an outdoor compressor, which complicates a heat pump, while an internal cupboard suits electric storage nicely. Heritage streetscapes can limit where flues and wall units can visibly go on a period frontage.
Close to the bay, siting and corrosion enter the picture for anything installed outside. Salt air shortens the life of casings, valves and especially heat pump evaporator coils, so coastal homes should weight indoor-friendly options, sheltered locations and models built for coastal installation. We cover that side fully in our guide to choosing a hot water system for a coastal home.
Noise deserves an honest mention too. A heat pump compressor is comparable to a quiet outdoor air conditioning unit. That is fine along most driveways, but positioned under a neighbour’s bedroom window on a narrow Bayside block it becomes a relationship problem, and residential noise rules apply. Placement solves this, but it has to be thought about before installation day.
Lifespan and maintenance, briefly and honestly
No system is fit-and-forget. Storage tanks, gas or electric, rely on a sacrificial anode that must be checked and eventually replaced if the tank is to reach old age, and relief valves on any tank need periodic testing. Continuous-flow gas units avoid tank corrosion entirely but appreciate an occasional service of burners and filters. Heat pumps add a compressor and fan to the usual tank maintenance, and near the coast their coils should be specified and cared for accordingly.
As a general shape: simple electric tanks and continuous-flow gas units are the long-service veterans when maintained, storage gas sits in the middle, and heat pumps are newer technology with fewer thirty-year-old examples around, offset by solid warranties from the established makers. Whatever you buy, the maintenance habit matters more than the badge.
How we would decide at your kitchen table
If a household asks us for the short version, it goes like this. If you plan to stay put for years and can site it well, a heat pump is usually the strongest long-term choice, helped along by the incentive schemes running in Victoria; check the current federal and state programs, or ask us, since eligibility and amounts change. If you have gas, love never running out of hot water and have a big household, continuous-flow gas remains a genuinely good system. If budget is tight, the install spot is indoors, or the property is a rental where simplicity wins, electric storage still earns its place, especially with solar or off-peak power behind it.
Replacing a hot water system in Victoria is licensed work, and gas-fitting and the associated compliance certificates make that non-negotiable for gas units in particular. If your current system is limping, have the repair-versus-replace conversation before it fails completely. A choice made calmly beats one made during a cold shower, and we are happy to talk through the options for any home in Brighton, Brighton East, Hampton, Gardenvale, Elwood or Sandringham.
Common questions
Do heat pumps work in Melbourne winters?
Yes. Modern heat pumps are designed to extract heat from cold air and operate reliably in Melbourne conditions, and most include a booster element for the coldest snaps. Efficiency dips a little as the air gets colder, but they remain far more efficient than a standard electric element year-round.
Should I replace my gas hot water with the same thing?
Like-for-like is the fastest path, and sometimes the right one, but a failed unit is also the natural moment to reconsider. If you are thinking about disconnecting gas, adding solar, or you qualify for heat pump incentives, it is worth an honest conversation before defaulting to the same badge on the same wall.
What size system does my household need?
It depends on how many people shower, when, and whether demand peaks together in the morning. Tanks are sized by usable hot water per heating cycle, continuous-flow units by flow rate at temperature. We size systems from your actual usage pattern rather than a rule of thumb, because oversizing wastes money every day and undersizing means cold showers.