How Much Does
Hot Water Cost To Run?

Why Hot Water Is One Of The Biggest Household Energy Costs

Heating water requires a massive amount of energy. In the average Australian home, water heating accounts for roughly 25% to 30% of total household energy consumption. Every time someone takes a shower, runs the dishwasher, or uses the washing machine on a warm cycle, the hot water system must work to recover the temperature.

During colder months, the incoming mains water is colder, meaning the system has to work even harder to reach the target temperature. This is why many families notice a significant spike in their energy bills during winter.

What Determines Hot Water Running Costs?

• Household Size: More people means more showers, more washing, and higher hot water demand.
• Water Usage Habits: Long showers and frequent use of hot water for laundry significantly increase costs.
• Energy Tariffs: The cost of electricity or gas per unit (kWh or MJ) dictates the baseline running cost. Off-peak tariffs can help lower costs for electric systems.
• System Efficiency: Modern heat pumps and solar systems use far less energy to produce the same amount of hot water compared to older technologies.
• Climate: Warmer climates like the Gold Coast require less energy to heat incoming mains water.
• System Maintenance: A well-maintained system operates more efficiently. Sediment build-up or failing components can cause a system to consume more energy.

Electric Hot Water Running Costs

Standard electric storage systems are the most expensive to run. They use direct resistance heating, meaning they consume 1 unit of electricity to produce roughly 1 unit of heat. To manage costs, many homeowners connect these systems to an off-peak tariff, allowing them to heat water overnight when electricity rates are lower.

However, even on off-peak rates, the sheer volume of electricity required makes them costly over the long term.

Gas Hot Water Running Costs

Gas hot water systems, particularly continuous flow models, only heat water as it is needed, which eliminates the standby heat loss associated with storage tanks. While gas was historically cheaper than electricity, rising gas prices have made these systems more expensive to run in recent years.

Gas storage systems are generally the least efficient gas option due to heat loss from the tank and the constant pilot light or burner operation.

Heat Pump Running Costs

Heat pumps offer some of the lowest running costs available.

Instead of generating heat directly, heat pumps extract ambient heat from the air and transfer it to the water. This process is incredibly efficient. A quality heat pump can produce 3 to 4 units of heat for every 1 unit of electricity it consumes (a COP rating of 3.0 to 4.0).

This means a heat pump can reduce your hot water electricity consumption by up to 70% compared to a standard electric system. In the warm Gold Coast climate, heat pumps operate at peak efficiency almost year-round.

Solar Hot Water Running Costs

Solar hot water systems can virtually eliminate your hot water bills.

By using free energy from the sun to heat water, solar systems have the lowest baseline running costs. The only energy consumed is by the circulation pump (if it's a split system) and the booster element.

The booster is only required on cloudy days or when household demand exceeds the solar heated supply. With the Gold Coast's abundant sunshine, a well-sized solar hot water system will rely very little on its booster.

How Household Size Affects Running Costs

How Solar Power Can Reduce Hot Water Costs

If you have rooftop solar panels (PV), you can use them to drastically reduce your hot water costs. By putting your electric hot water system or heat pump on a timer to run during the middle of the day, the system will heat your water using the free electricity generated by your panels.

Pairing a highly efficient heat pump with a solar PV system is one of the most effective ways to achieve near-zero hot water running costs.

Common Reasons Hot Water Bills Increase

• Failing Thermostats: A faulty thermostat might cause the system to constantly heat water, wasting massive amounts of energy.
• Faulty Elements: If an element is failing, the system has to work harder and longer to reach the target temperature.
• Leaks: A leaking PTR valve or pipe means you are constantly losing heated water and replacing it with cold water that needs heating.
• Ageing Systems: As systems age, sediment build-up reduces their efficiency.
• Incorrect Settings: Setting the thermostat too high wastes energy.

How To Reduce Your Hot Water Costs

• Fix Leaks Immediately: Don't ignore a dripping overflow pipe or leaking tap.
• Install Water-Efficient Showerheads: Reducing the flow rate means you use less hot water per shower.
• Wash Clothes in Cold Water: Modern detergents are designed to work perfectly in cold water.
• Check Your Tariffs: Ensure your electric system is on an off-peak tariff if applicable.
• Upgrade Your System: The most impactful change is replacing an old, inefficient electric or gas system with a modern heat pump.

Real-World Examples

How Todd's Helps Homeowners Reduce Hot Water Costs

We don't just sell hot water systems; we provide solutions. We assess your household's hot water usage, review your energy setup, and evaluate your existing infrastructure. Based on this, we recommend the system that will provide the best balance of upfront affordability and long-term running cost savings.

Why Gold Coast Homeowners Choose Todd's

As a family-owned local business with over 23 years of experience, we pride ourselves on honest, expert advice. Our team includes licensed plumbers, electricians, and solar accredited technicians, meaning we have the expertise to install and maintain the most energy-efficient systems available.