This blog post was accurate at the time of publishing. However, programs, policies and rebates may have changed since then. We recommend checking our website or contacting us directly for the most current information on 1300 430 917.

If your electricity bill rises sharply in summer, it’s not just because it’s hot it’s because summer places the highest demand on household and business energy systems. According to the latest Australian Energy Regulator’s State of the Energy Market report, electricity demand across Australia now peaks most sharply during hot summer afternoons and evenings, largely due to residential cooling and appliance use.

Summer peak demand places significant pressure on the electricity network, which directly influences wholesale prices and ultimately flows through to customer bills. Understanding how and when electricity is used in summer helps explain why costs increase and what households can do to manage them.

How Much Electricity Do Australian Homes Use?
Across the National Electricity Market (NEM), residential customers consume around 60 terawatt hours (TWh) of electricity each year. About 40 TWh comes from the grid, while 20 TWh is supplied by rooftop solar, which now plays a major role in household energy use

On a day-to-day level, this averages out to roughly 16–25 kWh per household per day, depending on household size, climate and appliances. In summer, however, usage can rise well above average on hot days.

Why Summer Electricity Use Is Higher
The AER report highlights that electricity use hasn’t simply increased overall, it has shifted in timing.

• Midday grid demand has fallen as rooftop solar supplies more household energy during daylight hours
• Early morning and evening demand has increased, when solar output drops and households rely on the grid
• Summer heatwaves create sharp demand spikes, driven largely by cooling loads
This shift in timing is a key reason why summer electricity bills often feel disproportionately high, even if overall usage has not dramatically increased.

Which Appliances Use the Most Power in Summer?
While every home is different, the same few systems consistently account for the largest share of summer electricity use.

1. Air Conditioning (Largest Contributor)
Air conditioning is the single biggest driver of summer electricity demand. During extreme heat, cooling systems push grid demand to its annual peak.
Running a split-system air conditioner for several hours can add 8–15 kWh or more per day, depending on system size and efficiency.

2. Hot Water Systems
Hot water is one of the largest year-round energy users, but its impact becomes more noticeable in summer when it often operates during peak pricing periods.
Older electric hot water systems that heat water on demand or at night can quietly add 3–5 kWh per day, increasing evening electricity costs.

3. Pool Pumps and Outdoor Equipment
Pool pumps are a seasonal but significant load, typically using 2–4 kWh per day when running regularly. Combined with outdoor lighting and other summer-only equipment, this adds to daily consumption.

4. Fridges, Freezers and Everyday Appliances
Fridges and freezers run continuously and consume more power in summer as they work harder to maintain safe temperatures. Lighting, cooking, laundry and electronics add a further 2–4 kWh per day in most households.

A Typical Summer Day: What It Can Add Up To
On a hot summer day, household electricity use can look like this:

• Air conditioning: 8–15+ kWh
• Hot water: 3–5 kWh
• Pool pump (if applicable): 2–4 kWh
• Fridge & freezer: 1–2 kWh
• Lighting & appliances: 2–4 kWh

That means total daily usage can easily exceed 25–30 kWh, well above annual averages, especially
during heatwaves.

Why Summer Power Bills Feel So Expensive

It’s not just how much power you use – it’s when you use it.

The AER notes that wholesale electricity prices are highest during evening peak periods, when household demand is strong and solar generation has dropped. Many homes generate low-cost solar energy during the day, then purchase higher-priced grid electricity at night, creating a costly mismatch.

This timing issue is one of the biggest drivers of high summer power bills across Australia

What Your Summer Power Bill Is Really Telling You
Your summer bill is effectively a stress test for your home. It reveals:

• How heavily you rely on cooling
• Whether major appliances are energy efficient
• How exposed you are to peak-time pricing
• Whether your home energy setup works together or against itself

Government Rebates That Can Reduce Summer Energy Costs

Many Australian households are paying more than they need to because they are not aware of state-based energy efficiency schemes designed to lower upfront upgrade costs.

In South Australia, eligible households and businesses can access significant discounts through the Retailer Energy Productivity Scheme (REPS). REPS is a South Australian Government program that requires energy retailers to fund energy-saving upgrades, with the savings passed directly on to customers.

Through REPS, eligible customers may receive subsidised upgrades for:

• High-efficiency air conditioning
• Heat pump hot water systems
• Efficient refrigeration and appliances
• Other approved energy-saving technologies

These upgrades directly target the biggest contributors to summer electricity bills, helping reduce peak demand and long-term energy costs.

Other states offer similar programs under different names, including:

• Victorian Energy Upgrades (VEU)
• NSW Energy Savings Scheme (ESS)

Eligibility, rebate values and approved products vary by state and change over time, which is why professional advice is critical.

👉 MAC Trade Services works with accredited energy efficiency schemes and can help identify which rebates apply to your home or business, ensuring you access the maximum available savings.