Myth: leaving the heater or air conditioner on all day is cheaper
A stubborn belief is that a heater or air conditioner uses more energy starting up than it does running, so it is cheaper to leave it on all day than to switch it on and off. For the vast majority of modern systems this is false. The energy to reach a comfortable temperature is far smaller than the energy spent maintaining it for hours in an empty or poorly sealed house.
Heating or cooling only when and where you need it is almost always cheaper. The one nuance is solar: if you have panels, pre-cooling or pre-heating with your own midday generation, then coasting, can make sense — but that is about using free solar, not about the system being cheaper to leave running.
Myth: appliances on standby cost nothing
Devices left in standby — TVs, set-top boxes, game consoles, microwaves, chargers and modems — draw a small trickle of power around the clock. For any single device it is tiny, which is where the myth comes from. But across a whole house, standby "vampire" loads add up to a small but real slice of the annual bill, running 24 hours a day, every day.
Switching off the worst offenders at the wall, or using a smart plug, does save money — modestly. The caveat is proportion: chasing standby loads while ignoring a poorly matched energy plan or an inefficient heater is straining at the small stuff. Fix the big loads first, then trim the vampires.
Myths about how power is priced
- Myth: solar means my bill should be near zero
- Only if you use your generation. With feed-in rates now low, exported solar earns little — the savings come from self-consuming power during the day, plus you still pay the daily supply charge regardless.
- Myth: the plan with the lowest c/kWh is cheapest
- Not necessarily. A low usage rate paired with a high daily supply charge can cost more overall. The cheapest plan depends on your total usage and the mix of charges, not one headline number.
- Myth: turning lights off is where the real savings are
- Lighting, especially LED, is a small part of most bills. Heating, cooling, hot water and any EV charging dwarf it — that is where meaningful savings live.
- Myth: my retailer keeps me on their best deal
- Retailers rarely move you onto a cheaper plan automatically, and benefit periods lapse quietly. Staying put after a discount ends often means paying more, which is why comparing periodically matters.
What actually moves the needle
The habits that genuinely cut bills are unglamorous: heat and cool efficiently and only where needed, seal draughts, run big flexible loads in off-peak or solar hours, and put hot water on a cheap controlled-load tariff. These target the loads that dominate the bill, rather than the rounding errors.
The biggest overlooked saving, though, is the rate itself. Many households are on a plan whose discount has lapsed or which never suited their usage. EnergySorted costs 16,000+ plans against your real bill — no retailer commission, around $39 a year — and its Bill Health Score tells you at a glance whether you are overpaying. No amount of switching off lights beats being on the wrong plan by hundreds of dollars a year.