Energy playbook · 9 tactics

9 Changes That Actually Cut an Energy Bill

Three systems dominate the bill. Everything else is rounding.

Fix the schedule before buying anything

Heating and cooling dominate most bills. A correct thermostat schedule costs nothing and outperforms every gadget sold to reduce consumption.

Shift load off peak if you are on time-of-use

Running laundry and dishwashers outside peak windows lowers the bill without reducing consumption at all.

Lower the water heater a few degrees

Water heating is usually the second largest load. A modest reduction plus insulating the first metres of pipe produces measurable savings.

Measure before you spend

A cheap plug meter for one week tells you more about your own house than any general advice, including this list.

Service the system you already have

A dirty filter or low refrigerant can cost more than the efficiency difference between two units you are comparing.

Compare the effective rate, not the plan name

Divide the total bill by kilowatt-hours used. Standing charges and levies mean the advertised rate is rarely what you actually pay.

Check self-consumption before sizing solar

Exported power earns a fraction of the retail rate. A daytime-empty house exports most of what it generates, which lengthens payback considerably.

Apply the repair-times-age test on HVAC

Multiply the quoted repair by the system age. Above roughly five thousand, replacement is usually the better use of the money.

Fix the envelope before upgrading the equipment

Sealing and insulating reduces the load, which means the replacement unit can be smaller and cheaper as well as more effective.

Put it to work

Calculators for these tactics

Energy & Utilities

Electricity Cost Calculator

What your usage costs monthly and annually, including standing charges and tiers.

Energy & Utilities

Solar Savings Calculator

Payback period and lifetime saving from a rooftop system after incentives.

Home & Property

HVAC Replacement Cost & Payback Calculator

Repair or replace, and how long a higher-efficiency unit takes to pay for itself.

Estimates, not advice. Every figure here is produced from the inputs you enter and the formula printed on the page. Rules differ by state, carrier, lender and contract, so use these numbers to prepare for a conversation with a qualified professional rather than to replace one. See our full disclaimer.