Independent energy calculators No signup Editable assumptions Formula shown
Topic guide

Home Heating & Cooling Costs

Heating and cooling decisions cannot be reduced to nameplate watts. A useful comparison starts with the home's current annual energy use, converts each option to useful heating or cooling delivered, and then adds climate, seasonal performance, installation cost, and the building envelope.

Decision path

Work through the numbers in this order

A calculator is useful only when its inputs describe the same real-world scenario.

  1. 01

    Build a current-cost baseline

    Start with a full year of fuel and electricity use when available. Separate heating, cooling, water heating, and fixed service charges. A nameplate wattage multiplied by every hour of the season is usually not a realistic HVAC baseline.

  2. 02

    Compare delivered heat, not input units

    Electricity, gas, oil, and heat pumps use different input units and efficiencies. Compare the cost of useful heat delivered to the home. For heat pumps, use seasonal efficiency or a range of COP values rather than one rated condition for the entire winter.

  3. 03

    Check the building before the equipment

    Air leakage, insulation, ducts, controls, climate, and thermostat schedules can change comfort and energy use. Reducing the load may allow smaller equipment and can be more valuable than comparing two oversized systems.

  4. 04

    Add installation and backup costs

    A running-cost advantage is not the same as a financial payback. Include equipment, electrical or duct work, maintenance, incentives, financing, and any backup or auxiliary heat expected at cold design conditions.

Calculators

Sensitivity check

Inputs that can change the answer

Test a realistic range for these variables instead of relying on one best-case result.

Current annual use
Bills provide a stronger baseline than equipment capacity or one month.
Seasonal efficiency
Actual performance changes with outdoor temperature, cycling, distribution, and controls.
Local energy prices
Compare the applicable electricity and fuel rates while keeping fixed charges separate.
Climate and design load
Sizing and low-temperature performance affect comfort, auxiliary heat, and cost.
Envelope and ducts
Air sealing, insulation, duct leakage, and airflow can change the result before equipment is replaced.

Guides

Primary guidance used for this topic

Sources checked August 12, 2026. Rates, incentives, equipment, and local requirements can change.