Energy Cost Comparison Calculator

Convert all fuels to cost per useful BTU delivered. Account for equipment efficiency (e.g., 95% for gas furnace, 300% for heat pump, 100% for electric resistance). The calculator handles these conversions: for example, natural gas at $1.50/therm with 95% efficiency costs $1.58 per 100,000 useful BTU.

AFUE (Annual Fuel Utilization Efficiency) shows what percentage of fuel energy becomes useful heat. A 95% AFUE furnace delivers 95,000 BTU of heat per 100,000 BTU of fuel burned. Higher AFUE means lower operating costs. Modern gas furnaces range from 80-98% AFUE.

Heat pumps move heat rather than generate it, measuring efficiency as COP (Coefficient of Performance) or HSPF. A COP of 3.0 means 300% efficiency - 3 BTU of heat moved per BTU of electricity used. In mild climates, heat pumps can be 2-4x cheaper than resistance heating.

Beyond fuel price: equipment efficiency, maintenance costs, equipment lifespan, installation costs, and energy price volatility. Electricity prices are more stable than gas/oil. The calculator includes lifecycle cost analysis considering equipment replacement and maintenance.

Electric heat pumps beat gas when electricity costs less than 3x the gas price per BTU. With a COP of 3.0, if gas costs $1/therm and electricity is under $0.10/kWh, heat pumps win. Also consider: no combustion safety risks, lower maintenance, and potential solar offset.

Calculate Total Cost of Ownership over the equipment lifespan (typically 15-20 years for HVAC). Include purchase price, installation, annual fuel costs, maintenance, and efficiency degradation. The calculator provides NPV analysis to compare options with different upfront costs.