Understanding the Comparison
Geothermal and propane systems can both heat a home well. Yet their cost patterns are very different. Propane relies on delivered fuel. Geothermal relies on electricity and ground heat. This calculator compares both paths with common ownership inputs.
Important Inputs
The annual heating load is the starting point. It represents the useful heat your home needs. A larger home, colder climate, or weak insulation raises that load. The geothermal side uses coefficient of performance. A higher value means more heat from each unit of electricity. The propane side uses furnace efficiency. A higher value means less fuel is wasted.
Upfront cost matters too. Geothermal often costs more at installation. Ground loops, drilling, or trenching can add expense. Incentives can reduce that first cost. Propane equipment often costs less at the start. However, fuel cost can change the long term result.
Reading the Results
This tool estimates annual energy use, yearly operating cost, emissions, and payback. It also applies maintenance, cooling credit, fuel escalation, electricity escalation, and discount rate. These options help create a fuller ownership view. You can test optimistic, normal, and conservative cases.
Simple payback shows when extra geothermal cost may be recovered. Present value savings show a broader financial result. A positive value means geothermal is estimated to save money over the selected period. A negative value means propane remains cheaper under your assumptions.
Planning Tips
Use realistic local prices. Electric rates and propane delivery prices vary widely. Heating loads also vary by climate and building quality. Ask contractors for firm installation estimates. Review utility bills. The calculator is not a replacement for a professional audit. It is a planning aid for early comparisons.
For best results, run several scenarios. Try current prices first. Then raise propane escalation. Try a lower geothermal performance value. Test a higher repair allowance. These checks show how sensitive the choice is. The best system is not always the cheapest one. Comfort, reliability, space, emissions, and service access matter. A clear comparison helps you discuss bids with confidence. The example table gives sample assumptions. Replace those values with local quotes. Seasonal service, fuel delivery fees, panel upgrades, and loop design can change the answer. Keep notes when comparing contractor proposals.