Heat Pump vs Furnace in Indiana: Honest Math

The heat pump pitch sounds great on paper: move heat instead of generating it, get two or three units of heat for every unit of electricity, save money versus gas. Contractors selling heat pumps lead with that number. What they don't lead with is the balance point problem — and in Lebanon, Indiana, with 5,400 heating degree days per year and 23 days below 25°F, the balance point is where the math falls apart.

This is the honest version of the heat pump vs. furnace comparison for Boone County. No manufacturer talking points. Just the actual numbers.

How a Heat Pump Works

A heat pump is a refrigerant-cycle system that runs in reverse compared to your AC. In cooling mode, it moves heat from inside your house to outside. In heating mode, it extracts heat from outdoor air and moves it inside. Even cold air contains heat energy — down to about -13°F, though efficiency drops steeply as temperatures fall.

The key metric is COP: Coefficient of Performance. A COP of 3.0 means the heat pump delivers 3 units of thermal energy for every 1 unit of electrical energy consumed. Compare that to a gas furnace at 96% AFUE, which delivers 0.96 units of heat energy for every 1 unit of gas energy in. When the COP is above 1, the heat pump beats resistance heat. When COP is above 3, it's hard for gas to compete at current energy prices.

The COP Problem: Indiana's Balance Point

COP isn't constant. It drops as outdoor temperature drops, because there's less heat energy in colder air to extract. At 47°F outdoor temperature, a standard heat pump might have a COP of 3.5. At 17°F, that same unit might be at 1.5. Below a certain outdoor temperature — called the balance point — the heat pump can no longer keep up with the heating load, and backup heat (either electric resistance strips or a gas furnace) has to carry the load.

For Lebanon, IN, the NWS climate data puts the balance point for a standard heat pump at roughly 28°F–32°F. Below that, you're running on backup heat. A cold-climate heat pump (Mitsubishi Hyper-Heat, Carrier Greenspeed, Bosch IDS) pushes that balance point down to around 5°F–15°F — a meaningful improvement, but at significantly higher equipment cost.

Lebanon's Heating Degree Days: The Long Season Problem

Lebanon, IN averages approximately 5,400 heating degree days (HDD) per year. HDD is a measure of how much heating a building needs — one HDD for every degree-day the average temperature is below 65°F. For context, Atlanta is around 2,900 HDD. Minneapolis is around 8,200 HDD. Lebanon sits solidly in the middle of the heating belt.

With 23 days per year averaging below 25°F, and the balance point of a standard heat pump around 28°F–32°F, you have a meaningful chunk of your heating season where a standard heat pump is either struggling or running on backup heat. The shoulder seasons (October, November, March, April) are where heat pumps shine in Indiana — not January and February.

The Honest Math: Three System Scenarios

Option 1: Straight Electric Heat Pump (No Gas Backup)

For a typical 1,800 sq ft Lebanon home, a standard heat pump with electric resistance backup strips will likely see heating costs 15–25% higher than a high-efficiency gas furnace during a normal Indiana winter. The shoulder-season savings don't compensate for running resistance strips during the cold snaps. The math gets worse in a bad winter (2023–24 was rough). Indiana's electricity rate of roughly 13–15 cents/kWh versus gas at current prices makes this a tough case to build.

Option 2: Gas Furnace Only

A 96% AFUE two-stage gas furnace is the most cost-effective heating-only option for Boone County at current energy prices. Lower equipment cost, known performance in extreme cold, no balance point concern. The downside: no cooling-mode efficiency benefit, and if gas prices spike significantly relative to electricity, the economics shift.

Option 3: Dual-Fuel (Heat Pump + Gas Furnace Backup)

This is the configuration that actually makes sense for most Indiana homes. The heat pump handles heating down to the configured lockout temperature (typically set at 30°F–35°F for standard units, lower for cold-climate units). Below that, the gas furnace takes over. You get heat pump efficiency during the shoulder seasons — which represent the bulk of your heating hours — and reliable, cost-effective gas heat during the coldest stretches.

The tradeoff is equipment cost: you're maintaining two heating systems. But on a full system replacement, a dual-fuel setup often qualifies for the federal 25C tax credit (up to $2,000 for the heat pump portion) plus Duke Energy or Boone REMC rebates, which can close a significant portion of the cost gap.

When a Straight Heat Pump Makes Sense in Indiana

There are legitimate cases for a straight heat pump in Boone County:

• All-electric homes with no gas service: Running a new gas line costs $1,500–$4,000+. A cold-climate heat pump with properly sized backup strips may pencil out better than adding gas infrastructure.
• Well-insulated newer construction: A tight, well-insulated house has a lower heating load. The balance point matters less when the load at 20°F is small enough that backup strips run infrequently.
• Cold-climate units specifically: A Mitsubishi Hyper-Heat or Bosch IDS rated for full capacity to 5°F is a different product than a standard heat pump. The balance point analysis changes significantly.
• Homes prioritizing carbon footprint: If decarbonization is the goal and you're on a utility that's adding renewable capacity, the carbon math on a heat pump + clean electricity is better than gas.

Indiana Energy Prices in 2026: Which Side Is Winning?

As of early 2026, Indiana residential electricity averages roughly 13–15 cents/kWh. Natural gas for residential customers in the Duke Energy Indiana territory runs approximately $1.10–$1.30 per therm depending on season. At these rates, gas heat in a 96% AFUE furnace costs roughly $12–$14 per million BTU delivered. Electric resistance heat at 14 cents/kWh costs around $41 per million BTU. A heat pump at COP 2.5 costs around $16–$19 per million BTU — competitive with gas in shoulder season, losing to gas in peak heating.

These numbers shift if electricity rates drop (unlikely near-term) or gas prices spike (possible). The dual-fuel setup hedges both directions.

Our Recommendation for Boone County

For most Lebanon, Zionsville, and Whitestown homes: dual-fuel. Heat pump for the shoulder seasons where it's efficient, gas furnace backup for the January cold snaps. Size the heat pump to handle the cooling load (which is the binding constraint for most Indiana homes anyway) and let the gas furnace handle the heavy heating lift.

For all-electric homes or new construction with good insulation: cold-climate heat pump with properly sized backup. Standard heat pumps with resistance strips are a hard sell in this climate at current electricity rates.

If you want to run the actual numbers for your house — your square footage, your current utility rates, your insulation level — call us at (765) 894-0047. We'll do the math before recommending equipment, not after.