Heat Pump Vs Gas Boiler
Calculator
Results
- Break-even (years)
- 12.500448 yr
- Net position at the horizon
- $3,789.62
- Total savings
- $8,289.62
- First-year saving
- $290.61
- Electricity used per year (kWh)
- 3,333.333333 kwh
- Gas used per year (kWh)
- 13,636.363636 kwh
Cumulative cash flow crossing zero at break-even
- Cumulative cash flow
- Cumulative cost of doing nothing
- Cumulative cost with the upgrade
Year-by-year cash flow until break-even
| 1 | 290.61 | 290.61 | -4,209.39 | 1,337.27 | 5,546.67 |
| 2 | 301.42 | 592.03 | -3,907.97 | 2,711.36 | 6,619.33 |
| 3 | 312.57 | 904.60 | -3,595.40 | 4,123.38 | 7,718.78 |
| 4 | 324.04 | 1,228.64 | -3,271.36 | 5,574.45 | 8,845.81 |
| 5 | 335.87 | 1,564.51 | -2,935.49 | 7,065.76 | 10,001.25 |
| 6 | 348.04 | 1,912.55 | -2,587.45 | 8,598.50 | 11,185.96 |
| 7 | 360.58 | 2,273.13 | -2,226.87 | 10,173.93 | 12,400.80 |
| 8 | 373.50 | 2,646.63 | -1,853.37 | 11,793.32 | 13,646.69 |
| 9 | 386.80 | 3,033.44 | -1,466.56 | 13,457.99 | 14,924.56 |
| 10 | 400.51 | 3,433.94 | -1,066.06 | 15,169.31 | 16,235.36 |
| 11 | 414.62 | 3,848.57 | -651.43 | 16,928.66 | 17,580.09 |
| 12 | 429.16 | 4,277.73 | -222.27 | 18,737.49 | 18,959.76 |
| 13 | 444.14 | 4,721.87 | 221.87 | 20,597.29 | 20,375.42 |
| 14 | 459.56 | 5,181.43 | 681.43 | 22,509.58 | 21,828.15 |
| 15 | 475.45 | 5,656.88 | 1,156.88 | 24,475.94 | 23,319.06 |
| 16 | 491.81 | 6,148.69 | 1,648.69 | 26,497.99 | 24,849.30 |
| 17 | 508.67 | 6,657.36 | 2,157.36 | 28,577.40 | 26,420.04 |
| 18 | 526.03 | 7,183.39 | 2,683.39 | 30,715.90 | 28,032.51 |
| 19 | 543.91 | 7,727.29 | 3,227.29 | 32,915.25 | 29,687.95 |
| 20 | 562.32 | 8,289.62 | 3,789.62 | 35,177.28 | 31,387.66 |
Comparison
| Scenario | Total cost over the horizon | Cumulative energy cost | Net position at the horizon |
|---|---|---|---|
| Do nothing | 35,177.28 | 35,177.28 | 0.00 |
| With the upgrade | 31,387.66 | 31,387.66 | 3,789.62 |
Formula
saving(n) = (Q/η_boiler × p_gas − Q/COP × p_elec) × (1+g)^(n−1) + Δservice= 12.50
Note
This is a simplified cash-flow model. It projects the prices, escalation rate and equipment costs you entered with a single geometric escalation and no discounting, no inflation adjustment, no financing costs and no tax treatment; savings are assumed to accrue evenly within each year, which is what the fractional break-even interpolates. Real energy prices, tariff structures, grants, weather, occupancy and equipment performance vary widely and change over time. A break-even of zero means the cumulative cash flow never crosses into positive territory within the horizon you chose. Get a professional energy assessment and a written quotation before committing to any of these measures.
More in Energy payback
See all →Frequently asked questions
What does this calculator compare exactly?+
It compares the total cost of installing and running a heat pump against a gas boiler over a chosen period, factoring in equipment cost, installation, and ongoing fuel or electricity costs.
Why can a heat pump cost more upfront but less over time?+
Heat pumps typically have higher installation costs but move heat rather than generate it by burning fuel, so they use less energy per unit of heat delivered, which usually lowers running costs over the years.
Does the comparison account for climate differences?+
Heat pump efficiency drops in very cold climates unless it's a cold-climate model, so the running-cost estimate is only as accurate as the efficiency figure you enter — check your specific heat pump's rated performance for your climate.
How do local energy prices change the outcome?+
Where electricity is expensive relative to gas, a heat pump's efficiency advantage may not fully offset the higher electricity cost per unit of heat, so the crossover point depends heavily on your local utility rates.
Are incentives or rebates included in the calculation?+
The calculator uses the net installed cost you enter, so include any rebates or tax credits in that figure to get an accurate comparison — many regions offer significant incentives specifically for heat pump installations.