How do the two systems produce heat?
Combi boiler produces heat by burning natural gas; a well-functioning condensing boiler gives about 8.5–9.5 kWh of usable heat from 1 m³ of natural gas. Heat pump on the other hand, does not produce heat; it takes it from the outdoor air and moves it to the water, and for every 1 kWh of electricity it uses it can deliver 3–5 kWh of heat in mild weather. This ratio is called COP, and the seasonal average is called SCOP.
Do your own calculation in 3 steps
- Cost of 1 kWh of heat with natural gas = natural gas price per m³ (taxes included) ÷ 9
- Cost of 1 kWh of heat with a heat pump = electricity price per kWh ÷ SCOP
- The smaller one is more economical. If you divide the electricity price by the cost of 1 kWh of heat from natural gas, you get the break-even SCOP ; if your unit's SCOP is above it, the heat pump wins.
On the electricity side, use the correct unit price for your home's tariff (single-rate, three-rate, tiered). To do the calculation per unit, you can use our energy and operating cost calculator.
How does the tiered natural gas tariff change the calculation?
Since April 2026, a province-based tiered tariff has applied to residential natural gas. Monthly consumption limits were set for each province according to climate and published on the BOTAŞ website; consumption below the limit is billed with a higher subsidy, while the portion above the limit is billed with a lower subsidy, at a price close to cost. Limits rise in the winter months; for example, for Ankara the highest limit is in January (BloombergHT).
This means: for a home that stays below the limit, natural gas is still cheap energy; but if a large, poorly insulated or crowded home exceeds the limit every winter, the part above the limit should be compared with the cost of a heat pump. Redo step 1 of the calculation using the price per m³ above the limit.
Which one in which situation?
| Situation | Usually the suitable solution |
|---|---|
| No natural gas, detached house or summer home | Air-to-water heat pump |
| New building, underfloor heating | Heat pump (a low water temperature increases efficiency) |
| Natural gas available, consumption usually below the limit | Combi boiler; an air conditioner can help on mild days |
| Natural gas available, limit constantly exceeded in winter | Hybrid: heat pump as the main source, combi boiler as cold-day backup |
| Apartment with old radiators | Check radiators and insulation first; often combi boiler + air conditioner |
| Building with solar panels | Heat pump, evaluated together with the panels' production |
Hybrid system: the best of both
In a hybrid setup, the heat pump is connected to the same system as the existing combi boiler. The control panel decides which one runs based on the outdoor temperature and energy prices: the heat pump on mild and cool days, the combi boiler in freezing cold. This reduces natural gas use above the limit and also avoids spending electricity during very cold hours when the heat pump is inefficient. For homes whose combi boiler is new, it is usually the most sensible way to transition.
Let's calculate it together with your bills
Send us last winter's natural gas and electricity consumption, the home's floor area and the heating system; we will compare a heat pump, combi boiler or hybrid.
Before deciding
Have your natural gas bills (m³) and electricity bills (kWh) from the last two winters ready. With these two sets of data we can see your home's real heat demand and how far it exceeds the limit. The right decision is often not 'one or the other' but using both at the right time. We explained the items that determine the price in our article on heat pump prices.
Frequently asked questions
Is a heat pump cheaper than natural gas?
Yes, if the heat pump's SCOP is higher than the ratio of the electricity and natural gas unit prices. Because natural gas above the limit is expensive under the tiered tariff, the advantage grows in high-consumption homes.
Should I remove my combi boiler and install a heat pump?
If your boiler is new, it usually does not need to be removed; using both together in a hybrid setup may be more economical.
Does a heat pump work efficiently with a radiator system?
Efficiency drops as water temperature rises. It works well if the radiators are sufficient at low temperatures; if not, larger radiators or a hybrid solution can be considered.
Where can I find out my tiered tariff limit?
Monthly limits by province are published on the BOTAŞ website; your bill also shows which tier your consumption falls into.