A heat pump moves heat from the outdoor air, ground or water into a room: electricity powers the compressor, while refrigerant helps transfer the energy. So the pump uses electricity but delivers more heat than a conventional electric heater could produce from the same amount of energy; actual consumption depends on operating conditions and the equipment itself.
That is the principle that sets a heat pump apart from a boiler or heater: it moves heat rather than generating it. Let’s look at how the process works and what determines how much electricity a heat pump uses in practice.
| Source | How heat is supplied | What to check |
|---|---|---|
| Air | From outdoor air | Operating conditions in the local climate |
| Ground | Through an external ground loop | Whether a loop can be installed |
| Water | From water | Source availability and connection design |
- 2,5–5 кВт тепла на 1 кВт электричества Stated heat output range for a heat pump
- 4–6 °C Approximate temperature drop in the glycol mixture as it extracts heat
- до 80% Upper estimate of potential heating-cost savings
How does a heat pump transfer heat into a home?
From the external loop to the heating system
A heat pump moves heat from the outdoor air, ground or water into the home’s heating system: the external loop draws energy from the surroundings, and the pump transfers it into the house. A non-freezing fluid circulates through the loop, carrying heat to the unit.
- Air: heat comes from the outdoor air.
- Ground: heat is extracted from the earth.
- Water: water serves as the heat source.
In the evaporator, energy passes from the non-freezing fluid to the working fluid. The pump then raises the temperature of the working fluid and transfers the resulting heat to the indoor heating circuit, which warms the rooms.
The principle is similar to how a refrigerator works, but the desired result is the opposite: a refrigerator removes heat from its compartment, while a heat pump directs it into the home. For every kilowatt of electricity used, the system delivers 2,5–5 kW of heat; the actual result depends on operating conditions.
How much heat does a heat pump deliver per kilowatt of electricity?
A heat pump delivers 2,5–5 kW of heat for every 1 kW of electricity consumed. This is a range, not a promise that every installation will deliver the same amount of heat under all conditions.
Electricity does not turn into several kilowatts of heat by itself: it powers the pump, which moves additional energy from the air, ground or water into the heating system. That is why the heat output can exceed the electricity used.
Where the difference comes from
A glycol mixture circulates through the external loop: it absorbs heat from the surroundings and transfers it to the pump. As heat is extracted, the temperature of this fluid may drop by approximately 4–6 °C; this change applies to the glycol mixture, not to the amount of electricity consumed.
The stated range of 2,5–5 kW of heat per 1 kW of electricity does not guarantee the actual ratio for a particular installation. When assessing performance, it is important to distinguish between the stated range and the system’s results under real-world conditions.
What affects efficiency and heating costs?
A heat pump’s efficiency and running costs depend on its heat source, the home’s heating needs and the system’s actual electricity consumption. Different systems produce different results: the materials provided state a range of 2,5–5 kW of heat for every kilowatt of electricity, while savings of up to 80% on heating costs are an upper estimate, not a guarantee for every home.
The heat source determines the operating conditions of the external loop: it can draw energy from outdoor air, the ground or water. The system then needs to transfer heat from that loop into the rooms; the required capacity depends on how much heat the home loses and how its heating system is designed. So the same equipment will not necessarily deliver the same efficiency in different buildings.
What you need to calculate costs
To estimate electricity costs, you need the heat pump’s actual electricity consumption and the electricity rate. The available materials provide neither figures for a specific home nor a rate, so it is impossible to calculate the bill in rubles; the range of 2,5–5 kW of heat per 1 kW of electricity does not determine the bill on its own.
- Heat source: outdoor air, ground or water—conditions for extracting energy through the external loop vary.
- Home’s heating needs: the amount of heat required and the design of the heating system affect how heat is delivered to the rooms.
- Running costs: calculating costs in rubles requires actual electricity consumption and the rate; an estimated saving of “up to 80%” is no substitute for these figures.
When might a heat pump fail to deliver the expected savings?
A heat pump may fail to deliver the expected savings if the “up to 80%” estimate is treated as a guarantee for every home: results depend on the starting conditions and the actual heating schedule. The stated efficiency range of 2,5–5 kW of heat per 1 kW of electricity also does not predict what a particular system will achieve in use.
What information is missing for an estimate?
Calculating monthly costs requires the electricity rate, the home’s heat demand and the pump’s operating schedule. Without these figures, it is impossible to reliably state a cost in rubles or determine how close actual savings will come to the upper estimate of 80%.
Before choosing equipment, check whether it suits your home in three respects:
- Heat source: air, ground or water—the option chosen determines where the system will draw heat from.
- External loop: clarify its design in advance; in the operating principle described, a non-freezing fluid circulates through the loop.
- Existing heating system: check that it is compatible with a heat pump rather than relying only on the range of 2,5–5 kW of heat per 1 kW of electricity.
How do heat sources for heat pumps differ?
Heat sources for heat pumps differ in where the system draws energy: outdoor air, the ground or water. An air-source system uses heat from the outdoor air, a ground-source system draws heat from the earth through an external loop, and a water-source system gets energy from water.
- Air: outdoor air serves as the heat source; this option does not use a separate ground loop.
- Ground: heat is supplied through an external loop laid in the ground. With this option, it is important to consider whether there is room for the loop on the property.
- Water: water becomes the heat source. Before choosing this option, check separately whether the specific property is suitable and whether the required connection design is feasible.
There is no universally best source among air, ground and water: resource availability and installation conditions vary from one property to another. Compare the options using two practical criteria: which source is available and how feasible it is to install the corresponding loop or connection.
What should you check before installing a heat pump?
Before installing a heat pump, clarify the heat source, the design of the external loop, the energy-use estimate for your home and the figures needed to assess payback. A pump can draw heat from air, ground or water: ask the contractor to explain which option the project specifies and why it suits the property and heating system.
- Heat source. Make sure the project specifies whether it uses air, ground or water, and exactly where the heat will come from.
- External loop. Clarify its design and the name of the non-freezing fluid. The loop circulates fluid that carries heat to the pump; when heat is extracted, the temperature of the glycol mixture may drop by approximately 4–6 °C.
- Estimate for your home. Request separate figures for expected electricity consumption and heat output, calculated for your specific home. The general guideline is 2,5–5 kW of heat for every 1 kW of electricity, but this alone is no substitute for an individual calculation.
- Savings and payback. Compare the forecast with your current heating costs and electricity rate. Without these figures, it is impossible to calculate the savings or payback period.
A promise to cut heating costs by up to 80% does not guarantee this result for a particular home: ask to see a calculation based on its consumption and electricity rate.
Frequently asked questions
Does a heat pump generate heat or move it?
How much electricity does a heat pump use?
Is it true that heating costs will fall by 80%?
Why does the external loop need non-freezing fluid?
Sources
- aircool.ru — “How a heat pump works”
- mammoth-russia.ru — “Heat pumps: how they work, pros and cons”
- geoteplo.by — “How a heat pump works: features — geoteplo”
- bendoregon.gov — “City of Bend energy efficiency”
- geotermal54.ru — “Heat pumps for home heating: types, pros and”
