# Heat pumps, air conditioning and refrigeration

Machines that move heat from cold to hot places, using a compressor.

Source page: https://www.materialinsights.org/energy/e_heat_pumps/

Conversion and use · Conversion devices · No. 104

- Conversion and use
 Conversion and use · Conversion devices · Foundation · Energy

A heat pump delivers about four units of heat for every unit of electricity, by moving warmth that is already outside.

Chart: Illustration: Heat pumps, air conditioning and refrigeration

##### Where it comes from

Chart: Map of where it comes from

A refrigerant boils at low temperature, soaking up outdoor heat even on cold days; a compressor squeezes it hot enough to warm a home.

##### Three things to know

1. The smaller the temperature lift, the better: the ideal COP is about 8.8 from 0 C air to 35 C underfloor water (calculated).
2. Heat pumps save households about USD 300 a year in the US to USD 900 in Europe against fossil heating (2022).
3. Industrial units can already deliver about 150 C, and machines above 160 C are expected commercially by 2027.

##### The journey

1. 1 **Outside heat**From air, ground or water
2. 2 **Evaporator**Refrigerant boils, soaking up that heat
3. 3 **Compressor**Squeezes vapour, raising its temperature
4. 4 **Condenser**Releases heat into rooms or water
5. 5 **Expansion valve**Cools refrigerant to start again

##### Go deeper pick a tab to open it in full

## Other sections

- [Overview](https://www.materialinsights.org/energy/e_heat_pumps/overview/index.md)
- [Correlation](https://www.materialinsights.org/energy/e_heat_pumps/correlation/index.md)
- [Science and limits](https://www.materialinsights.org/energy/e_heat_pumps/science/index.md)
- [Value chain](https://www.materialinsights.org/energy/e_heat_pumps/valuechain/index.md)
- [Unit economics](https://www.materialinsights.org/energy/e_heat_pumps/economics/index.md)
- [Engineering methods](https://www.materialinsights.org/energy/e_heat_pumps/methods/index.md)
- [Equipment and suppliers](https://www.materialinsights.org/energy/e_heat_pumps/equipment/index.md)
- [Relationships](https://www.materialinsights.org/energy/e_heat_pumps/links/index.md)