Heat pump

Definition

A heat pump is a device that transfers thermal energy from a colder area to a hotter area by using mechanical work, often against the natural flow of heat. It can be used for heating or cooling purposes by either absorbing heat from outside and releasing it inside or vice versa.

5 Must Know Facts For Your Next Test

1. A heat pump operates based on the principles of thermodynamics, particularly the second law, which involves entropy and energy transfer.
2. The coefficient of performance (COP) for a heat pump is defined differently for heating and cooling modes; it is higher than 1 because it moves more energy than it consumes.
3. Heat pumps are more efficient in moderate climates where the temperature difference between inside and outside is not extreme.
4. The Carnot cycle provides an idealized model for the efficiency limits of real-world heat pumps.
5. A reversible heat pump can function both as a heater and an air conditioner.

Review Questions

• What principle of thermodynamics does a heat pump operate on?
• How is the coefficient of performance (COP) of a heat pump calculated?
• In what type of climate do heat pumps perform most efficiently?

Related terms

Coefficient of Performance (COP): A measure of a heat pump's efficiency, calculated as the ratio of useful heating or cooling provided to work required.

Carnot Cycle: An idealized thermodynamic cycle that provides the maximum possible efficiency for any engine operating between two temperatures.

Refrigerator: A device similar to a heat pump but typically used to remove thermal energy from an enclosed space and release it to its surroundings.