temperatures to lower temperature areas. Heat doesn’t transfer from lower to higher temperature areas without any additional work. 

A heat pump plays a crucial role in controlling a building’s temperature. It transfers heat caused due to high temperature from the outside to the inside, using electrical energy. Heat pumps are responsible for providing a suitable temperature to your place.

What is a heat pump?

A heat pump is defined as a device used to move heat from one place to another by using electrical energy or mechanical energy.

A heat pump has the opposite working principle of heat engines, which means electrical or mechanical energy is converted into thermal energy in a heat pump.

The efficiency of a heat pump is denoted as a coefficient of Performance (COP). Therefore, pumps with a higher COP will consume less energy.

Types of heat pumps

Heat pumps are mainly classified as follows:

1. Air-source heat pumps
2. Ground source (Geothermal) heat pumps
3. Exhaust air heat pumps
4. Solar-assisted heat pumps
5. Water source heat pumps
6. Hybrid heat pumps

1. Air-source heat pumps (ASHP)

An air-source heat pump is a heat pump where atmospheric air is used as a primary energy source to transfer heat from one place to another. It is easy to install in a residential area since it does not require any medium like a canal. An air-source heat pump can operate till -20 degrees Celsius.

Advantages of air-source heat pumps:

• Easy to install.
• A medium like a bore well, the canal, is not required.
• It can provide three times more heat energy than Electrical energy it consumes.
• Less space is required.
• More efficient.

Disadvantages of air-source heat pumps:

• Required to insulate the area.
• Upfront cost.
• It can be noisy.

Applications:

• Residential air conditioning.
• Commercial.

Classifications of air-source heat pumps

Air-source heat pumps can be classified as follows:

i. Ductless air-source heat pumps:

 A ductless air-source heat pump is easy to install. It will require a three-inch hole over the wall to connect the condenser located outside the room and head placed inside the room. Ductless systems can be installed multiple times as per the requirement based on room space. 

ii. Ducted system air-source heat pumps:

If your home has an existing ventilation system, this is the best option. It can connect every room by duct. In this system, the temperature of all systems can operate from single operating units.

A ducted system will provide consistent heat to every room. However, this system will have more running costs than a ductless air source.

iii. Single zone system:

As the name suggests, a single-zone system is used to heat one room with one indoor heat and one outdoor condenser.

iv. Multi-zone system:

A single condenser can connect multiple indoor coils in a multi-zone system, controlling each room’s temperature based on comfort. This system is also known as a “Single head” or “single port” system.

2. Ground source (Geo-Thermal) heat pumps (GSHP)

Ground source heat pumps transfer heat between the room and ground or a nearby water source. The ground source has a higher installation cost, but the operating cost is less since it absorbs heat from the ground or water source temperature. It is used to melt snow in extreme climate areas.

Advantages of ground source heat pumps:

• Less operating cost.
• Operate in extreme climate change.
• Environmental Friendly.

Disadvantages of ground source heat pumps:

• Restricted location.
• The upfront cost is high.
• Landscape alteration may be required.

Applications:

• Pool heating.
• Extreme climate change areas are residential buildings.

3. Exhaust air heat pumps (EAHP)

In exhaust air heat pumps, heat is absorbed from exhausted air from buildings and made helpful in work. These pumps extract air through a series of ventilation ducts provided from moisture producing rooms.

Exhaust air heat pumps contain hot water cylinders, heating coil, extractor and heat pump components.

When the heat energy is passed through a heating exchanger, which will convert heat energy to the refrigerant, the refrigerant will evaporate and compress in the form of gas. As a result, the heat energy is produced as per the requirement.

Advantages of exhaust air heat pumps:

• Reduce C02 emissions.
• Continuous ventilation.
• Reduce Fuel bill.

Disadvantages of exhaust air heat pumps:

• Not efficient in extreme Climate conditions.
• Installation cost is high.

Applications:

• Space heating.
• Domestic water heating.

4. Solar-assisted heat Pumps (SAHP)

Solar-assisted heat pumps are the integration of solar panels and heat pumps. In these pumps, thermal energy absorbed from the sun is used to supply the required heat. These pumps are also known as “Thermodynamic panels”.

Advantages of solar assisted heat pumps:

• Quiet operation.
• Reliable Energy source
• Less carbon emission.
• Reduce household energy consumption

Disadvantages of solar assisted heat pumps:

• High initial cost.
• Less efficient while the sun is away.
• Difficult to install.

5. Water source heat pumps (WSHP)

These pumps are similar to ground source heat pumps. Here, energy is absorbed from nearby water sources like ponds or lakes.

Generally, closed loops submerged pipes carry energy from water sources and are transferred to the heat pump. This will compress and expand to boost energy to the required heat.

Advantages of water source heat pumps:

• Reliable.
• Energy-saving.

Disadvantages of water source heat pumps:

• Not efficient to heat
• More land work needed to install pipes

6. Hybrid heat pumps 

Hybrid heat pumps use both fossil fuel and renewable sources to produce energy.

Advantages of hybrid heat pumps:

• Suitable for the weather.
• Highly efficient.
• Reduce running costs.

Disadvantages of hybrid heat pumps:

• Installation cost is high.

Conclusion

A heat pump is a device used to transfer heat from one place to another. A heat pump is classified into many types based on the purpose of primary energy sources. The main categories of heat pumps are air-source heat pumps, ground-source (geothermal) heat pumps, exhaust air heat pumps, solar-assisted heat pumps, water source heat pumps and hybrid heat pumps.