Heat Pumps and Its Importance

Through the years, heat pumps have become one of the major necessities in every household and commercial establishment. Basically, heat pumps are devices or machines that are used to transfer thermal energy from the source to the sink using a small amount of energy. The source is usually characterized by an environment where heat can be extracted from. The most common examples of heat pumps are refrigerators, freezers and air conditioners. They are mainly used to provide optimum comforts even during the hottest days of summer and coolest days of winter because they used for heating or cooling an environment.

Heat pumps are popular choice for heating and cooling systems in residential and commercial areas because of its cost effectiveness and cost-efficiency compared to conventional heating systems. Air conditioner, refrigerators and heat pump work almost in the same ways. However, heat pumps are far better option than air conditioners because with heat pumps, you need not to install separate heating and cooling systems inside the house.  Also, heat pumps are getting more in demand on the market today of its efficiency in providing comfort, coolness and warmth inside the house when the need arises. A heat pump becomes cost effective if it is used all year round especially during winter and summer seasons.

Heat pumps have only two categories, namely, absorption heat pumps and compression heat pumps. Absorption heat pumps operate through the use of burnable fuels while compression heat pumps run only through the use of electricity. Through the alternating process of condensation and evaporation of refrigerant, heating and cooling inside the house are achieved. Basically, a heat pump is composed of outdoor coil, indoor coil, refrigerant and a compressor. No matter how cold it is outside, there is always heat that can be extracted from the environment. The outdoor coil is responsible for drawing heat from the environment while the compressor pushes the refrigerant through the condenser and evaporator. A condenser is a coil that absorbs the heat of the refrigerant and turns it into a liquid while an evaporator is a coil that helps the refrigerant takes heat from the environment.

During winter season, heat pumps provide comfort by spreading warmth in the entire household. In a heating mode, the outdoor coil acts as the evaporator while the indoor coil serves as the condenser.  During cool days, heat pumps will capture heat from the environment through its outdoor coil. When the heat meets the cool refrigerant, it converts the refrigerant into a warm vapor that would eventually flow through the indoor coil. When the warm vapor meets the indoor air, this makes the room even warmer.

During summer season where the temperature is relatively higher than normal, heat pumps also come in rescue to provide optimum comfort. During summer days, the outdoor coil serves as a condenser while the indoor coil serves as the evaporator. A heat pump captures the heat from the environment through its outdoor coil. When the heat meets the cool refrigerant, it loses its humidity and it causes the refrigerant to turn from liquid to vapor. The vapor will flow through the outdoor coil where it dissipates heat. In effect, the liquid turns into a liquid again which would travel through the liquid line until it reaches the indoor coil. This lowers the temperature inside the room during the summer days. The indoor coil serves as the evaporator by absorbing the heat from the inside and injects it into the outside environment.

Heat pumps are considered to be best and cost-effective investments in every household provided that the house does not have holes, cracks and leakage where relatively huge amount of air can pass through. Heat pumps can significantly reduce the energy cost of every household despite the fact that they require electricity to operate. The machine makes use of limitless supply of free clean heat from the environment and would only require you to pay for the energy that was used in transporting the heat. Also, heat pumps have a normal life span of 10-15 years, thus you are able to benefit from it for a longer period of time.

Compared to geothermal heat pumps, consumers are better off with air-source heat pumps. Installation of geothermal heat pumps can be twice as expensive as the installation of air-source heat pumps. Geothermal heat pump installation can incur a cost of as much as R12,000 to R20,500 while air source heat pump installation will only generate a cost of R8,500-R15,000. Running a geothermal heat pump installation is cheaper compared to air-source heat pump, but when repair and maintenance are considered, the former is more expensive.  Operating a ground-source heat pump is cheaper than air-source heat pumps because the temperature in the ground is almost constant all the time. It is estimated that an individual can save around 30%-40% on his utility bill with the help of heat pumps.

The Energy Savings Trust also revealed that replacing a gas heating to air source heat pumps can save an individual as much as R1200.00 in a year while replacing a solid fuel heating with ground source heat pumps can save a cost of around R6000.00. Heat pumps are cost effective because it only transfers heat instead of burning it. In heating a room, a typical heat pump has coefficient of performance (COP) of 3-4 while an electric resistance heater has 1.0 COP. Coefficient of performance is the ratio of heat movement to its input. This simply means that heat pumps are far better than heaters when it comes to energy efficiency. However, heat pumps operate more efficiently in high temperature areas compared to low temperature ones.

Almost all kinds and types of heat pumps are energy efficient. In fact for every kilowatt of electricity the machine uses, heat pumps are capable of producing 2-5 kilowatts of heat.  Consumers can also save from their electric bills because heat pumps are 56% more energy efficient to operate than gas boilers. Furthermore, you can take advantage of your heat pumps at no cost at all if you use renewable source of energy such as the sun.

I have found 2 good video to explain how a heat pump works. These are from abroad, but applicable to South Africa.

And here is more info. It amazed me to find that a heat pump is even more economical than gas in the UK! See video below.

Please contact us with any questions you might have about heat pumps for your house.