5 Five Applications of Heat Pumps
5 Five Applications of Heat Pumps: A heat pump works by using the refrigeration cycle to transfer thermal energy from outside to heat the building. It can also work in reverse by extracting heat from an enclosed space and releasing it outside to cool the area. Air conditioners are the type of units that only provide cooling. In heating mode, the refrigerant is compressed at the outside temperature, causing it to heat up and transfer thermal energy to the indoor unit. When the refrigerant is then moved outside, it decomposes and evaporates, resulting in a loss of thermal energy, causing it to become cooler than the surroundings. The refrigerant can then absorb energy from the air or ground before the process starts again. Electric energy is required to operate compressors, fans and pumps.
Air source heat pumps are the most common model, although there are other variations, such as ground source heat pumps, water source heat pumps, and exhaust air heat pumps. In district heating systems, heat pumps are also used on a large scale. The efficiency of a heat pump is measured by its coefficient of performance or seasonal coefficient of performance, with higher numbers indicating higher efficiency and lower energy consumption. In terms of space heating, heat pumps are generally more energy efficient than basic electrical resistance heaters.
Important Types of Heat Pumps
Geothermal heat pumps work by using a heat exchange fluid (usually water mixed with antifreeze) to extract heat from the ground or groundwater. The installation cost of geothermal heat pumps can be high. They can also be used to cool structures by moving heat from hot regions and transporting it into the ground through pipes located underground. A water source heat pump works in a similar way to a geothermal heat pump. However, it derives its heat from bodies of water rather than land. An essential criterion is that the body of water should be substantial enough to withstand the cooling effects of the unit and should not freeze or cause any negative effects.
The basic function of an air source heat pump is to transfer heat between two heat exchangers. Usually, one of the heat exchangers is located outside the building and comes with fins to force the air using a fan. Another heat exchanger is used to directly heat the air or water inside the building. This heated air or water is then circulated through heat emitters, which release heat around the building. An exhaust air heat pump is used to extract heat from the exhaust air of a building. However, they require mechanical ventilation. Two types of exhaust air heat pumps are available. The first is used to transfer heat to the intake air, while the second transfers heat to the heating circuit, including the domestic hot water tank.
A solar-assisted heat pump combines two systems, namely the heat pump and thermal solar panels, into a single integrated system. The solar thermal panel acts as a low-temperature heat source, while the heat generated is supplied to the evaporator of the heat pump. Absorption heat pumps, also known as gas-fired heat pumps, are a recently developed type of heat pump used primarily in residential systems. They rely on heat as their main energy source and can be coupled with a wide range of heat sources.
Important Applications of Heat Pumps
Heat pumps are typically used in regions with moderate demand for heating, ventilation, and air conditioning (HVAC) services; They can also serve as a source of domestic hot water and a means of drying clothes. Let us now examine the significant uses of heat pumps.
Space Heating and Cooling
Centralized heating systems use a single unit to generate heat which is then distributed throughout the interior of the home. These systems can use a variety of fuel sources, including oil, electricity, liquefied petroleum gas, and natural gas. Electric heating systems are considered a safe and hygienic option as they do not produce any harmful by-products. Despite its advantages, electricity can be more expensive than propane and oil. Additionally, electric HVAC systems can stop working during a power outage.
While oil and propane heating systems are efficient at converting fuel into heat, they require homeowners to have large storage tanks to accommodate the liquid fuel. On the other hand, natural gas heating systems can achieve fuel-to-heat conversion efficiencies of up to 99%, but they require a properly functioning ventilation system to release carbon monoxide gas. Propane, oil and gas systems are generally less expensive than electricity but are not as environmentally friendly. It is important to keep in mind that the prices of these fuel sources can be very volatile, which can make it challenging for homeowners to estimate their heating costs.