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# Absorption Heat Pumps

When using an absorption heat pump, you don't use electricity to run it. Instead, you use a heat source, like natural gas or propane.

People use an ammonia-water absorption cycle to heat fabulous homes. A heat pump works like this. The refrigerant (ammonia) is condensed in one coil to release its heat; its pressure is reduced, and the refrigerant evaporates to take the heat. If the system takes heat from the inside of your home, it cools it down; if it releases heat into the interior of your home, it heats it.

Absorption heat pumps are different from other heat pumps because they don’t use a compressor to raise the ammonia pressure that evaporates. If you want to avoid this, put the ammonia into water, where a low-power pump can then pump the solution up to a higher pressure. That’s where the heat source comes in. The heat boils the ammonia out of the water, which starts the cycle over again as it did before.

## Example of absorption-type heat pump system

An example of a heat-pump that absorbs a heat amplifier is a type of single effect.

Here are some absorption heat pumps examples.

To make hot water for two different processes, heat cool water to 35°C.

1) 90°C-temperature hot water is used to clean the machine and tools in the production process.

2) Gallons of hot water at 60°C are used for the boiler to feed.

A machine type

An absorption heat-pump does this. This is a type of heat amplifier (Single effect).

In this case, the power is 1,300 kW.

COP: 1.75

Estimate conditions

The cost of a steam unit: 3.5/kg (Boiler steam)

6,000 hours of operation per year

Energy-saving effects

About 17 million yen in annual operating costs were cut

An example of a heat-pump that absorbs a heat amplifier is a type of double effect.

The electricity generator, the HRSG, and the air are all used to heat 40°C warm water.

A compressor converts 55°C hot water to cool air for comfort (heating).

The heat source unit

A heat pump that absorbs heat is a first-class heat pump (double-effect).

The heating capacity is 3,400kW.

COP: 2.3%

Estimate conditions

Price per kg of steam: 3.5 (Boiler steam)

3,000 hours of operation per year

Energy-saving effects

About 30 million yen in annual operating costs were cut.

## How Absorption Heat Pumps Work

People can buy absorption heat pumps in different ways:

• Air Source Heating Only – Absorption heater can heat space and water very well with gas.
• Air Source Heating/Cooling– Because the thermodynamic cycle is reversed, a gas-fired absorption heat pump can make both hot and cold water for space and water heating and cooling, at the same time, because it can turn on and off at will.
• Water Source – A gas absorption heat pump for geothermal systems that can heat or perfect space and water is made for this purpose.
• Simultaneous Heating & Cooling – Gas absorption heat pump that makes both hot and cold water simultaneously.
• Heat Pump Tank Water Heaters – People who have tank water heaters at home that use an absorption-based heat pump to heat the water in the tank have heaters that work very well.

There are systems called heat pumps that move heat from a lower temperature to a higher temperature by changing the flow of heat (heat is carried from warm mediums towards cooler ones). Whether one wants to heat or cool with a single piece of equipment, this flow capability will work for them.

Natural gas is heated with outside air or a geothermal loop (COP = 1.4) to make space and water heating possible. A heat pump that uses natural gas instead of electricity differs from a heat pump that uses electricity because of how much energy it needs. As an alternative to running on electricity, an absorption heat pump runs on gas in a premixing burner. This burner heats water and ammonia in a wholly sealed absorption circuit.

In general, absorption heat pumps are hydronic systems, like a boiler outside. They heat and cool the needed water, just like a boiler does. Because this feature lets you control the temperature at which heating and cooling come in, you can make more precise adjustments to the temperature in your home, which makes the whole system run more efficiently and more comfortable to use at all times.

## How Engine-Powered Heat Pumps Work

As you can see, many different types of engines run pumps.

• They only air source hot water
• The water comes from the air
• A source of water that can be used in geothermal systems
• VRF (Variable Refrigerant Flow systems)
• It can be both heated and cooled at the same time

It uses a very efficient reciprocating engine that runs on natural gas to make the shaft horsepower move a vapour compressor, which cools the air in your home. The compression cycle turns the refrigerant from a liquid to a gas in the heat pump cycle.

People around it get hot when it does this, but it makes more heat when gas is concentrated and turned into a liquid. The compressor, driven by an economic engine, moves the refrigerant through the gasification and liquefaction stages with these principles. This circulation helps to cool and heat things. An engine-driven heat pump has a significant advantage over an electric vapour compression heat pump because it costs less.

### Conclusion

Most heat pumps work by compressing, and they use electricity to do it. Refrigerant fluid is used to cool down the source of the lower heat. The liquid “takes in” heat and starts to boil even when the temperature is below 0° C. Then, the gas is compressed, which makes it even hotter. Heat exchanger coils are used to pass the gas through. There, the gas condenses, releasing the heat that was in it. When the process is done, it starts again.