If you are trying to set up HVAC for your building, then you have a lot of options to choose from, one of which is the heat pump.
What is a heat pump?
Heat pumps move heat from one place to another, effectively working as either a heater or an air conditioner, depending on your needs. The basic idea behind a heat pump is that it has two components, one on the inside of the building and one on the outside.
When you want to cool down a building during a hot summer, the heat pump will take some of the heat out of the air inside the building (through the internal component of the heat pump) and vent it outside (through the external component), where it will have a negligible impact on the environment. Conversely, if you want to heat up your building during winter, the heat pump will absorb some of the heat from the air outside and push that heat into the building.
What makes a heat pump different than a heater?
The basic difference is that a heat pump simply moves existing heat while a heater generates new heat. While heat pumps do generate a small amount of heat (since some amount of heat is generated whenever an appliance does work), they create a lot less than heaters. While your aim is to create a lot of heat, a heater can use a lot more power than you are comfortable paying.
On the other hand, heat pumps can't necessarily provide the amount of heat that you might need during particularly cold winters. Heat pumps become a lot less effective if the internal and external environments are drastically different. During a very cold winter, a heat pump will be a lot less efficient than a traditional heater.
What makes a heat pump different than an air conditioner?
Air conditioners and heat pumps can both be used for cooling a home, but they have some key differences. Both tend to use refrigerants during cooling cycles, but they differ in levels of efficiency. If you live in a temperate climate, then a heat pump will generally be a lot more efficient. This can save you a great deal of money in operating costs over the course of your lifetime.
However, as was mentioned earlier, heat pumps are quite inefficient when the climate outside is very different from the temperature that you want inside.
Read more about heat pumps here.