Cooling production with heat pumps

In recent days, Europe has been hit by an intense and worrying heatwave that has left record temperatures and extreme weather conditions in its wake. This heatwave, which has affected much of the continent, poses a new challenge for the HVAC industry.?

This is where the magic word "HEAT PUMP" comes up again, which, as many of you already know, not only produces heat but also cold. Most of you already know this, but for those of you who don't, the heat pump works by extracting heat from the surrounding environment, even at apparently high temperatures, by means of a cooling fluid. This fluid is pumped through a thermodynamic cycle, where it is repeatedly compressed and expanded. During compression, the fluid is heated and releases the absorbed heat into the environment. Then, via a heat exchanger, the fluid expands and cools the desired space considerably.?

INSIDE THE VIDEO!

When it comes to cooling with a heat pump, there are two main approaches: active cooling and passive cooling, also known as free cooling.

Active cooling refers to the process in which the heat pump uses its cooling capacity to actively reduce the ambient temperature. This is achieved by extracting heat from the surrounding air and transferring it to another location, usually outdoors, through the thermodynamic cycle of the heat pump. Active cooling is ideal for situations where precise temperature control is needed, such as in indoor spaces, offices or laboratories.

Passive cooling refers to the use of the heat pump to maintain a comfortable temperature without active cooling action. In this case, the heat pump must be water-to-water (this does not work in the ASHP) and what is done is to exchange the water contained in the collection circuit with the production system of the building, without operating the heat pump compressor.

The most compatible production systems are underfloor heating and cooling, yes cooling! and Fancoils.

Underfloor cooling is a system that uses pipes embedded in the floor to distribute cold water to cool the space. The cooling floor is efficient and provides a pleasant feeling of comfort, as it uses a large surface area (the floor) to distribute the cold evenly.

Fan convectors are air conditioning units that are used to cool or heat indoor spaces. In the case of cooling, chilled water from the cooling system circulates through the fan coil, cooling the air that is blown by the fan and distributed in the space. Fan convectors are commonly used in commercial and residential buildings, and offer a flexible and controlled solution for cooling different areas.

The closer the brine and production temperature are, the higher the efficiency of the heat pump is. This relation is applicable to both heating and cooling production.

Cooling: Higher efficiency with high production temperatures (UFC, 18-20oC)

Do you want to see a real example?

In the following screenshot from last year at a geothermal heat pump installation in Italy, we obtained the following results. The high COPs are due to the heat recovery process using HTR technology (a topic that deserves a separate article).

The same applies to the simultaneous production of heating and cooling, not to be confused with simultaneous consumption! In the next article, I will explain a little more about this application.

#heatpumps #heatingandcooling