Cooling: The Removal of Heat

In order to understand the basics of cooling, it is important to understand that cooling involves the removal of heat, not the addition of cold. Technically speaking, there is no such thing as cold, only an absence of heat/energy.

August 19, 2015

In order to understand the basics of cooling, it is important to understand that cooling involves the removal of heat, not the addition of cold. Technically speaking, there is no such thing as cold, only an absence of heat/energy.

Thermodynamics

The rules that govern heating and cooling can be found in the physics of thermodynamics. For those not familiar, thermodynamics describes the movement of heat in nature and has three basic rules:

  1. Energy cannot be created or destroyed, it can only be moved or change form.
    1. The only way to cool an object down is to remove the heat (energy) from it. This requires the ability to move the heat to a different location or object or change the state of the original object (solid to liquid or liquid to gas) in a way that requires energy to do so. When a liquid changes to a vapor, it gives up heat in order to do so. In order to change back to a liquid, that vapor must absorb an equal amount of energy as it originally released.
    2. Pressure can be used to aid in the transformation of an object from one state to another (i.e. gas to liquid, etc…).
  2. Energy must flow from a higher state to a lower state. In other words, heat will always be transferred from a warmer object to a cooler object.
    1. Heat always moves from a hot material to a less hot material. Hot objects cool down because their heat is moving out of them into the cooler objects around them. Relatively cool objects warm up because the heat from other objects around them is moving into the cooler object.
  3. As a system moves toward Absolute Zero, the entropy of the system approaches a constant (minimum) value. In other words, the colder something becomes, the less change it is able to go through.
    1. Absolute Zero refers to the point at which atoms stop moving and is defined on the Kelvin scale as 0 K (not 0 degrees K). This point is physically impossible to reach, at -459.67°F (-273.15°C) and nothing can be colder than Absolute Zero. Any object above this temperature still contains heat, thus the above statement that technically speaking, there is no such thing as cold.

While the above overview provides a very basic understanding of thermodynamics and how cooling occurs, the main thing to remember is that removing the heat from a room does not simply involve blowing cold air into the room, it is a sophisticated process of removing the heat and transferring it elsewhere. Cooling is the removal of heat, not the addition of cold.

Share:

Featured Articles

What is MEP Engineering in Indoor Agriculture?

MEP engineers provide a wide range of engineering services necessary for any construction project, and they are especially critical when designing an energy efficient Controlled Environment Agriculture (CEA) grow facility. Here is what you need to know about MEP engineering in indoor farming.

5 Common Cultivation Facility Design Mistakes

Indoor agriculture facility design is far more complex than most other construction disciplines. It requires careful planning and support from specialized experts to set a grow up for success and longevity. There are 5 mistakes we commonly see when it comes to cultivation facility design.

Engineering Greatness: Meet Kenneth Loshelder, PE

Surna is extremely thankful for Kenneth and all that his team of engineers do for our company and for our clients. With over 15-years of experience, he has built a career focused on environmental consistency and energy efficiency. He encourages cultivators to engage with experienced mechanical engineers early-on in the buildout process. We asked Kenneth to answer some questions and lend valuable insight into the construction of cultivation facilities.

HVACD MEP Coordination for Cannabis Cultivation

Effective HVACD coordination is a key component in minimizing frustrating and costly construction delays in cannabis facility buildouts. There are a number of considerations your MEP team address in all stages of the project, from pre-design planning, to commissioning and beyond, in order to provide a comprehensive HVACD coordination effort.

Grow Room HVACD Maintenance Plans: Getting the Most Out of Your Investment

Without a proper HVACD system maintenance plan, your energy bill will increase, your equipment could fail, and your plants will suffer. Avoid these problems and keep your climate system in working order with the help of this guide.

5 Reasons Why Your HVACD System Isn’t Performing

Our recognition in the industry as the experts in cultivation climates means that we are often asked to diagnose performance failures in systems not of our design. When we audit these systems, we find there are common themes as to why they aren’t performing as expected. Let's discuss the most common reasons we find for issues with HVACD system performance.
Sign up to receive blogs and other news

© 2021 Surna. All rights reserved.

Surna Scroll to Top