freecooling

Freecooling, also known as economizing or ambient economizing, is an energy efficiency technique that utilizes cool outside air to cool the interior of a building. Instead of relying solely on mechanical refrigeration systems, free cooling systems leverage naturally occurring low temperatures to achieve cooling. This is typically done by drawing in cooler outdoor air directly into the building's ventilation system when the outdoor air temperature and humidity are suitable.

There are two primary types of free cooling: air-side and water-side. Air-side free cooling involves using outdoor air to directly cool the building's interior, often through an economizer mode in an air handling unit. When the outside air is cooler and drier than the return air from the building, the system can reduce or even shut off the mechanical cooling components and simply ventilate with the cooler outside air. Water-side free cooling involves using cool water from an external source, such as a cooling tower or a nearby body of water, to cool the building's chilled water loop, thereby reducing the load on the mechanical chiller.

The effectiveness of free cooling is dependent on the climate and the specific design of the building and its HVAC system. In regions with consistently cool ambient temperatures, free cooling can significantly reduce energy consumption and operational costs associated with air conditioning. It contributes to sustainability by lowering greenhouse gas emissions and reducing the demand on the electrical grid. Regular maintenance and proper control strategies are crucial for optimizing the performance and benefits of free cooling systems.