HVAC: Cooling systems
HVAC systems consume 25% to 30% of the energy in a typical commercial building; functionally intensive buildings (industrial facilities, laboratory buildings, hospitals, data centers, etc.) with controlled environments and large process loads can consume more than this. Generally, 50% of the HVAC energy is used for cooling purposes. Providing cooling comfort and energy efficiency in nonresidential buildings is an ongoing challenge for mechanical engineers. Emphasis on building performance and adoption of energy-efficient building codes is increasing. Designs are based on a host of variables beyond space type and understood loads including operating costs, first cost, lifecycle cost, and measurement and verification (M&V) requirements.
Demand for historically typical cooling technologies, such as variable-air-volume (VAV) and water-cooled chillers, is giving way to a variety of systems, such as displacement ventilation, geo-exchange, simultaneous heating/cooling systems, variable refrigerant flow (VRF), passive design, chilled beams, dedicated outdoor air systems, and evaporative cooling.
- Explain the applicable codes and standards: ASHRAE Standard 90.1: Energy Standard for Buildings Except Low-Rise Residential Buildings, California Title 24, ASHRAE Standard 189.1-2014, Standard for the Design of High-Performance Green Buildings, and International Energy Conservation Code (IECC).
- Acquire a basic understanding of the various cooling technologies and systems, with an emphasis on comparative efficiency.
- Analyze the pros and cons of cooling technologies for various building applications.
- Compare a variety of systems via case studies and engineering projects.
Rodney V. Oathout, PE, CEM, LEED AP, Principal, Regional Engineering Leader, DLR Group, Overland Park, Kan.
Jason Atkisson, PE, HBDP, Project Manager, Affiliated Engineers Inc., Madison, Wis.
Moderator: Jack Smith, Content Manager, Consulting-Specifying Engineer, CFE Media