CBE recently launched an online tool for designing with ceiling fans, making it easier for designers to create highly energy efficient and comfortable spaces. The tool was created based on years of research that have demonstrated that ceiling fans can keep a person cool while using only a fraction of the energy required by air conditioning. For example, some modern efficient fans can draw less than ten watts while providing cooling equivalent to a 6⁰F temperature drop. And in climates found in many parts of California and elsewhere, fans can allow for higher temperatures and expand the “free cooling” savings from air-side economizer operation.
CBE Professional Researcher Paul Raftery led the development of the tool, and was inspired by the desire to fill an important information gap. “There was very little public information available for designing with fans, people basically had to do CFD [computational fluid dynamics] or just guess,” he explains. Paul also notes that fans are a very cost-effective solution, especially in the context of HVAC costs, and may work well in existing buildings.
The tool performs airspeed calculations based on models that come from numerous full-scale laboratory tests. You can read more about the research behind the tool here.
The fan tool allows designers to quickly generate and iterate alternatives that meet given requirements and constraints. Users fill in room parameters, the fan types being considered, and other requirements, and the tool provides floorplan layouts and details. The tool is pre-populated with a set of fans with characteristics of nine anonymous (but real) fan products. Users can add specific fan products to be included in the tool’s calculations. The tool is complimented with a Ceiling Fan Design Guide.
Tool development was completed with support from PhD candidate Carlos Duarte. This work was funded as part of the project on Integrating Smart Ceiling Fans and Communicating Thermostats to Provide Energy-Efficient Comfort through the California Energy Commission EPIC Program, with match funding provided by CBE and Big Ass Fans.
Featured image: Laboratory set ups for fan studies in CBE’s test chamber.