Ceiling fans may be associated with the warmer months, but, in fact, aid in temperature control year-round. During the colder months, fans facilitate a more even circulation and distribution of warm air, maximizing the effectiveness of a home's heating system. Winter thermostat temperatures may be lowered a few degrees with the inclusion of a ceiling fan, reducing energy consumption without comprising warmth.
Conversely, using a fan in conjunction with air conditioning during summer months produces a wind chill that allows for higher temperature settings on air conditioners while still providing the desired cooling effect commensurate with lower settings.
A fan's energy efficiency is related to its motor and light source. DC motors consume 70% less power than regular ceiling fan motors (with the added bonus of a smaller, lower profile form). LED light sources use less wattage than conventional light bulbs, further reducing energy consumption.
Determining a fans efficacy has never been easier - fan packaging and specs include an energy usage label. The label shows Airflow (measured in Cubic Feet Per Minute), Electricity Usage (measured in watts and excludes light source), and the Air Flow Efficiency (CFM/Watts) - the higher this number, the more efficient the fan. Keep in mind - the larger the blade diameter, the higher the Air Flow Efficiency number.