One of the benefits of being a Certified Energy Manger (CEM) at Big Ass Fans is that not only do we get to help customers save energy, but we often get to work on our own energy conservation projects. Recently, we have been evaluating replacing some of the lighting in our 100,000 sq. ft. manufacturing building to save energy, reduce operating costs, and decrease our carbon footprint. While reviewing the energy simulations of the retrofit project, we noticed that the savings were not as significant as we had anticipated.

On the cooling side, the simulations were showing an annual savings of roughly $9,000 on the reduction in lighting energy usage plus another $200 in annual savings from the reduced air conditioning load in the office areas.

Unfortunately, the savings from the reduction in lighting energy also meant a reduction in the heat sources in the winter months. This decrease in internal heat gain was forcing the heating system to work harder, which offset roughly 15% of the savings. Fortunately, when the heat recirculation provided by the installation of a couple of Big Ass Fans was factored into the simulation, the fans not only offset the increased heating cost, but added additional savings to the energy conservation project. Pairing the energy savings from the Big Ass Fans with the lighting retrofit will hopefully add to our growing list of sustainable initiatives.

Energy savings and sustainability can come from many different places, not just from using Big Ass Fans. What are some of the ways you are increasing your efficiency while decreasing your carbon footprint?

Heat circulation, heat recirculation, heat distribution, destratification…regardless of your preferred description, they all work the same way. With winter upon us, there is no reason for your Big Ass Fan to sit idle. The benefits of ceiling fans during the summer are well known and appreciated by many. Not so common, however, are the benefits of Big Ass Fans in the winter to improve comfort and reduce energy costs.

Stratified Space

Less dense than cold air, hot air will rise and remain at the ceiling, (Fig. 1), keeping your ceiling comfortable and warm. This benefits…no one, aside from a few nesting bugs. Heat recirculation is the process of mixing the air to evenly distribute heat trapped near your ceiling down to the occupants, rather than escaping through the roof for good.

Big Ass Fans® are designed to operate efficiently at low speeds, so turning the fan very slowly in the forward direction (counterclockwise) will provide enough air movement to circulate the hot air at the ceiling down to the floor without causing drafts. Regardless of the square footage or ceiling height within your space, the goal is to mix the air in the space and keep the air speed at the floor below perceptible levels, approximately 40 feet per minute or ½ mph.

Hot air emerging from your furnace is approximately 5-7% lighter than the air present in the room. As this hot air rises, it contributes to a significant temperature difference between the floor and the ceiling, further increasing the workload on your furnace, not to mention increasing your energy bill.

Destratified Space

Running your Big Ass Fan in the winter months will result in an equalized air temperature throughout (Fig. 2). Considering all the heat supplied by the furnace now reaches the occupants and the thermostat, the furnace will run less frequently with less heat escaping through the roof.

“We have been using the Big Ass Fans for heat stratification in the winter time,” said Mike Donnelly, Vice President / General Manager for Lock, Joint, Tube in Chattanooga, Tenn. “We do have equipment inside the building that generates heat but no heating register so we are able to bring that heat back down from the ceiling. It is because of the fans that I took out the heating system,” he added.