NEW to New Zealand and creating significant interest in energy conservation are High-Volume/Low Speed (HV/LS) Revolution Ceiling Fans. Up to 7200mm in diameter, these fans effectively circulate air in industrial plants, warehouses and large facilities. When used properly in conjunction with conventional heating and cooling systems, they are a cost effective solution to air movement and better overall environmental control.

Revolution HV/LS fans have specific and often dramatic benefits when used in large facilities. They help make people more comfortable and productive, reduce energy costs and help with high-humidity or air movement problems.

During the heating season, there is often more than a 12-degree Celsius difference between floor and ceiling in most industrial plants and warehouses. This is a result of warm, light air rising and cold, heavy air setting. Typically, the air temperature will be one to 1.5 degrees Celsius warmer for every metre in height. As such, a heating system must work hard for extended periods to maintain the temperature near the floor, or at the thermostat set point, wasting precious energy and dollars.

To address the issue, Revolution ceiling fans gently move the warm air near the ceiling back down toward the floor. The air reaches the floor below the fan where it then moves horizontally a few feet above the floor. The air eventually rises to the ceiling where it is cycled downward again. This mixing effect creates a much more uniform air temperature, with perhaps a single degree difference from floor to ceiling. With the use of a Revolution fan, there is less of a burden on the heating system, saving energy and dollars.

Conventional high-speed ceiling fans have been used for many years. However, the smaller fans are ineffective in moving the warm air from ceiling to floor. A typical high-speed ceiling fan spreads the air out quickly as it moves away from the fan. The result is that little, if any, air reaches the floor.

Revolution fans also contribute to energy savings in air conditioned facilities during the warmer months. Because the light breeze moving across employees’ skin has a cooling effect, the thermostat can be raised without reducing the level of employee comfort. The wind from a Revolution fan allows up to a three-degree increase in thermostat setting with no change in employee comfort. Electric bill savings is 6.5 percent for each degree, saving up to 20 percent annually.

Employee comfort and productivity

A large majority of industrial plants and warehouse facilities are not air-conditioned. During the summer months, this can make for a very uncomfortable environment, resulting in a loss of productivity and employee morale.

According to the US Department of Health & Human Services paper “Workers in Hot Environments” a slow air speed can create a cooling effect of up to eight degrees Celsius. Air moving faster can be disruptive and provides little, if any added cooling benefit.

A NASA study found that as effective temperature rises, work output and accuracy plummet. A cooling sensation of seven to 11 degrees Fahrenheit can make workers ten to 35 percent more productive.

Whether it’s the heating or cooling season, Revolution fans are preferred over high-speed ceiling fans or floor fans when it comes to moving large volumes of air. Revolution fans move more air at the right speed – and get air where it’s needed – and do so with very little energy.

Unlike high-speed ceiling fans, technically advanced Revolution fans are able to move large volumes of air seven times the diameter of the fan. A single Revolution fan can replace as many as ten to 20 floor fans.

High-speed floor fans have several disadvantages when compared to Revolution ceiling fans. Specifically, they create a blast of wind for a relatively small area; they are noisy; they can be more disruptive; and they use more energy.

In addition, having multiple floor fans can increase clutter and the chance of mishaps involving equipment and electrical cords.

Revolution fans are also a worthwhile consideration for buildings where stagnant air creates an unhealthy environment. The fans can greatly improve air quality through better air circulation and are often the most cost-effective way to accomplish this in large open spaces.

Revolution fans can greatly reduce floor sweat due to variances in surface-to-air temperature. In addition, improved air circulation and ventilation helps keep products and packages dry, minimizing energy loss. It also improves quality control for stored products by keeping temperatures consistent form floor to ceiling.

Return on investment

Because Revolution fans are efficient, their return on initial investment often ranges from six months to two years. Payback varies according to a number of application variables. Winter energy savings are substantial. Users can reduce their heating bills by 20 to 30 percent.

There are a number of factors to consider when deciding how and when to use Revolution fans. They include obstructions such as pallet racks, machinery and product staging; personnel work areas; and overall building layout, to name a few. Larger diameter fans will move air further down rack aisles and over obstructions. Smaller diameter fans can be most effective in specific work areas, or where installation space is limited.

Fan suppliers can help configure an array of fans, determining the number, size and locations that provide the maximum benefit for the investment. They can also offer turnkey installation where on-site resources are not available. While the basic concept is similar across all Revolution fan manufacturers, fan design and performance are key factors to consider. There are significant differences between manufacturers, including the shape and number of blades, blade tilt, hub construction, blade-to-hub connection, and safety features. The performance of different designs will vary in the uniformity of air movement directly below the fan, as well as the height and reach of air movement outward from the fan’s diameter. Other important considerations included ease of installation, local support, trial program availability, and warranties.

The use of Revolution fans has gained increased attention in the HVAC world as a practical and affordable solution to improved air movement and overall better environmental control. These types of fans are now recognised as a valuable supplement to help facility managers control energy costs and improve employee comfort and productivity.

Email: don@totaldoorsltd.co.nz