Currently, 43% of the electric energy produced in Brazil is consumed by industries. In order to keep the production lines working, the companies rely on electric power. According to ANEEL (National Agency of Electric Energy), 64% of the installed power capacity in the country comes from hydroelectric power plants, followed by thermoelectric power plants, with 28,83%, and small power plants, with 3,67%. Since water resources are less and less plentiful electric resources are threatened.
The Brazilian scenario has challenged the market to innovate and present alternatives to mitigate these problems. In response, WEG offers an industry efficient solution with a short term payback.
One of these solutions, being implemented at one of WEG’s manufacturing plants, has produced excellent results, both in power savings and the reduction of water consumption. For two years, the WEG Environment and Quality System Department monitored and compared the water and energy consumption of a Cooling Tower.
The first analysis of the study was carried out with the cooling tower operating with a standard efficiency motor without the use of a variable speed drive. In the second phase of the study, a WEG high efficiency solution was implemented with a W22 Premium Motor + CFW701 HVAC variable speed drive. This energy efficient solution reduced electric energy consumption by 48%. This economy was obtained because the cooling towers are subject to variable operating conditions according to the demands of the application and the ambient temperature of the atmosphere. In this case, the implemented solution recognized the variables and adjusted the fan/motor setting to deliver exactly what the application needed.
In addition to the lower energy consumption, this technology presented great savings of another valuable resource: water. After the implementation of the solution, there was a reduction of 22% in water consumption, because the fan started to control the water temperature according to the needs of the application (sometimes the water needs more cooling, sometimes less), and the evaporation, which before occurred in excess, was consequently reduced.
These analyses were evaluated by the manufacturer of the cooling tower with special attention to the differences in the production volume during each period so that the comparison would be made using the same basis.
The result was a savings of 1,170 liters of water a day, equivalent to 427 thousand liters of water a year. "Considering that cooling towers are very common pieces of equipment in industry, even in commercial companies and building installations a tremendous amount of water and energy can be saved using this solution. Take the example of a company that has five cooling towers, it would be possible to save about 2.14 million liters of water a year. With this amount of water it would be possible to supply 13 homes for 12 months," explains Leandro Avila da Silva, head of WEG Energy Efficiency Business Center.
The W22 Premium line of motors was developed focusing on energy efficiency, reduction of operating costs, quick payback and lower CO2 emissions. This line exceeds the standard efficiency levels of the market for electric motors. The CFW701 HVAC frequency inverter has specific functions to drive pumps and fans, resulting in a much more efficient operation in terms of power consumption then other competitive inverters.