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Baldor Motors and Drives Are Key to Condominium's Goal to Save Energy and Water

The Villa Magna, a 92-unit luxury condominium in Highland Beach, Florida, sits between the Atlantic Ocean and the Intracoastal Waterway. When it was time for a major maintenance program to be carried out at the 30-year-old highrise, the Villa Magna condominium association approached repairs as a unique opportunity to improve the efficiency of systems in order to conserve water and energy. The results of their efforts have not only benefited their budget, but also the environment.

Bresnak Services Inc., a company that specializes in pumping systems for boosting water pressure in highrise buildings, did the work on a new domestic water supply system and an air conditioning condensation collection system at the condo. Gary Bresnak, managing director for Bresnak Services, says after investigating the existing water supply and air conditioning systems, he concluded that the primary problem with both was in their lack of controllability.

The system for boosting the pressure of the domestic water supply, which is a common feature in high-rise buildings, used two 25 HP pump motors running at full speed for 24 hours a day. The motors consumed 19 amps continuously, regardless of water demand. Pressure was controlled by mechanical regulators, an inefficient system that required regular and expensive maintenance.

Since modern domestic appliances are considerably more water efficient, Bresnak also judged the existing system to be far too large for what was required. For a more efficient and reliable solution, Bresnak replaced the fixed-speed 25 HP motors with 10 HP variable speed Baldor motors, controlled by Baldor drives.

“The drives’ V/Hz control mode enables motor speed to be controlled by feedback from a pressure sensor, to maintain constant water pressure under different flow rates,” explains Bresnak. “A time switch sets the duty cycle of each pump to 12 hours, to maximize reliability. Each motor consumes just 5.8 amps, which is less than a third of the energy demanded by the previous system.”

The condominium’s air conditioning system was equally inefficient. Water is pumped through heat exchangers in each of the building’s apartments, and then fed via a roof-mounted cooling tower before being fed back into the system. Bresnak found that the existing pump system used two 40 HP motors running at full speed from the 60 Hz supply, which consumed 80 amps. He also discovered that the flow rate was far too high, resulting in a temperature drop of only a few degrees in the cooling tower.

“By retrofitting the condenser pumps with Baldor motors and VS1PF bypass pump drives, we can now run the pumps at 50 Hz,” explains Bresnak. The result is that the current consumption has been dropped from 80 amps to 53 amps. Plus, we have been able to lower the flow rate to the point where there is now as much as 10 degrees heat loss in the cooling tower, rendering the entire building’s air conditioning system much more efficient.”

Another part of the project involved an air conditioning condensation collection system to help conserve water, a particularly valuable commodity in Florida. Instead of losing condensation down the drain, it’s now collected in a 400-gallon tank and then recycled back into the tower to further aid cooling. Bresnak says the goal is to introduce the cold water into the cooling tower at a slow rate.

“Again, my solution was to use another Baldor VS1PF bypass pump drive for the multistage pump,” says Bresnak. “By providing this very slow speed control, we can match the usage rate with the collection rate. This kind of control, allows us to slowly add the water as the cooling tower needs it without overflowing the tower and wasting any water.”

Results Show Up on the Bottom Line

Frank Strachan, Villa Magna’s building manager, couldn’t be more pleased with the results.

“The work carried out by Bresnak Services is saving us approximately $2,000 a month on our water bill,” says Strachan. “Over the last 12 months, we have also saved about $24,000 on electricity. These figures are considerably better than those achieved by some energy-saving schemes in other areas and says much for Bresnak’s ability to apply Baldor variable speed technology so knowledgeably.”

Strachan says the savings achieved so far have more than paid for the motors and drives. Now, with the investment paid for, he says he is looking forward to years and years of more savings.

“Saving energy and water is the right thing to do, and being green makes you feel good,” says Strachan. “But it also feels good to save money. This has been a win-win because we are conserving our water resources and using less electricity.”

These are just the kind of comments that Gary Bresnak wants to hear. He says his business relies on word of mouth, which means he strives to make the project as perfect as possible. Bresnak has used Baldor products for years, and with his reputation on the line, he says these are the products he’ll stick with.

“I have a good relationship with Baldor drives engineers,” claims Bresnak. “Baldor treats me as its partner and understands that I can’t have any problems out in the field. Whenever I call to talk through issues and need help, I get it, and that’s why I continue to choose Baldor products.”