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Guest Column - October 2016


Cost Calculators: The First Step to Reducing Operating Costs

By Mike Fowler

Every year, facility managers sit down to review their operating costs, and every year there is a huge figure that never seems to shrink: electricity. So much equipment uses electricity, and trying to simply "turn off the lights" doesn't seem to help. Everyone realizes that an aquatic facility's pump room is a big consumer of electricity, so it's a logical place to start when looking to reduce operating expenses. Luckily, there are now "cost calculators" in the marketplace that allow a facility manager to get details about where exactly that electricity is being used in the pump room. Many pool professionals use the figures they generate from these cost calculators as the basis for presenting the need to upgrade to more efficient equipment or add a variable frequency drive, and also to show prospective savings capabilities to an electric company to be approved for possible rebates for using more energy-efficient products or VFDs. Knowing the potential savings that will come from upgrading equipment is the first step in renovating an aquatic facility's pump room. When an aquatic facility sees that it can save from $300 to $1,000 a year in electricity, it becomes much easier to decide there is a need to upgrade pump room equipment.

What Is the Cost Calculator?

As the name implies, cost calculators are set up to calculate the cost of electricity by one particular piece of pump room equipment. Pumps are a great place to start because they are big electricity users. The calculator will start by asking questions about the facility—so be ready with how many gallons of water are in the pool and the turnover time of the pump. Calculators will also ask if there is a minimum required flow rate and the number of days the facility is open per year, and how long per day the facility is open and equipment runs. Be sure to have an electric bill handy to enter the cost per kWh of electricity and the horsepower of your existing pump. Calculators will even take into consideration the suction and return pipe size and the estimated flow rate. With this information the cost calculator can quickly identify power demand and energy use per day and more importantly, the cost by year. Comparing the figures of current equipment to the electricity usage figures of a new, energy-efficient pump puts the savings figures in black and white.

Commercial Aquatic Facilities & Utilities

The news continues to point out that the U.S. electrical grid is stressed. With an aging infrastructure and constrained capacity, utility providers are looking for ways to get rapid reductions in the amount of power they need to provide. With more than 322,000 commercial aquatic facilities in the United States, pumping 70 billion gallons of water, utilities are looking at commercial aquatic pump rooms as an area where they can get quick reductions in power demand. If you assume an average figure of $0.0583 per kW with a 7.63 HP per every 100,000 gallons of water, a 20 percent speed reduction for one hour would free up four medium-sized power plants. If you reduced the pump speed by 50 percent for 1 hour, aquatic facility pump rooms would free up seven medium-sized power plants.

CPS Energy, a local utility provider in San Antonio, Texas, is an example of a utility looking for quick reductions in power usage. Texas has one of the largest installed number of commercial pools in the nation with well over 30,000 installed pools as of 2012. The City of San Antonio worked with CPS Energy to reduce the city's energy usage. After doing an initial energy audit of the city, using tools similar to those of a typical cost calculator, the city determined that by retrofitting 22 city-owned pools, the utility would experience a dramatic reduction in energy demand and the city would get a payback on the project in less than one year! The 22 city pools primarily worked to reduce the speed of their pumps. They did this by replacing older pumps and installing variable frequency drives. The total project cost, for equipment and labor, was $137,000. However the annual electrical savings was $63,000, and CPS gave the city of San Antonio a rebate of $87,000. This gave the city a payback on the project of just nine months and a five-year return on investment (ROI) of 530 percent.