New Ways to Save
Improving Efficiency in Pool Operations
By Chris Gelbach
The Pros and Cons of Pool Covers
Pool covers are another great way for facilities to save money. At Penn State, the university's outdoor 50-meter pool can cost more than $12,000 in heating costs in months like April or October. "With pool covers on we can drop that to $5,000 or $6,000, depending on how cold it is outside," said DeRosa. "So in one year alone in just two or three months, we can see a $10,000 to $15,000 energy savings, which over two years covers the cost of purchasing the blankets." The pool also experiences more modest savings by using the covers in May and June before typically putting them away for the hotter months of July and August.
The covers are not without their detractors, however, a group that may include pretty much anyone who has ever put one on. "We know that pool blankets have proven themselves," said Dittmar. "But pool blankets are awful to put on. It's horrible. It's difficult. It's heavy." Dittmar has even had staff members come to her and tell her that they can't work closing shifts anymore because they can't handle putting on the pool covers.
It's less of an issue with the morning shift, because the facility has an automatic pool cover winder that can do all of the heavy lifting in getting the pool covers off. "So we're halfway to having some innovation for pool covers," Dittmar said. "We know that they're great [in terms of cost savings]. We have something that will take them off. But putting them on is the hardest job. And no one has come up with a better way to do it yet."
The pool's filtration system can offer another significant opportunity for savings through options that offer the potential for water conservation and for reduced staff activity. Opting for a regenerative, diatomaceous earth (DE) filter over a traditional sand filter can create significant water savings by reducing the need for backwashes and accompanying water that's discharged to waste. Additional energy savings can be realized by not having to heat and treat the water that replaces the discharged water.
According to DeRosa, additional benefits of a DE filter can include increased filtration capabilities, including the ability to capture germs such as Cryptosporidium in the filter media, and the ability to filter a finer particulate than a sand filter can, potentially resulting in clearer water. DE filters also typically require a smaller footprint in the facility than traditional sand filters do. They can also help facilities gain points toward LEED certification. But they're expensive.
"I think your budget determines what you can afford," DeRosa said. "Some would argue that DEs are a better filtration media, that they're more environmentally friendly and give you cleaner and clearer water. That said, at our indoor pools at Penn State, we're still on sand, and our water is crystal clear and we maintain it properly. Sand filtration is a good standby, but we do discharge water to waste."
In existing facilities, DeRosa sees recreation managers opting for in-kind replacement of the filtration system because of budget considerations. "That said, any new waterpark that's being built will almost exclusively run with this new [DE] technology," he said.
Automation Options for Efficiency
While automation systems to control the backwash for the filtration system exist, Fowler doesn't see them employed often in commercial applications. According to DeRosa and Dittmar, the embrace of chemical controllers is significantly more widespread.
Benefits of chemical automation include more consistent application of chemicals, reduced risk of disease transmission in the water, and reduced staff requirements for chemical application and monitoring. In addition to allowing for online control capabilities, automation also enables more precise adjustment of chemicals to prevent chloramine buildups that require pool closure and negatively affect revenue.
At Penn State, DeRosa and staff monitor the water of the outdoor pool using a controller that handles both PPM (parts per million of chlorine) and ORP (oxidation reduction potential) sensors. "I think that most pools can get by with either, and for the average pool operator, PPM might be the better choice, because it measures quantity [of chlorine] and that's what they're interested in," DeRosa said. "But someone who really wants to understand what's going in their water might be interested in having both."
Fowler also recommends that facilities weigh the pros and cons of a UV or ozone system for secondary disinfection. "They can reduce the amount of chlorine usage by as much as 50 percent," Fowler said. "It's going to be more expensive, but you get the peace of mind that you're only putting in the amount of chemicals that you need to, and in the long run, it's going to save you money."