Alaska News

Using microturbines to drastically cut energy bill at popular Alaska waterpark

Three years ago, Dennis Prendeville was headed out the door for a meeting with Chugach Electric, when he noticed a heating bill on his desk. The bill, from Enstar, the local natural gas utility, was for one month of gas heating for his 56,000-square-foot H2Oasis water park. The charge? $25,000.

"I threw (the bill) down on the table and said 'no more'," said Prendeville, the CEO and president of the Alaska Waterpark Company, which owns and operates H2Oasis, Alaska's only indoor water park.

The meeting with Chugach was spurred by Prendeville's ongoing efforts to install a series of 65- and 60-kilowatt Capstone MicroTurbine dual heat and power generators. The turbines, essentially jet-engines that can run off of most fuel sources, are fairly rare in Alaska. There are just 50 to 80 of them in the state according to Greg Porter, president of Chenega Energy, LLC, the only authorized Capstone microturbine distributor in Alaska, with their use mostly limited to oil-and-gas companies and military operations.

Prendeville's is one of the largest microturbine operations in the state and the first to come online into the Chugach Electric Association grid. While the park does purchase some power for the Southcentral utility, most comes from the turbines.

Huge needs, easy decision

Buying into the turbines made sense, Prendeville said. He knew the water park -- with its massive energy needs -- would need some sort of co-generation to keep costs affordable. The park itself occupies almost an entire acre of space. It contains 350,000 gallons of water to run its numerous water slides, pools and "lazy" river that snakes around the edge of the park. The park's crown jewel, a 505-foot long "Master Blaster" water slide that shoots people around the park from 43-feet in the air, is fed with 5,500 gallons of water a minute.

But beyond the sheer size of the park and all the moving water, there's the challenge of keeping the place warm. Everything -- the building, floors and water -- is kept at a balmy 84 degrees all year, an expensive prospect given Anchorage's long, cold winters.

So for Prendeville, a former electrical engineer for Alyeska Pipeline Services, it came down to consolidating resources.


"There wasn't a startling moment," Prendeville said on the decision to go with the microturbines. "I just assumed we should be able to produce heat and power in the same way."

Since installing the generators three years ago, Prendeville has saved thousands of dollars. With an initial investment of $350,000 for the entire set up, he's making good on his purchase. In 2009, before the generators were installed, the park spent $371,000 on energy. By January of this year, the park spent $258,350 over the previous 12 months. So far, he's saved over $135,000 in three years, and is optimistic that the turbines will save him more than a million dollars in a few more years.

Big savings from a little ingenuity

Saving energy is a big deal for Prendeville. Do a quick tour around H2Oasis, a huge cavernous building in South Anchorage, and you'll see little hints of efficiency everywhere. Between the plastic palm trees and pirate ship décor, there are automatic lights in back rooms. On the roof, Prendeville keeps 60 4-by-12-foot solar panels that heat water during the summer. A makeshift system of tarps and siding directs warm air from microturbines generate back into the building's air intake -- saving a degree or two in heating costs.

"I don't like paying for power if we don't need it," he said.

Prendeville has four generators, but primarily uses two with the third and fourth on backup. The first, a 65-kilowatt-hour machine, was purchased new, but the other two were older models he purchased on eBay. The fourth, a recent purchase, came from the New Jersey shore.

The sleek and modern microturbines offer a steep juxtaposition between the old pool heaters Prendeville keeps around in case of an emergency. While built to run off of natural gas, the big, black pumps, with their large hoods and imposing size, look like they'd be better served by coal.

Through a series of jury-rigged devices, Prendeville has adapted the heaters to power the entire building. Warm water runs through tubes that provide radiant heat to the park's cement floor, while siphoning water off to the pool. Prendeville even tried using the same system to heat the sidewalk outside of the park. That didn't work, but he has plans to continue working on it.

The four generators, which run off of essentially a natural gas-powered jet engine, require little upkeep. They're controlled by systems within the water park and remotely by the company's manufacturer in California. Prendeville said in three years the biggest challenge he's had in upkeep was when a small fan broke on one of the units.

Other applications in Alaska

Prendeville is not seeking to be an independent power producer who sends power back into the grid. H2Oasis is still receives some power from Chugach Electric, but Prendeville said it's "virtually nothing." While the park does produce some power that gets sent back to Chugach, Prendeville's goal is to produce just enough power to keep his park running.

While Chugach had some initial concerns about the safety of the project, Prendeville said they came around.

"We were breaking the ice," he said.

Porter, with Chenega Energy, said he often uses H2Oasis as an example of how efficient the generators can be.

"It could be a grocery story, but it just happens to be a water park," he said.

He said the generators have been in Alaska for more than a decade, but haven't proliferated because of technology. In the early 2000s, the technology was unproven and of questionable reliability. That's changed since then, he said, noting that 36 of 37 microturbines on the Jersey Shore kept running -- even as the boardwalk was battered by Hurricane Sandy.

"(Now) the technology is not on trial," Porter said. "We're changing a culture and thought process in Alaska."

Chenega is working to sell machines across the state, noting the versatility of their applications and clean-burning technology. Oil and gas companies use the turbines to run platforms in Cook Inlet. Telecoms use them to power remote communications towers. Porter said Chenega recently partnered with the Alaska Department of Transportation to install the turbines in remote camps across the state.

"In a year, microturbines will be a household name," Porter predicted. "If it's not, then it will be in two."


Prendeville's interest is focused on making the most efficient use of his resources. Standing next to his turbines last week, he was asked whether the turbines were like his children. He smiled and warmly placed his hand on one of them.

"Maybe a little bit."

Contact Suzanna Caldwell at suzanna(at)

Suzanna Caldwell

Suzanna Caldwell is a former reporter for Alaska Dispatch News and Alaska Dispatch. She left the ADN in 2017.