How an Island Resort Saved $90,000 in Hot-Water Energy

By upgrading to a modern commercial tankless water-heating system, Turtle Bay Resort in Oahu, Hawaii, expects a three-year return on investment and vastly simplified controls and maintenance.

Brought to you by Propane Education & Research Council

Original article found on ArchitectMagazine.com

To see how far commercial water heating has come over the past generation, just look at the two sides of the boiler room at Turtle Bay Resort in Oahu, Hawaii. 

On one side sits the resort’s gargantuan previous system, waiting to be removed. Two large low-pressure boilers. each about the size of 1,000-gallon tanks with support equipment including feed pumps and softeners, stand next to two 900-gallon hot-water storage tanks with steam-injection bundles. 

On the other side in a large, open area sits the future: two small boxes with digital control panels, which supply the same amount of hot water.

The upgrade is part of a resort-wide transformation undertaken by its new owner, the New York–based BRE Hotels & Resorts, which acquired the hotel in 2017. The upgrades included a renovation that opens the lobby with massive ocean-facing windows and a sunken lobby bar dubbed Off the Lip, which overlooks the shoreline and an infinity-edge lagoon. The renovations are ongoing in guest rooms, meeting rooms, and the spa.

Even with those upgrades, it’s the behind-the-scenes renovations of systems like the water heating, drains, insulation, and plumbing that most excite facilities director Manny Crawford. “We finally got rid of everything from 1972,” he says. “Now it’s a 2021 upgrade. As a department, that’s probably one of our favorite things that happened through the renovation.”

Located on the remote northern tip of Oahu, Turtle Bay Resort relies on propane for water heating, fire pits, and commercial cooking.
Located on the remote northern tip of Oahu, Turtle Bay Resort relies on propane for water heating, fire pits, and commercial cooking.

Upgrading to tankless

Size wasn’t the only problem with the resort’s 40-year-old boilers. While Crawford’s team kept them in top condition, they required heavy maintenance and simply weren’t as efficient as modern systems. If occupancy was high, the system might struggle to meet the hot-water demand, and the facilities staff would have to manually adjust the valves to get more hot water into the tank or increase the fire rate.

“We always had a 900-gallon tank that we constantly had to warm up to get it delivered, especially if it was going to be used a lot,” Crawford says. “So that was killing us with [how much propane it used] because we always had to constantly reheat that water in that tank.”

Working with a local representative for the replacement project, the resort selected two 1.5-million-Btu, on-demand propane water heaters from the Galesburg, Ill.–based manufacturer Intellihot—a heavy-duty alternative to increasingly popular tankless water heater rack systems. The project’s installer, Tony Castaldi of Pacific Boiler in Kailua, Hawaii, sees the technology as a better, more-efficient alternative to boilers in this type of application.

The 1.5-million-Btu Intellihot water heaters fit into a 3-by-6-foot footprint, offering immense space savings compared with the previous boiler system.
The 1.5-million-Btu Intellihot water heaters fit into a 3-by-6-foot footprint, offering immense space savings compared with the previous boiler system.

“I’m always for reliability, especially with the hotels,” Castaldi says. “Getting parts on an island can be difficult, especially when they’re one-of-a-kind parts. Intellihot has modular tankless heaters inside the cabinet. Essentially, you pop it out, pop in a new one, and away we go. So it’s really easy to stock those modular heaters as replacements.”

Visit propane.com to learn more about tankless water heating and how the Intellihot installation will save the resort $90,000 annually for a three-year ROI.