Reblogging this from RIMAG.com


Green Operations: Tankless Water Heaters
In the right setting, tankless water heaters can offer water and energy savings on tap.
By Lisa Bertagnoli, Special to R&I -- Restaurants and Institutions, 10/1/2009


At Drago’s in Metairie, La., tankless water heaters provide super-hot water to the restaurant’s steam kettles, making them work more efficiently, says co-owner Tommy Cvitanovich.Drago’s, a 300-seat seafood restaurant in Metairie, La., used to get its hot water the conventional way—via a 150-gallon tank that heated and stored water. When co-owner Tommy Cvitanovich embarked on a $3 million renovation of the restaurant in 2004, he switched to tankless heaters.
With the old tank, Cvitanovich says, employees would get halfway through a night’s cleaning and then run out of hot water. The old tank also didn’t provide water at the proper temperature needed for multiple daily cleanings of the greasy char-grilling station. Drago’s new tankless water heaters are more efficient at supplying adequate hot water to meet all of the restaurant’s demands.

As their name suggests, tankless (or on-demand) heaters don’t store hot water. Instead, when the hot-water tap is turned on, cold water from the utility enters the heaters through an inlet valve. As water passes through the unit, it is warmed via heating elements, and then exits to the point of hot-water use, be it a hand-washing sink or steam-jacketed kettle. Conventional hot-water tanks heat and store water; when the hot-water faucet is turned on, hot water runs from the tank to the point of use.

Tankless water heaters have several advantages over traditional models: Tankless units save energy—and thus money—and their use can earn points for operators working toward becoming certified by the U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED) program. They save space, too.

Light on Energy
Energy savings may be the most compelling reason to choose a tankless heater over a traditional one. Although high-efficiency tank models are available, conventional heaters generally consume lots of energy keeping stored water hot. Hot-water heating can account for 20 percent to 25 percent of a restaurant’s total energy bill, says Sam Khalilieh, senior vice president of engineering services at WD Partners, a Columbus, Ohio-based foodservice design firm. With tankless heaters, “you only heat what you need—no more, no less,” Khalilieh says.

There is a caveat: Tankless heaters cost considerably more to purchase and install than traditional heaters. The energy savings allow for a return on investment, on average, of two to three years, Khalilieh says.

Tankless units also can save water: Because hot water is delivered to the source of use instantly and at the right temperature, there’s no need to run the tap for a minute or two to heat the water to the appropriate temperature.

Space Savers
Unlike conventional water heaters, tankless models don’t take up valuable floor space. The units, which measure approximately 3 feet high, 18 to 20 inches wide and 10 to 12 inches deep, can be wall-mounted high off the floor or installed on a roof. And electric models are self-venting, meaning that the unit has its own air intake and exhaust vents (tankless gas heaters must be vented to the outside).


Einstein Noah Restaurant Group installed tankless heaters in five of its smaller units to save space. A desire for space savings was the reason behind Einstein Noah Restaurant Group’s decision to replace conventional hot-water heaters with tankless versions in five of its Einstein Bros. Bagels units. The company, which operates more than 400 bakery-cafes nationwide, installed the tankless heaters in its smaller stores that have about 1,700 to 2,200 square feet of total space.
“We are mainly using them in remodels and in places where we have very small back-of-the-house situations,” says Joshua Miller, construction manager for the Lakewood, Colo.-based chain. “Being able to hang them on the wall up high saves room.”

Miller says that the company will continue to install tankless heaters as traditional models in other units “reach the end of their life.” However, Miller still specifies high-efficiency, conventional hot-water tanks in new-construction units—a practice that he expects will change when energy-saving and return-on-investment figures for the tankless heaters materialize. (The heaters, installed earlier this year, haven’t been in use long enough to gauge their economic efficiency, Miller says.)

Tankless in Action
To provide hot water for two dishwashers, four steam-jacketed kettles, 12 bathroom sinks, and kitchen hand-washing and utility sinks at Drago’s, Cvitanovich has three tankless heaters, each the size of a suitcase, installed on the restaurant’s roof, saving interior space as well as venting costs.

Drago’s has used its tankless heaters for five years, and even though Cvitanovich does not formally track their energy use, he is satisfied with his decision. “Our gas bill is a couple of thousand dollars a month, but common sense says we’re saving energy,” he says.

Computer controls let staff set the water temperature, allowing the steam-jacketed kettles to work more efficiently. “You get the super-heated water, and you don’t have to wait as long for water to come to boil in the kettles,” Cvitanovich says.

He estimates his return on investment at about three years for the hot-water system and plans to install tankless heaters in his new restaurant, expected to open next year in Baton Rouge. He’s such a believer in the heaters that he also has installed them in his residence. “I have four kids,” Cvitanovich says. “I don’t want to take a cold shower.”

Contact writer at riedit@reedbusiness.com