Home Publisher's Point of View FSTC Study Uncovers Truth About Dishwashing Machine Performance

FSTC Study Uncovers Truth About Dishwashing Machine Performance

1494
0
SHARE
Glenn Hasek

As I have learned over the years I have been publishing Green Lodging News, the kitchen can be a hub for inefficiency. Leaky freezers, fans that don’t stop running, and wasted food are just a few examples. Of course the kitchen is also a place with plenty of potential for significant water waste. Where there is a faucet, there is waste just waiting to happen. This past week I posted an article about a study that was conducted by Pacific Gas and Electric Company Food Service Technology Center (FSTC). The study, entitled “Conveyor Dishwasher Performance Field Evaluation Report,” documents the energy and water savings and economic benefits of replacing an old inefficient dishwasher with a new efficient or best-in-class dishwasher. The study also highlights how dishwashers become less efficient over time and how many dishwashers (at any age) fail to operate to their design specifications. When was the last time you had your dish machines checked to see if they are operating as they should?

For the study, the folks at FSTC included performance data from 18 dishwashers. One of the testing sites was the Claremont Hotel, Club and Spa in Berkeley, Calif.

The normalized results from 18 sites showed roughly a 70 percent reduction in water and 55 percent reduction in energy use by replacing old conveyor dishwashers with new high-efficiency models. Specifically, the water use of the average conventional rack conveyor, at 691 gallons per hour of rinse operation, was reduced by 65 percent when replaced by an average high-efficiency unit, using 261 gallons per hour. Similarly, the energy use was reduced by roughly 55 percent. The water savings from flight conveyor dishwashers was even greater—representing a reduction of 75 percent. Water use of the average conventional rack conveyor, at 1,115 gallons per hour of rinse operation, was reduced to 267 gallons for the average high-efficiency unit. Similarly, the energy consumption was reduced by 55 percent. Impressive savings!

Less Water Equals Greater Savings

Old inefficient conveyor dishwashers were replaced with Energy Star qualified high-efficiency models at four sites. The average cost savings per site based on average California utility rates was approximately $22,000 per year. In each case, the cost savings were driven by the substantial reduction in water use.

For my article, I spoke with Amin Delagah, Research Engineer IV, Fisher-Nickel, Inc. (operator of FSTC). He told me, “Older machines do not have good diagnostics. A lot of these machines can become really inefficient. Malfunctions don’t get caught.”

On an average day, the flight conveyor at the Claremont Hotel, Club and Spa used 6,018 gallons of water. Tanks fills, for the most part, were not close to the manufacturer’s specifications. Daily water waste over the period ranged from zero to 4,916 gallons per day. The dishwasher averaged 4.9 tank fill and dump operations per day with an average fill of 477 gallons which is 3.5 times more than equipment specifications. Rinse water use was 8.6 gpm which is 50 percent over the manufacturer’s specifications at 5.6 gpm. There were other problems with the machine as well.

Studies of the dish washing machines at the Claremont Hotel, Club and Spa and the other sites demonstrated that model specifications, according to FSTC, “were a crude way to estimate real world water use.”

Don’t Go By Printed Specifications

The research showed that old conveyor dishwashers consume two to three times more water than was predicted based on the rated rinse flow and tank volume specifications. High-efficiency conveyor dishwashers used 70 percent to 85 percent more than the rated specifications.

In its research, FSTC found that facility operators oftentimes will perceive that the operating time of their machine is higher than it actually is, leading to the oversizing of new machines—again, more waste.

“A lot of these facilities don’t need the machines they are using,” Delagah says.

Inefficiencies found during FSTC research also emphasize the need for proper machine maintenance in order to eliminate water and energy waste. The study also found that oftentimes machines are not used properly. Placing back of house wares in machines not meant for them can lead to additional water waste.

The Importance of Submetering

Delagah says that to better document actual water and energy consumption, you should really be submetering your dish machines. “Technically, it is not very difficult to submeter,” he says. “It allows the facility to keep up to speed on the operation of the machine by identifying maintenance issues and when staff training is appropriate to get back to the benchmark operating parameters documented when the machine was commissioned.”

Alternatively, FSTC encourages the purchase of smart dishwashers that minimize water and energy use while having integrated water and energy meters and logging and communications hardware.

Be sure to read the FSTC study for additional suggestions on how to better monitor and operate rack and conveyor dishwashers. Also be sure to watch for an article here soon on the latest smart machines available from suppliers of rack and conveyor dishwashers.

Who is Your Sustainability Champion?

Green Lodging News is always looking to profile sustainability champions in our Personnel Profile section. If you would like to nominate someone for this section of Green Lodging News, contact me at (813) 510-3868, or by e-mail at editor@greenlodgingnews.com.

Looking for Guest Columnists

Every two weeks Green Lodging News posts a new guest column on its website. (Click here for examples.) The guest column also appears in the weekly e-newsletter. Green Lodging News is currently in need of industry experts to contribute occasional guest columns. Experts may include consultants, architects, designers, suppliers and those who own or operate green lodging establishments. Columns may be articles that take a stance on a particular subject or be strictly educational in nature. Columnists benefit by having their photo included along with a one paragraph description of their company. Interested in writing a column? Contact Glenn Hasek, publisher and editor, at (813) 510-3868, or by e-mail at editor@greenlodgingnews.com.

Planning Advertising for 2016?

Green Lodging News is accepting reservations for advertising spots for 2016. Many excellent spots are available on the website, in the weekly e-mail newsletter, and Green Lodging Survey. Many Green Supplier Spotlight dates are also available. Interested in receiving a 2016 media kit? Be sure to contact me as soon as possible at (813) 510-3868, or by e-mail at editor@greenlodgingnews.com. Media kits can also be accessed by clicking here. Thank you to all of those companies that consistently support Green Lodging News.

Newsletter & Green Supplier Spotlight Circulation

The circulation of our weekly e-newsletter and Green Supplier Spotlight currently stands at 4,978. Thank you to our new subscribers for signing up. Be sure to encourage your colleagues to do the same. There is a “subscribe” form in the upper left area of the Green Lodging News home page.

Green Lodging News & Social Media

Green Lodging News now has 1,709 Twitter followers. Thank you to all of those who follow our tweets. In addition to following us on Twitter, be sure to bookmark the Green Lodging News Blog in your browser. More importantly, participate with your comments. Green Lodging News is also on Facebook. Be sure to “Like” us there. Green Lodging News now has 790 Facebook followers.

As always, I can be reached at editor@greenlodgingnews.com.

LEAVE A REPLY