Warewashing plays a central role in any sustainable kitchen operation. It’s one of the few areas that operates continuously and consumes significant amounts of water, energy, and chemicals, so it sits near the very top of the list of priorities in operations that want to improve sustainability.
“Warewashing is probably the number-one place that can impact sustainability, as it uses so much energy, water and labor,” says Kip Serfozo FCSI, VP of design at Cini-Little. “It is also where the food waste is coming to and is handled, so any improvement in overall performance there would have a big impact.”
“If the warewashing area does not work then the kitchen falls over,” adds Mick Jary, specification director of Meiko UK.
“If the restaurant does not have clean utensils, pots, pans, crockery or glassware then there is no restaurant. We have to ensure that what we manufacture is the most efficient that we can put out sustainably, with ultimate ease of use on a small footprint.” Chief among concerns for consultants is energy, the cost of which has risen sharply. Water is a finite resource and must be managed carefully, as more parts of the world are facing scarcity in the years ahead.
“Ergonomics is important because finding kitchen porters is like finding hen’s teeth, so equipment must be easy to use and easy to train people on,” says Jary. “All food waste comes back to the dishwasher area, so that is where we manage it. And these areas are getting smaller and smaller, so we must make everything as compact and efficient as possible.”
Heeding the needs of operators
Many manufacturers have invested heavily in R&D and made significant improvements. For example, the pre-wash stage used to use clean water, but now many machines use water recycled from the end of the cycle to remove dirt from plates before the main wash. Dirty water is filtered and cascaded back to the start of the cycle.
On energy, the biggest step forward has been in the use of reclaimed heat. Warewashing equipment produces a lot of steam, which can be used to heat water for the next wash cycle, resulting in a significant reduction in energy use, costs and carbon emissions. Heat exchangers such as hoodmounted steam condensers can efficiently preheat cold water and reduce the burden on the main water heater.
“Heat recovery was a big step forward,” says Tarah Schroeder FCSI, managing principal and COO of Ricca Design Studios. “There has also been a lot of focus on addressing idle energy use and making machines smarter and easier to use. Going trayless could have an impact on food waste, and we’re looking at lower waster usage per rack too. Owners and operators in large institutional projects are also thinking about recruitment and retention, so they want to make it a more comfortable environment in which to work.”
Heat recovery can cut energy use by as much as 20% in some operations. Furthermore, newer machines are using small granules added to a high-pressure rinse to scrub plates with less hot water and shorter cycles, cutting water and energy use by a further 10-15%.
In many dishrooms, food waste is transported by pump or vacuum to a holding tank to go to anaerobic digestion, and there has not only been a concerted effort to reduce the amount of detergent that is required to achieve high standards of hygiene, but manufacturers are also working closely with chemical manufacturer partners to ensure that any chemicals that go to the drain are not harmful. “Warewashing is continuous, so it is a prime target for efficiency gains, and a lot has already been done with energy-efficient pumps and heat recovery,” says Vinoo André Mehera FCSI, CEO of promaFox.
“You are impacting energy gains, water use, chemicals with smart dosage – a lot of things that have negative connotations – so there are multiple wins.”
Foundations for the future
Manufacturers and consultants alike believe that the evolution of sustainability in warewashing will be led by AI and automation. Intelligent systems will help to monitor performance and will operate machines more efficiently.
“AI cameras can be introduced to check how dirty the plates are upon entry and pick the shortest safe cycle, then scan the tank water to decide exactly when to dump it – saving water, energy and chemicals without breaking hygiene rules,” says Vant Tan FCSI of CKP Hospitality Consultants.
According to a spokesperson for manufacturer Hobart, however, “the ultimate vision is ‘washing without water’,” a concept the company is now actively pursuing.
The vision focuses on drastically reducing water and energy consumption through integrated drying systems, more efficient cycles, and steam cleaning to pre-treat heavily soiled items. And while fully waterless washing remains a lofty goal, it shows the strong drive that manufacturers have to take the next big leap forward in sustainability.
Jim Banks
