Improving Energy Efficiency in Commercial Kitchens

Commercial kitchens—such as those found in full-service and quick-service restaurants, hotels, and hospitals—are intense energy users, consuming as much as three times more energy per square foot than most other types of commercial buildings. Fortunately, it’s easy and doesn’t cost much to keep commercial kitchen equipment clean and make simple operational changes that can reduce energy use by as much as 10 to 30 percent while achieving additional non-energy benefits, including improved operating performance and increased kitchen staff comfort.

In a typical foodservice facility, food preparation, refrigeration, and water heating combined represent nearly 60 percent of total energy use, making those systems excellent targets for energy savings (Figure 1).

Figure 1: Energy consumption by end use
Refrigeration, lighting, and cooling dominate electricity use; cooking, water heating, and space heating are responsible for the vast majority of gas use.
Efficiency improvements through maintenance
this section

Effective maintenance is essential to help keep equipment running properly, but it can also often help improve energy efficiency as well. These suggestions focus on different energy uses, and they offer simple strategies for turning things off, keeping things clean, and verifying that proper settings are used in order to minimize energy waste.

Food preparation

Kitchen equipment such as ovens, fryers, broilers, and burners all require energy to function. By making sure that equipment is in good working order and used only when needed, facilities managers can significantly reduce energy use in the kitchen at no cost.

Turn off unused equipment. Running equipment that’s not in use wastes a significant amount of energy in commercial kitchens every year (Table 1). Not only does the equipment itself tend to be inefficient, but it often turned on as soon as the workday commences, and it remains on until long after the last meal has been prepared.

Table 1: Turning off unused equipment saves energy
Kitchen equipment, including gas and electric burners, gas underfired broilers, and electric broilers, can waste large amounts of energy if left on when they aren’t being used.

Check oven and steamer seals. To keep heat from escaping, it’s important to make sure the seals around oven and steamer doors are in good shape and create a proper seal—if not, you may need to replace them.

Keep equipment clean. Cleaning equipment can help it operate more efficiently and extend its life. For example, sediment in the bottom of a fryer can reduce its efficiency, and debris at the bottom of an oven can prevent the door from sealing well.

Refrigeration

Almost every commercial kitchen has at least one refrigerator and freezer, and this equipment typically represents a significant source of energy consumption.

Inspect refrigerator and freezer doors. To prevent leakage of cool air, replace worn gaskets and make sure doors are aligned properly. Also check that automatic door closers are functioning and strip curtains are not damaged.

Clean refrigerator coils regularly. Cleaning dirty air-conditioning and refrigeration (evaporator and condenser) coils can improve efficiency and help prevent early compressor failure.

Water heating

Commercial kitchen staff have to do a lot of cleaning, and hot water— and therefore the hot water heater—is an essential element of getting it done. Fortunately, there are several straightforward ways to minimize energy impacts of hot water use.

Use proper water heater settings and ensure that the distribution system is leak-free. Set the water heater temperature to 140° Fahrenheit (F) (60° Celsius [C]), insulate hot water lines, regularly ensure that the water heater temperature/pressure-relief valve is operational, and fix any leaks.

Use proper dishwasher setpoints and operation mode. Set rinse pressure to 15 to 25 pounds per square inch (100 to 172 kilopascals) to avoid excess water use, set the wash-tank temperature to 160°F (71°C—high enough to sterilize), and set the booster heater setpoint to 180°F (83°C) (in accordance with guidelines from NSF International, an organization that develops standards for public health and safety). Check that wash curtains for conveyor washers are not missing or too short to prevent heat from escaping. Also, run the dishwasher only when full, don’t run it in manual mode—the machine will likely run too long without automatic shutoffs—and turn off high-temperature dishwashers at night so that their heating elements will not consume energy.

Investigate your sprayers. Prerinse sprayers are used to remove food from dishes before they are placed in a dishwasher. Although a national standard mandates that all prerinse sprayers manufactured after 2006 be limited to a flow rate of 1.6 gallons per minute (gpm), many currently installed sprayers use up to 5.0 gpm, according to the U.S. Department of Energy. Part of the problem is that these sprayers tend to wear out over time, so even low-flow sprayers may ultimately end up being very inefficient. In areas where these inefficient sprayers are used, upgrading to low-flow sprayers can conserve water while also reducing the energy needed to maintain the supply of hot water. An easy way to tell whether you should replace your sprayer is to use it to fill up a 1-gallon water pail—if it takes less than about 30 seconds, it’s a good idea to replace it. Given the small initial cost of low-flow valves (around $60 per valve), this measure typically yields a simple payback period of less than two months.

General best practices
this section

In addition to the technology-specific measures for reducing energy use described above, there are several overarching strategies that can also help.

Create a maintenance calendar. Using a calendar to keep track of all the recommended maintenance dates for parts and equipment—including monthly, quarterly, semiannual, and annual checks—will help to achieve maintenance goals. The calendar should include dates for calibrating thermostats on cooking and air-conditioning equipment, for lubricating exhaust- and supply-fan bearings, and for changing air-conditioning equipment air filters.

Hire a maintenance technician. A maintenance technician—or a consultant who specializes in maintaining food-service equipment—can ensure that a facility follows its maintenance schedule and properly maintains complex equipment.

Educate staff. An inexpensive way to save energy is to simply help your staff be conscious about energy use. Develop simple energy management procedures—with checklists—and assign responsibility to specific personnel on each shift for turning off cooking equipment, exhaust fans, lights, computers, and other office equipment.

E Source Business Energy Advisor

Your one-stop source for actionable advice on proven business energy management strategies. The E Source Business Energy Advisor (BEA) is a library of information that integrates with your existing website and provides sector-specific energy advice for a wide variety of business types and technologies. By providing this valuable information on your website, you can improve engagement with your business customers, help them make the case for energy efficiency, and drive them to your efficiency programs. BEA also serves as a valuable resource for account managers, business contact center representatives, and demand-side management program managers.