By David Zabrowski and Richard Young
Frontier Energy/Food Service Technology Center (FSTC)
With everything that goes into running a restaurant, kitchen energy can dwarf the energy consumed by other building systems—often consuming five to 10 times the energy use per square foot. The energy use intensity (EUI) for the average office building is about 90,000 Btu/ft² per year, only a fraction of the 800,000 Btu/ft² used by the typical commercial kitchen annually.
With diverse processes such as cooking, refrigeration, warewashing, and ventilation driving much of the activity in the space, a commercial kitchen is essentially a miniature factory hidden inside a building. And, like many manufacturing plants, foodservice operators are looking for ways to boost their energy efficiency to lower costs and conserve resources. As such, many are looking to LEED standards as a solution for their energy goals.
The first version of LEED was created in 1998—not very long ago for an international standard—and was originally designed for office buildings. In the early versions of LEED, energy credits focused on regulating building loads, such as lighting, water heating, and space conditioning. Operation-specific loads, such as cooking, warming, refrigeration, and sanitation were considered “process loads” and largely ignored, though they can represent up to two-thirds of the energy used in a building.
To receive LEED certification, building projects must satisfy prerequisites and earn points to achieve different levels of certification. Prerequisites and credits differ for each rating system and teams choose the best fit for their project. Eventually, in the third version of the LEED standard, the energy and atmosphere credits included the appliances used in the space, but these were largely overshadowed by advancements in building shell technology, window glazing, rooftop conditioning units, lighting controls and building energy management systems. In fact, in the prescriptive version of the current LEED for Interior Design and Construction (ID+C) energy credit, only two of 16 available energy points are related to the equipment and appliances used in the space. Adding the equipment to a building energy model, can get you up to 25 points.
Over time, the U.S. Green Building Council (USGBC), which sets LEED standards, developed different specification guidelines for schools, healthcare, retail, and commercial interiors. The LEED website (www.usgbc.org/credits) lists all the different types of available credits along with recommended prescriptive measures and modeling baselines.
As LEED specifications became more established, USGBC began raising the bar by adding credits for adopting ENERGY STAR® appliances such as TVs, computer monitors and printers. USGBC also started working with various experts who assisted in the development of stricter standards for each building type, which led to some confusion. For example, LEED for Schools included different appliance requirements than LEED for Retail. The newest LEED Standard, Version 4, is much simpler. It unifies the disparate specifications from previous versions and focuses the energy credit on overall energy use reduction, which now includes all the process loads.
ENERGY STAR is Good for LEED Projects
LEED V4 states that, “Unregulated loads should be modeled accurately to reflect the actual expected energy consumption of the building. If unregulated loads are not identical to both the baseline and the proposed building, the simulation program may not accurately model the savings…” The standard continues to state that “process loads for retail may include refrigeration equipment, cooking and food preparation…and other appliances” and that these loads should be included in the energy reduction target for the project.
While this prospect can seem daunting, there is good news. LEED offers a prescriptive path that includes ENERGY STAR appliances under the ID+C specification. A possible two points are offered for specifying ENERGY STAR-eligible products. The ENERGY STAR program for commercial foodservice (www.energystar.gov/cfs) provides a simple path to energy savings for many major appliances, including refrigeration, ice making, cooking, warming and dishwashing equipment. The prescriptive path requires an easily achievable minimum of 90 percent, by rated power (kW or Btu/h), to qualify for both of the available appliance energy points.
This brings us back to the energy intensity of commercial foodservice equipment. When equipment is compared by a power (or BTU) rating, a single piece of cooking equipment—such as a fryer—can completely overshadow the impact of other appliances. To put it into perspective, a desktop computer is rated at about 100 watts. A standard deep fat fryer can be rated at 120,000 Btu/h, which equates to 35,000 watts or 350 times more energy than a computer. This makes it critical to hold to the ENERGY STAR specification and not allow less-efficient, lower-cost substitutions. A single non-ENERGY STAR fryer can blow up a whole ID+C LEED project because the criteria says you must have a minimum of 50 percent ENERGY STAR appliances as a prerequisite to even participate in the program. The smartest and easiest move is to simply specify 100 percent ENERGY STAR eligible appliances and be ahead of the game.
The high-energy efficiency of ENERGY STAR equipment makes them attractive to operators, which is why Tanja Crk, product manager for the ENERGY STAR Labeling Branch, says that ENERGY STAR also can be good for business. The ENERGY STAR program encourages distributors to become retail partners (www.energystar.gov/index.cfm?c=manuf_res.pt_retailer) and join the “Where to Buy List” (www.energystar.gov/commercial-food-service-dealer-locator), a new tool for end users to locate equipment dealers who sell ENERGY STAR commercial kitchen equipment in their area by zip code. The “Where to Buy List” includes storefront(s), contact information, and websites (including multiple locations, if applicable).
Modeling for Success
While the prescriptive path is straightforward, it does not provide much room for flexibility. An alternate path is to model the process energy loads for baseline and specified equipment. The LEED standard includes an appendix with energy usage specifications for generic baseline and efficient foodservice equipment (www.usgbc.org/node/4335155?return=/credits) that can be input into a daily energy consumption model for different appliances. The energy consumption metrics are based on standardized performance test methods published by the American Society for Testing and Materials (ASTM).
The ASTM F26 Committee on Food Service Equipment (www.astm.org/COMMITTEE/F26.htm) defines energy performance under standard operating conditions—preheating, idle (standby) and cooking—that can be used to compare the energy and production performance of equipment. Results from ASTM standard tests provide the foundation for ENERGY STAR, utility incentive programs, and equipment performance comparisons. The test methods also contain a daily energy model that accounts for the energy consumed in different operating states during a typical day. The model provides a result similar to the information contained in the yellow Energy-Guide labels (www.energy.gov/energysaver/appliances-and-electronics/shopping-appliances) on domestic appliances.
While the industry has not reached the point of pasting the daily energy use on appliances (or on the spec sheets), there are simple calculation tools available from California utilities (https://caenergywise.com/calculators/) and ENERGY STAR that can be used to support the appliance energy consumption models for commercial foodservice projects.
Communicating with the LEED Project Architect
Properly implementing LEED standards into a building requires a team of people from different disciplines to work toward a common goal. The approach for this collaboration depends on the project type. Building Design and Construction (BD+C) includes the building shell and everything in and around the building project, from internal loads to landscaping. Interior design and construction focuses on the interior construction within an already existing building shell. Regardless of the LEED project type, all building energy loads must be included in the building energy model, including all the foodservice equipment, refrigeration, and kitchen ventilation systems. This is an important fact that is often overlooked by the building architects and engineers.
Architects often draw a square on the plans and write the word kitchen on it, a one-size-fits-all approach that is not realistic. As all professional foodservice designers are aware, there is no such thing as a generic kitchen. For LEED projects, it is critical to establish a rapport with the project owner and architect from the beginning. The design of the kitchen space could dictate what energy efficiency measures are available for consideration. It is also important to note that kitchens can be very challenging to model, particularly with respect to commercial kitchen ventilation (CKV) loads. This is where it can be beneficial to work with an expert who has experience modeling commercial kitchens. Experienced modelers know how to balance heating and cooling loads in different spaces to account for all the energy loads in the space.
Conversely, when the foodservice designer is brought into a project too late (after 50 percent of the design has been completed), it significantly restricts the ability to influence the high-energy consumption of a commercial kitchen operation and places designers in a difficult position. A real-world example of this played out in a LEED certified university student center and dining hall. The architects and engineers designed and built the building as a generic box without communicating with the foodservice consultant or dining services operators, who had outfitted the generic kitchen on the plans with some heavy-duty cooking equipment. When the kitchen opened, chefs discovered that the ventilation, built according to LEED design, was insufficient to accommodate the smoke and heat from the cooking equipment. It was costly to upgrade the ventilation system and generated a lot of headaches for all the players, including the unhappy chefs dealing with a hot, smoky kitchen. One early design meeting between the mechanical engineers and foodservice consultants and operators could have found and fixed this issue.
As important as it is to involve the foodservice consultant at the start of a project, it is equally important to have the foodservice director on the design/planning team. The equipment in an institutional kitchen is expected to last a long time and drives the menu, the labor needed, and impacts operating costs many times more than maintenance costs and performance and utility costs over the lifespan of the equipment. A much better approach is to spend a little more up front to have a robust, flexible, efficient kitchen that is appropriate to the concept.
What about the Materials Requirement?
LEED V4 includes requirements for disclosing the source of raw materials, ingredients and environmental declarations. This has frequently been interpreted to apply to all the equipment and fixtures in a LEED building design, leading to varied requests for foodservice equipment manufacturers to provide sustainability declarations for the equipment in a project. Over the years, those requests have ranged from the recycled content of source materials, such as stainless steel, copper, and aluminum, to the amount of renewable content in the product packaging. These requests became so ubiquitous that NAFEM stepped in and developed a sustainability calculator (www.nafem.org/resources/nafem-sustainability-calculator/) to provide a consistent framework to measure and report the environmental impact of foodservice equipment, and to help clarify environmental factors that allow product comparisons and provide data that may be used in sustainability projects. “The calculator itself has great value, not just as a reporting format but as a way to consider all of the elements related to the use of CFS Equipment,” says Charlie Souhrada, CFSP, vice president of regulatory affairs for NAFEM.
While the NAFEM Sustainability Calculator was a step toward uniformity for a widely varied industry, its results do not always apply to LEED projects. Manufacturers are sometimes asked by LEED project teams for materials data similar to what the NAFEM calculator can produce but this information is not necessary for LEED certification, and it will not gain any project points under the Materials Requirement (MR) credit. According to Stefanie Young of the USGBC, “project teams may only include materials permanently installed in the project in the [Materials Requirement] calculations. Mechanical, electrical, and plumbing components and specialty items such as equipment cannot be included. Furniture is the only exception if it is included consistently in the submission.”
Permanently installed building products is defined by LEED as structure and enclosure elements, installed finishes, framing, interior walls, cabinets and casework, doors, and roofs. In other words, foodservice equipment is judged solely on energy and water use and not on the component materials.
Becoming a LEEDing Foodservice Designer
A common question asked is, “With all of the equipment options available and different marketing claims, where can we find unbiased information on equipment performance?” ENERGY STAR provides a simple straightforward path to identifying energy-efficient equipment. The lists of rebate-qualified equipment from the California utilities (https://caenergywise.com/rebates/) is another great resource. Both programs not only list the make and model of the qualifying equipment, but also list the energy ratings that serve as the basis for qualification. This allows designers to select and compare equipment to identify the most efficient options for a LEED design.
Now that all the kitchen energy loads must be considered in the building model under LEED V4, it is more important than ever to consider energy-efficient foodservice equipment. This is an excellent opportunity for experienced foodservice designers to add value to a LEED project. The green building world is on fire with new ideas, better materials, and inspired designers. It’s time to add commercial foodservice energy efficiency.