City of Roseville

Average energy-use data

Figure 1: Energy consumption by end use

National data shows that in hotels and motels, the primary consumers of electricity are office equipment, ventilation, and lighting and water heating is the main consumer of natural gas.

In order to better manage your building’s energy costs, it helps to understand how you’re charged for energy. Most utilities charge commercial buildings for natural gas based on the amount of energy delivered. Electricity, on the other hand, can be charged based on two measures: consumption and demand (figure 2). The consumption component of the bill is based on the amount of electricity (in kWh) that the building consumes during a month. The demand component is the peak demand (in kilowatts) occurring within the month or, for some utilities, during the previous 12 months. Demand charges can range from a few dollars per kilowatt-month to more than $20 per kilowatt-month.

Figure 2: Diagram of a hypothetical daily load shape

Over 24 hours, the highest power loads for US hotels and motels are interior lighting and HVAC, with spikes occurring in cooking and exterior lighting.

Because it can be a considerable percentage of your bill, you should take care to reduce peak demand whenever possible. As you read our energy cost-management recommendations, keep in mind how each one will affect both your consumption and your demand.

Quick fixes

Longer-term solutions

Although the actions covered in this section require more extensive implementation—such as automating HVAC shutoffs—they can dramatically increase the efficiency of your facility without compromising the hospitality environment. Ask your utility representative for more information about starting any of the following projects.

Commissioning

Commissioning is a process during which engineers observe a building and perform a tune-up to ensure that its systems are operating efficiently and as intended. Commissioning takes place when a facility is first built; however, if a building has never been commissioned, it’s ripe for retrocommissioning (a similar tune-up on an existing building). All buildings also stand to benefit from regular recommissioning, which can take place periodically throughout a building’s life.

Studies have shown that commissioning can save a typical 100,000-ft2 hotel 10% to 15% of its energy costs, or roughly $20,000 per year. Savings typically result from resetting existing controls to reduce HVAC waste while maintaining or even increasing comfort levels for occupants. You should recommission your facility every three to five years, depending on changes in the facility’s use, the quality and schedule of preventive maintenance activities, and the frequency of operational problems. You should also schedule commissioning after major remodels or additions.

Lighting

You can use many different light sources to provide efficient lighting throughout your hotel or motel operations. LEDs are a potential solution that you can apply throughout your facility. Though not yet cost-effective in all cases, LED technology is worthy of consideration for any lighting application.

Room-based automation

Occupancy-based controls (OBC) provide a wide variety of applications for hotel guest rooms. Both HVAC and lighting are controllable on a room-by-room basis because all of the controls they use are local to the room and don’t depend on connecting to a whole-building automation system.

Whole-building automation

Since larger hotels have more common space―such as conference rooms, offices, and restaurants―these facilities can use general-purpose building automation systems (BASs) to control HVAC and lighting. If you have a BAS or are planning to add one in new construction, you can more easily implement the following measures.

Water heating

Water heating is a major load for hotels and motels, accounting for a third or more of a facility’s energy consumption. Commercial heat-pump water heaters (HPWHs) are two to four times more efficient than conventional water heaters and also provide space-cooling capacity. In fact, they can cut water-heating costs up to 50%. However, before deciding to use an HPWH, it’s important to do a careful economic analysis—they’re more expensive than conventional water heaters, and their performance varies with climate.

Direct-vent, sealed-combustion condensing water heaters and boilers with efficiencies higher than 90% are the next-most efficient option. Unlike traditional water heaters, condensing boilers operate very efficiently during periods of low water demand, and they can also provide space heating. Installing multiple smaller water heaters provides better reliability, effectiveness, and efficiency compared to using one large water heater.

Hotels and motels can also use HVAC, shower, laundry room, or kitchen heat-recovery systems to cut hot-water expenditures. You can get “free” hot water from cooling and refrigeration equipment by using double-bundled heat exchangers in the chillers or a plate heat exchanger in the condenser-cooling loop. When you use drainwater heat-recovery equipment, you can save 50% to 60% of water-heating energy with a payback period ranging from two to seven years. It can also double or triple the first-hour capacity of water heaters. Learn more about the technology on the U.S. Department of Energy’s (DOE’s) Drain-Water Heat Recovery page. In addition, installing a variable-frequency drive (VFD) and controls on the hot-water pumping systems will reduce pumping energy during periods of low use.

In the hotel kitchen, low-flow prerinse spray valves are one of the easiest and most cost-effective energy-saving measures available. These devices use a spray of water to remove food waste from dishes prior to cleaning in a dishwasher. They reduce water consumption, water-heating energy, and sewer charges. Look for models with a flow rate of 1.6 gallons per minute or less.

You have several options for hotel laundry operations. Efficient tunnel washers can reduce costs through labor and utility savings. A few manufacturers are using new alternative technologies to save energy. For example, ozone and polymer bead laundering systems offer big savings by using cooler and much less water; they also use less energy and detergent. And carbon dioxide (CO2) laundry technology is completely waterless and eliminates the need for drying, yielding significant savings. At this time, CO2 laundering is only offered as a third-party service, and only on a cost-per-pound-of-laundry basis, but you should consider it if you contract out your laundry service.

For hotel swimming pools, indoor pool covers typically yield paybacks of one year. Covers for heated outdoor pools and hot tubs may yield even better savings. Indoor pools require simultaneous heating and dehumidification, and HPWHs can efficiently serve both of these needs: they heat water while producing cool, dehumidified air for the room housing the pool. Using an HPWH can reduce heating costs for gas- and electricity-heated pools as much as 40% and 80%, respectively.

Low-temperature unglazed solar water heaters are an inexpensive approach that’s well-suited to swimming pools and spas in warmer climates. Glazed flat-plate collectors can provide higher-temperature water. Also, although we haven’t yet seen any substantial research confirming energy savings, it’s likely that variable-speed pumps and controls can save energy in certain swimming pool applications. For example, if the local requirements around flow rates are lower than those currently being used by the pool in question, variable-speed pumps could offer significant opportunities for energy savings.

Building envelope

Awnings, overhangs, and windows with a low solar heat gain coefficient (how much solar radiation comes through) help reduce the amount of solar heat that comes in while still allowing daylight through. Strategically planted shade trees can also reduce solar heat gain in buildings. Cool roofs, which often include light-colored roofing materials, not only reduce cooling energy consumption by 25% to 65% during the summer but also extend roof life. Green roofs—planted with grass and other vegetation—provide excellent insulating properties, prolong roof life, reduce stormwater runoff, and offer an aesthetic appeal that could be valuable to your hotel or motel property. However, green roofs are expensive and haven’t proved to be cost-effective.

Retrofitting with new, high-performance windows can be prohibitively expensive. Installing reflective film inside existing windows can be a more cost-effective option for reducing solar heat gain while still admitting useful visible light, resulting in payback periods of less than three years. Other window coverings such as shutters, shades, and draperies provide insulation benefits, especially in summer months, when they reduce the amount of sunlight and heat entering rooms.

For lobby areas, revolving doors are the best choice for keeping wind and weather out. The National Renewable Energy Laboratory explains in its Commercial Building Envelope Checklist (PDF) that revolving doors can drastically reduce the amount of unconditioned air entering the building compared to standard doors. Check these doors periodically to ensure that there are no leaks along their edges or bottoms.

HVAC

Vending and food storage

Energy-efficient equipment

A simple way to ensure that equipment is energy efficient is for your purchasing departments or franchisees to specify products that are certified by Energy Star. Energy Star–qualified products relevant to hotels and motels include equipment such as:

• Commercial refrigerators and freezers
• Televisions, DVD players, and audio equipment
• Computers, monitors, and printers
• Commercial fryers and commercial steam cookers
• Fax machines, mailing machines, scanners, and copiers
• Vending machines

In addition, the DOE’s recommendations for Energy-Efficient Products and Energy-Saving Technologies from its Federal Energy Management Program may be appropriate for items not covered under the Energy Star program.