Grocery
As a store owner or manager, you handle inventory, make sure the food deliveries are on time and keep the shelves are well-stocked. You manage a labor force, assign shifts and keep employees content. In short, you manage a complex operation. Hawaii Energy wants to help you manage energy as well.
Figures are based on Hawaiian Electric Company data and an average electric consumption of 76 kWh/square-foot-year. Energy use is affected by weather; number of occupants; building size and thermal integrity; cooling, heating, and water systems; and miscellaneous equipment.
Energy Management Program
An energy management program studies energy usage, how and where energy is used, and evaluates ways to save, reduce and implement energy conservation measures to increase operating efficiency. It can also involve training employees on energy-saving practices.
Some areas to consider in an energy management program include:
Heating, Ventilating, Air Conditioning (HVAC)
Shoppers generally prefer temperatures between 65°F and 75°F. Heating, cooling and humidity control for grocery stores is designed to provide a comfortable environment for shoppers and to permit refrigeration cases to operate efficiently.
Here are some ways to save energy on HVAC systems:
- Installing energy efficient air conditioning/chiller equipment. Rebate qualified.
- Installing HVAC fans and pumps with variable frequency drives that can control motor and pump speeds as well as the electricity needed to run the fans and pumps. Rebates for both fans & pumps.
- Applying window film to reduce heat loss. Rebate qualified.
- Adding insulation for windows and doors, such as weather stripping and thresholds.
- Installing a timer on supply air fans.
- Utilizing energy management systems.
- Decreasing the daytime thermostat setting.
- Installing a night setback procedure.
- Installing an economizer.
Energy conservation measures vary with each individual system and must be looked at by someone qualified in HVAC and controls.
Lighting
Lighting, usually designed to highlight the merchandise, can make up 20% of your energy bill. Fluorescent tubes, generally used in most stores, are a relatively efficient lighting source.
Hawaii Energy has a number of rebates that can help store lighting become even more energy efficient:
- Low-wattage T8 and T5 lamps with electronic ballasts can replace older, less efficient T12s. Rebate qualified.
- Reflectors enable delamping (reducing the number of lamps needed). Rebate qualified.
- CFLs use 75% less energy and last 10 times longer than incandescent bulbs. Rebate qualified.
- LED exit signs are even more efficient that fluorescent lights. Rebate qualified.
- Induction lighting offers long-lasting, low-maintenance solutions to hard-to-reach places and public facilities. Rebate qualified.
- Pulse-start metal halide and high-pressure sodium lamps provide high-intensity lighting, long lamp light and high energy efficiency for spaces where lights are used for many hours and have high ceilings. Rebate qualified.
- Occupancy sensors, or automatic lighting controls, switch off lights when people leave the room and turn them back on when people return. Programmable timers can also turn lights on and off at appropriate hours. Rebate qualified.
- Light tubes and other natural light maximizers that can replace some electric lighting can qualify for Hawaii Energy custom rebates. Rebate qualified.
Refrigeration
The refrigeration system typically uses 45% or more of your total electricity use to run the compressor, fan motors, condensers and evaporators, and for heat to defrost case coils. Your energy management program should concentrate on this major energy user.
Energy conservation measures to refrigeration equipment might include:
- Reducing refrigeration case temperatures to meet but not exceed code requirements.
- Turning off medium-temperature case lights at night.
- Cycling anti-sweat heaters on low-temperature glass doors.
- Installing glass doors over open display refrigeration cases.
- Installing plastic-strip curtains on walk-in coolers and freezers.
Water Heating
Hot water in grocery stores is used for cleaning counters in meat cutting areas, bakeries, and general store cleanup. Water heaters which supply meat cutting areas are generally set to 155°F in order to meet sanitation requirements. Energy conservation measures implemented to the water heating system might include insulating the pipe and water heater tank or installing a compressor heat recovery system to preheat the water supply.
Miscellaneous
A small part of the energy used by a grocery store is related to miscellaneous equipment, such as cash registers and cleaning systems. This equipment should be operated only when necessary and maintained to ensure proper operation.
