Retail stores are where we buy our clothes, devices, art, and other goods and services. Retail stores are known for their spotlighting to attract a shopper’s eye and attention. As a result, lighting makes up 35% of the energy consumption in a retail building. Heating, ventilation, and air conditioning (HVAC) makes up 48% – together contributing over 80% of total energy needs.
Most Canadian and U.S. retail buildings were built before 1980. In most cases, retail buildings can achieve a 10-20% reduction in energy use from regularly scheduled operations and maintenance (O&M). No-cost and low-cost measures for retail buildings are outlined in the following table.
Table 1: No-cost and low-cost energy and water conservation measures for retail buildings
|Measure Type||Measure Name||Measure Description|
|Envelope||Replace damaged door weatherstripping||Especially on exterior doors, make sure that damaged weatherstripping is replaced and drafts are eliminated.|
|Lighting||Exterior light scheduling using photocell sensors||Use a photocell sensor to turn exterior building lights on and off 30 to 60 minutes after sunset and before sunrise, respectively. Photocells detect sunrise and sunset accurately making them more energy-efficient than clock-based timers that may lose sync with night and daytime over the course of a year, resulting in unnecessary lighting.|
|Lighting||Install LEDs in exit signs||Since they run 24/7, install LEDs in exit signs to maximize their efficiency.|
|HVAC||Clean heating and cooling coils||In the air handling unit (AHU), clean the heating and cooling exchanger’s coils and fins to maximize efficiency.|
|Envelope||Eliminate Leakage||Use an infrared camera to identify and remedy building energy leak points. As-built drawings can also help in the leakage identification process.|
|HVAC||Replace filters at the optimal schedule||Filters should be replaced regularly, and the pressure drop in the air handling unit (AHU) measured after replacement, and continuously. Too large a pressure drop caused by a dirty or improper filter can lead to inefficient processing of the air, leading to unnecessary energy usage. It can also accelerate the filter’s end-of-life.|
|HVAC||Temperature based HVAC lockouts to rooftop unit (RTU)||Heating and cooling should not occur when the outdoor temperature is suitable for use in the building. Adding a temperature-based lockout to the RTU’s heating and cooling sections can ensure there is no redundant mechanical heating or cooling.|
|HVAC||Eliminate unneeded HVAC processes during unoccupied periods||If the HVAC can be turned off during unoccupied periods, do it! Outside air dampers should be closed as well.
Reducing runtime is one biggest “bang for your buck” opportunities to increase efficiency and reduce cost.
|HVAC||Close outside air damper during unoccupied periods||When the building is vacant, air dampers that control building ventilation can be closed to prevent any unnecessary heating and cooling on ventilated air. Ventilation adjustments should follow building best practices for maintaining air quality during Covid-19.|
|HVAC||Correct refrigerant charge||In refrigerant-reliant heating and cooling systems, ensure the refrigerant charge level is at optimal levels.|
|HVAC||Adopt a regular HVAC schedule||HVAC systems should be inspected and adjusted twice a year to ensure proper functioning. In cold climates, this can be done before the winter and summer seasons.|
|Education / Training||Employee education and training||This measure involves energy and water conservation awareness and training for employees and shoppers. Empowering and engaging employees can go a long way in your efficiency improvement goals.|
For deeper savings in retail buildings, a lighting redesign based on current, affordable technology can reduce overall wattage per square foot (W/sq.ft) and energy use. Energy savings from a deep lighting retrofit can exceed 20%. Updating rooftop HVAC units (RTUs) at system end-of-life with the latest models can also be considered to improve building efficiency. Here is a fulsome list of deeper retrofit measures for retail buildings.
Table 2: Deeper energy and water conservation measures for retail buildings
|Measure Type||Measure Name||Measure Description|
|Lighting||Interior lighting retrofit||There are different levels of lighting retrofits. A simple lighting retrofit involves light and ballast replacement with the latest LED technology. A deeper lighting retrofit is a broader lighting redesign that can include LPD and light placement optimization, daylight harvesting, and sensor controls.
Common areas and offices can be a good starting point. When access permits, in-suite lighting upgrades can be considered.
Tunable white LED systems could be considered as new findings on their non-energy benefits, including positive health impact, emerge.
|Lighting||Install occupancy sensors||Install occupancy sensors in transient areas such as lunchrooms and changing rooms to turn lights off when vacant. This reduces energy waste from “day-burning” lights that could be intentionally or accidentally left on.|
|Lighting||Add daylight harvesting||Implement daylight harvesting to leverage natural light. When daylight is sufficient to offset indoor lights, these indoor lights turn off automatically. This measure can be considered on its own or as part of a lighting retrofit.|
|Lighting||Exterior Lighting Retrofit||Retrofitting exterior lights with newer, efficient lighting technology can have a meaningful impact on electricity usage.|
|Plug Load||Add office equipment on/off controls||Add computer energy management software and use smart power strips to automatically turn off electronic equipment (computers, lights, etc.) when not in use.|
|Plug Load||Purchase energy-efficient appliances and equipment||Replace aging or end-of-life lunch room appliances and computer equipment with rated energy efficiency models.|
|Envelope||Replace windows||Update windows to current or emerging “net-zero” building codes. This can be done either before or at the existing windows’ end-of-life.|
|Envelope||Upgrade wall insulation||Update wall insulation to current or emerging “net-zero” building codes. This may be combined with other envelope initiatives such as window replacement.|
|Envelope||Add roof insulation||Roofs are a main source of energy leakage. Adding to, or replacing roof insulation will help reduce energy needs. Can be most economical at the time of roof replacement.|
|Envelope||Add a Vestibule||Vestibules isolate the inside environment from the outside environment during occupant entry. Vestibules prevent the loss of heated or cooled air from escaping when exterior doors open.|
|Domestic Water Use||Install Low flow toilets and faucets||Installed low-flow toilets and faucets can reduce water use with little impact on the occupant.|
|HVAC||Install deadband thermostats and/or widen deadband zones||Usually, temperatures within a building’s zone remain comfortable between 20.6℃ (69℉) and 23.9℃ (75℉). Installing and setting deadband thermostats can maintain occupant cover while reducing HVAC heating and cooling.|
|HVAC||Replace Supply fan motor and equip with VFD or VSD||Supply fan motors have become more efficient over time and replacement can be considered even before the fan’s end-of-life. Variable Frequency Drives (VFDs) or Variable Speed Drives (VSDs) enhance efficiency further by modulating motor speeds at part load conditions, increasing overall building efficiency.|
|HVAC||RTU replacement||Whether the RTU system is at its end-of-life or the building’s function has changed and no longer aligns with the existing RTU system, a full RTU replacement with the latest technology will have a drastic impact on building efficiency.|
|Grid Power||Replace building transformer||The electric transformer that steps-down the grid power to a level suitable for building use could be considered for replacement with more energy-efficient models.|
|Generation||Investigate onsite combined heat and power (CHP) opportunities||Depending on input fuels available in your area (natural gas, biomass, etc.), a CHP system can allow your building to produce its own heat and power, reducing energy grid reliance. Discussion with internal O&M teams is a good starting point followed by preliminary technical, economic, and regulatory analysis.|
|Generation||Investigate onsite solar generation opportunities||Depending on the solar potential in your area and the layout and solar readiness of your building, installing solar photovoltaic (PV) cells for onsite generation could help offset your reliance on grid power and the power bill. Discussion with internal O&M teams is a good starting point followed by preliminary technical, economic, and regulatory analysis.|
The Efficiate Utility Information System can help retail building operators organize their building’s energy and water use data so improvements can be tracked and measured over time.