An Earth Day Review: Energy Efficiency at City Market
By Brent Demers, Facilities Manager
Cooperative values are guided by seven principles. The seventh principle, Concern for Community, is where cooperatives work for the sustainable development of their communities through policies approved by their members. City Market demonstrates this principle in many ways, one of which is energy efficiency and striving to continually reduce our carbon footprint.
With the support of our members, City Market placed 136 solar panels on the roof in 2010. Since installation, the electrical generation for this 31.28 KW system has been 76,728kwh. This equals about 6,214 gallons of gas saved or the use of 437 60-watt bulbs, based on 8 hours-per-day use. City Market has a monitoring display system to the left of the Customer Service desk which provides real time information and we have photos and videos about “going solar” posted on our website.
After the successful solar installation, we continued to focus on energy savings and began working with Leading Edge Design Group, a New England company that specializes in the latest LED lighting technology. LED stands for “light-emitting diode” and this type of lighting is used for a diverse array of applications, offering lower energy usage and a longer lifespan than other lighting. Metal Halides were the standard of efficiency when City Market was built, but technology has created better options since that time. Since working with Leading Edge Design, we have retrofitted 180 track heads (ceiling lights) from 70w metal Halides to 33w LEDs and replaced the lights in 22 freezers with LEDs that dim to 50% when motion is not detected. In addition, we replaced fourteen 400w lights with 160w fully adjustable Digital Lumen LED’s, the most advanced lighting control technology on the market, allowing us to increase our energy savings along with having the capability to monitor how much energy each light is using.
After measuring significant energy savings, we replaced lights in a variety of departments with the Digital Lumen technology and then followed with replacement of the parking lot lights. In respect to the parking lot, not only did we achieve additional energy savings, but we also were able to improve the quality of lighting coverage by providing better visibility and increased safety in the parking lot. So far, with all of our LED projects combined, we have recognized a total annual savings of 128,315kwh, almost twice the amount of total savings we receive from solar over the past two years.
The Co-op also saves energy with our Digital Diagnostic Controls (DDC) system, which allows us to control most of our main HVAC (heating, ventilation, air conditioning) systems as well as many of our lights inside and outside of the store. These controls allow us to turn lights on and off based on a schedule and the HVAC can be dialed in to run with the highest possible efficiency.
With LED retrofits to date, the solar panel installation, and the DDC system, City Market save a total of 214,904kwh, or an estimated $26,000 in annual electrical savings. This next fiscal year (starting July 1), we plan to continue with more LED projects and control system additions that will reap additional energy savings of at least 30,000kwh. Our partnerships with the Burlington Electric Department, Leading Edge Design Group and Efficiency Vermont have led to many improvements – in energy savings, lighting quality and access to rebates - allowing us to be responsible stewards and sustainability leaders in our community. We look forward to building on these partnerships in the future!