MM&D MAGAZINE, MARCH/APRIL 2011
When Walmart Canada Corp opened its new fresh food distribution centre (DC) in Balzac, Alberta late last year, the company also introduced Canada’s most innovative and sustainable facility. In fact, the company says it’s one of North America’s most energy-efficient DCs.
The new 400,000sqf facility began as a concept 18 months ago, says Karin Campbell, a spokesperson for Walmart. The company’s senior vice-president of supply chain and logistics was just in the planning stage for building the new DC when he challenged himself and his team “to build the most sustainable one possible, with the added challenge of delivering a return on investment,” says Campbell.
The facility—which will serve as a hub for fresh and frozen food destined for 104 of the company’s stores in Western Canada, from Manitoba to BC—cost Walmart $150 million to build, and boasts some high-tech, sustainable bells and whistles. The company estimates the facility will be 60 percent more energy efficient than its traditional centres, and expects its sustainability features to help the company eliminate approximately $4.8 million in energy costs over five years.
One significant sustainable feature is hydrogen fuel cells, a pilot project for the company. According to Campbell, the DC has a fleet of 71 material handling vehicles, which all use hydrogen fuel cells for power. Using fuel cells reduces C02 emissions from the vehicle fleet by 55 percent, or an estimated 530 tonnes annually, the equivalent of taking 101 passenger vehicles off the road per year.
Traditionally, says Campbell, these vehicles would have had lead-acid batteries as a power source. “You’d have to physically change out the battery and have it re-powered. So there was the downtime of the vehicle. Now there’s a hydrogen fuel station within the building and it takes a matter of minutes to refuel. So there are a lot of operational benefits,” says Campbell. “Also we didn’t have to build a large square footage area to house a battery changing facility.”
The facility’s motion-activated LED lighting is another significant feature. LED lighting doesn’t create heat, a benefit in a cooled-down environment. It also has instant on capability. “Typically, for safety reasons, a traditional incandescent light would have to be left on because in a cooled environment it couldn’t strike back on instantly. LED lights can,” explains Campbell. According to the company, using LED lighting will save an estimated seven million kilowatt hours of electricity over five years, and help it avoid an estimated $645,000 in costs over the same period. Per year, that’s enough electricity to power approximately 121 average-size Canadian households.
Cool it down
In addition, the site uses smart refrigeration, which means it uses ammonia instead of ozone-depleting freon. That translates into a system that is 33 percent more energy efficient. Designed with a demand-response capability, the refrigeration system is also able to draw electricity during off-peak grid times. Waste heat from the system is used to keep the sub-floor frost-free in the winter. Over five years it’s estimated that using smart refrigeration will help avoid approximately $2 million in costs.
Campbell says the company custom-designed its dock doors and doorways. Traditionally, dock doors have windows. But the Walmart team determined that the window was a huge point of cooling loss in a refrigerated building, so it worked with the manufacturer and redesigned the dock door to eliminate the window.
The company custom-designed doorways between temperature zones to be more energy-efficient, and it reduced the gaps between transportation vehicles and dock doors to minimize the loss of refrigerated air. Insulation was then installed in levellers, further reducing energy loss.
Finally, electronic monitoring ensures that dock doors are not left open unnecessarily, while automatic doorways between temperature zones produce an airflow pattern that keeps different temperature air in respective zones, minimizing energy loss in refrigerated areas.
Walmart has also installed thermal panels and a 30-kilowatt wind turbine on the facility’s grounds, with another on the way. Campbell says it’s the company’s first wind installation in Canada. The two turbines will generate about 100,000kwh per year each, or enough electricity to power 40 homes annually. Sixteen solar thermal panels on the facility will provide energy to heat domestic hot water for use in offices and maintenance areas. The solar array will produce a peak of more than 205kwh per day, equal to heating the water of 20 homes with 40-gallon tanks.
There are no plans to build another facility like this, but Campbell says there are plans to take some of the best practices and retrofit other DCs in Canada. Even competitors are interested, and Walmart has welcomed them, school groups and the community in to view the site.
The new facility and its sustainable features all comply with Walmart’s three sustainability goals, launched globally in 2005: to be powered 100 percent by renewable energy; to be a zero-waste business; and to sell products that sustain resources and the environment. “Certainly we’re a company committed to being more environmentally sustainable, and for us this is a large step forward,” says Campbell. “It’s important to us because we’re not going to get to some of these goals tomorrow. It’s crucial to pilot and look at the viability of renewable energies and energy efficient technologies. So this [DC] is really an important living laboratory of sustainability to help us determine what more we can do down the road as a business.”