UPDATE: First ever net zero energy store by Walgreens relies on CO2 heating and cooling 

By Janaina Topley Lira, Nov 25, 2013, 11:00 3 minute reading

Walgreens, the largest US drugstore chain is investing in CO2 refrigeration for heating and cooling as part of its commitment to build its first net-zero energy store in South Evanston, Chicago. Update: The new store, opened on 21 November 2013, replaces an old Walgreens store, and in addition to the CO2 refrigeration system integrates a series of energy saving green technologies.

"We are committed to reducing our carbon footprint and leading the retail industry in use of green technology," said Thomas Connolly, vice president of facilities development for Walgreen, in a statement. "We are investing in developing a net-zero store so we can learn the best way to bring these features to our other stores. Because we operate 8,000 stores, we believe our pursuit of green technology can have a significant positive impact on the nation's environment."

“We are opening around 150 new stores a year, so we intend to take the learnings from this project and be able to apply them to our existing store base as well as new stores,” said Janie Meyers, Walgreens Sustainability Manager at the opening of the store on 21 November.

CO2 refrigeration integral to net zero energy project
The Walgreens CO2 heat pump and refrigeration designs are based around a triple temperature range CO2 system made by Swedish company Green and Cool. Such systems enable the use of R744 with three different evaporation levels.
Rejection heat from the refrigeration equipment will be used to heat the Evanston store. Rejection heat from the refrigeration equipment is used to heat the Evanston store. The CO2 transcritical system, designed in Sweden and manufactured in France, saves 60% energy compared to traditional technology, pointed out Walgreens Engineering Manager, Jason Robbins.

Green technologies achieve 40% energy savings
Walgreens plans to generate electricity and reduce energy usage by more than 40% through several technologies, including: 
  • Solar energy: 800 rooftop solar panels on the store's tiered roof
  • Wind energy: 2 wind turbines 
  • Geothermal energy: a 550-foot-deep (167.6m) well will help regulate extreme temperatures 
  • Lighting: natural daylight instead of artificial lighting wherever possible. LED cooler and freezer lighting
  • HVAC&R systems: carbon dioxide refrigerant for heating, cooling and ultra-high-efficiency refrigeration equipment

It is estimated that the Walgreen’s store, which will replace a store that is currently being demolished, will use approximately 200,000 kW hours per year of electricity, and generate about 256,000 kW hours per year.
Bid for LEED Platinum status 
In addition to entering the store into the International Living Future Institute’s Living Building Challenge, Walgreens is hoping to achieve Leadership in Energy and Environmental Design (LEED) platinum status, the most stringent designation by the US Green Building Council. This would make it the third LEED-certified store for Walgreens.
The store will also be Walgreens second showcase project in the U.S. Department of Energy’s Better Buildings Challenge.
PURE, Walgreen’s corporate sustainability program
Walgreens has around 8,071 drugstores in all 50 states of the U.S. and including the District of Columbia and Puerto Rico. Through the company’s corporate sustainability program, “PURE Walgreens – For the health and wellness of our planet,” the company hopes to become a leader in resource conservation, carbon emissions reduction and waste diversion.

To follow the new store’s two-year journey to achieve net zero status and to find out more, readers can visit the Net Zero Facebook page at: 



By Janaina Topley Lira

Nov 25, 2013, 11:00

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