IKEA is a green leader in Colorado

The IKEA store in Centennial, Colorado

CaliforniaGeo 3-2–17

As what may become known as the “greenest” large retailer in the nation, IKEA  has hit a new mark for sustainability with its Centennial, Colorado store, south of Denver.  This store has two levels of underground parking, two levels of retail space, two restaurants with total  seating for 550, and contains 415,000 square feet of conditioned space.   That’s where any similarity ends between this store and any large commercial building.

1,121 KW PV system yields 1.7 Million kwh per year

Sustainability-

Long known for its use of sustainable materials and recycling for most of its products, IKEA, as a corporate veteran of solar electricity generation, has  doubled down here.  The Centennial store pushes energy efficiency toward the limit, and incorporates renewable heating, cooling, and hot water, with grid load reductions tied in part to the creation and storage of nighttime ice for the following day’s cooling.  As with most large buildings, it’s the cooling load from inside space that represents the greatest HVAC challenge.

Buffet restaurant inside the store

Headers and manifolds carry bore field loop water to and from heat pumps within the building

Historically, large buildings would use cooling towers (with their potable water  consumption) or electric air conditioners (with their heavy use taxing the grid) to get the cooling job done—particularly in warm months.  In this case, the building connects with the thermal stability of the earth, via 130 grouted geothermal boreholes, each to a depth of 500 feet, and each containing a loop of 1.25” polyethylene pipe.  The loops are underneath the building and carry circulated water to serve water-to-water and water-to-air heat pumps inside. 

Nine 1,500 gallon water/ice tanks

A portion of heat dissipation tubing area

Those heat pumps perform heating and cooling for interior spaces, and generate hot water for restaurants and restrooms.  They also use off-peak electricity during low occupancy, overnight hours to create and store over 13,000 gallons of ice that will assist with tomorrow’s cooling load.  The heat removed to make that ice is sent to the underground bore field if radiant dissipation pipes embedded in 38,000 square feet of outside walkways and parking can’t handle it alone after the store’s closing or on cool days.

Scale model shows the proportion of geo boreholes under the IKEA building

Green Awareness-

Centennial’s IKEA could be described as a mall-in-one, where shoppers and employees can both enjoy comfortable interior space and convenient food and lounging spaces without having to leave the site to seek either.  This helps reduce traffic congestion and adds to IKEA’s strong efforts for carbon reduction and environmental stewardship across its business.  The store takes pains to feature its green efforts with a scale model educational display, readily visible within public space. It can be hoped that someday, the efforts made in their Centennial store will be the default path for all new construction.

—Bill Martin