In July 2001, Northwind™ Phoenix began serving district cooling to Chase Field (formerly Bank One Ballpark) and two additional clients. With one plant located in the ballpark and another larger plant located immediately adjacent, the plants supplied 9,600 tons of cooling to the downtown area (8,000 tons to the ballpark).

In 2006, Northwind™ Phoenix began operating a third downtown plant inside the Phoenix Convention Center. This downtown Phoenix district cooling system uses three main plants and two backup plants to serve buildings that range in size from 3,000 square feet to more than 1,900,000 square feet. The system’s 20,500 ft of 24-inch chilled-water pipeline circulate 2.2 million gallons of 34-degree F water throughout downtown Phoenix to more than 12 million square feet of building space.

All told, the downtown Phoenix system now supplies 30,000 tons of cooling to 28 buildings. In addition to the City of Phoenix, clients include Chase Field, US Airways Center, Arizona Center, Arizona State University, Maricopa County, Sheraton Hotel, several Biomedical Research Facilities and many high-rise condominiums and office complexes.

A total of 14 chillers and two thermal storage tanks are employed. Each night, chillers pump a 17-degree glycol and water mixture through galvanized steel coils in the chilled-water storage tank. This produces 3 million pounds of ice (56,000 ton hours), produced when utility loads – and market prices – are lowest. During peak cooling periods during the day, the ice is melted, and the water pumped through an underground distribution network to air condition buildings. Using the ice reduces the amount of chiller that are required to run during the day, which also reduces electrical peak demand

The downtown system currently has a total capacity 40,000 tons, which will likely be sold out by 2011. Given this projection, Northwind™ Phoenix anticipates beginning design of a fourth main plant in downtown Phoenix in 2009, which will add capacity to the existing system.

In addition to assisting developers to reduce up-front capital costs and provide enhanced reliability, Northwind™ Phoenix supports the sustainability efforts of each of its service areas - each of whom are working to optimize energy-efficiency and environmental benefits to their respective communities. Northwind™ Phoenix has demonstrated a client energy savings of approximately 13% when comparing a building’s on-site energy usage before district cooling to post-district cooling connection.

Northwind™ Phoenix currently provides service to two campuses of Arizona State University, and numerous City of Tucson buildings, including the Tucson Convention Center.

Other Facts:

During its eight years of operation, the company has:

  • been recognized by the International District Energy Association as the winner of the 2008 “System of the Year” Award, recognizing exemplary system performance and service;

  • become an official partner in the CHP Partnership program operated by the U.S. Environmental Protection Agency;

  • received the ENERGY STAR Combined Heat and Power Award for Sun Devil Energy Center operations;

  • never had any environmental enforcement actions taken against it;

  • has received media attention, including the Discovery Science Channel, for its district cooling achievements.