Sometimes it's good to be the first to try something new. As the first hospital in Arizona to participate in the Salt River Project's retrocommissioning program, Banner Estrella Medical Center, Phoenix, has saved significant money by reducing energy use and made the hospital more comfortable for staff and patients.

The 500,000-square-foot, 214-bed hospital saved up to $140,000, or about 8 percent of its energy costs, the first year after retrocommissioning its HVAC and other systems and then saved an additional 5 percent last year on the already-reduced amount, says Jim Mauldin, Banner Estrella's plant operations supervisor.

The Salt River Project (SRP), Banner's local utility, awarded the hospital a rebate to participate in its PowerWise Retrocommissioning Solutions program. The rebate essentially paid for the work done by an engineering firm hired by SRP that identified where infrastructure systems could be fine-tuned and how to do it, says Mauldin.

Engineers spent six to 10 months measuring and trending airflow, building pressures, and air and water temperatures at up to 1,500 set points throughout the hospital, says Mauldin. The engineers then developed an 11-point plan to achieve maximum efficiency. The hospital implemented each of the recommendations at a total cost of about $40,000, he says.