New boilers can provide savings in fuel and water treatment costs - or drive expenses out of line. Therefore, when Shelby Baptist Medical Center was selecting equipment to supply heat and steam for essential services at its $94 million South Tower and central energy plant, it chose carefully.
Ultimately, facilities director Frank Hutchinson selected three EXN-300SGO dual-fuel steam boilers from Atlanta’s Miura North America Inc., for maximum steam generation efficiency at the new Alabaster, Ala., medical facility.
After looking at the engineering plan and doing the numbers with Miura’s representative, Marspec Technical Products in Spanish Fort, Ala., “we found that only three 300 BHP units were needed instead of the proposed three 400 BHP boiler configuration,” Hutchinson says. “I made them [the engineering firm] run the numbers again and they agreed that I was right and acknowledged the projected $60,000 per year savings on natural gas costs revealed by the calculations.” Taking matters into his own hands, Hutchinson rejected the engineering firm’s plan and substituted three 300 BHP Miura EXN-300SGO dual-fuel boilers to replace the four proposed firetube units.
“I really stuck my neck out on this one, but it was the right thing to do and I’m very glad I did,” he says. The hospital’s South Tower Project consists of a new 167,712 ft2four-story tower housing 101 patient beds with additional space for other hospital services, including a surgery center, clinical laboratory, central sterile supply department, admitting/registration area, and public and mechanical spaces. The tower is powered by a 15,000 ft2central energy plant with three Miura dual-fuel boilers providing steam for heating the tower as well as powering a surgery center and the hospital’s central sterilization unit.
Marspec Technical Products, under the supervision of Craig Simons, installed the boilers. And, since the tower’s opening in December 2009, the Miura boilers have been proving their value.
“The new bed tower encompasses more square footage than the old hospital wing and we have moved the surgery center, cath lab and central sterilization into the new tower as well,” Hutchinson says. “Even with this substantially larger load, we are seeing a 35 to 50 percent reduction in fuel costs compared with running the old facility. And with annual fuel costs exceeding $400,000, these new Miura boilers can pay for themselves in just a few years time.”
While the new tower incorporates a number of energy saving features in its design and construction, Hutchison attributes about 30 percent of the energy savings to the Miura boilers, which save money in a number of ways.
First, their on-demand steam technology employs a once-through design that produces usable steam output in five minutes. This allows fuel savings and eliminates the need for many hours of full-power operation each week.
Second, the rapid startup of the on-demand steam boilers allows multiple-installation users to turn off any boilers not in use, eliminating the fuel expense of having boilers idling in standby mode. Third, Miura’s modular design allows multiple-installation boilers to be switched on and off to match varying load demands throughout the day. The system will respond automatically to increased demand or switch to standby once the demand has been met. Because the Miura boilers heat much smaller quantities of water than larger firetube boilers, turning a boiler off results in less radiant losses.
Finally, the boilers conserve water and save on water-treatment costs.
The medical center plans to eliminate two existing 200 BHP firetube boilers in the hospital’s older section and connect the older area to the new Miura-powered central energy plant. The three new boilers can handle the additional load without needing to install additional units. Anticipating this move, Hutchinson says that his water-treatment company has already reduced his upcoming water treatment contract by $20,000 a year to account for the loss of the older 200 BHP boilers.
Being placed in charge of deciding which type of boiler the Shelby Baptist Medical Center would rely on for many years "was a big responsibility, which I didn’t take lightly,” Hutchinson says. “In that position, the easiest thing to do would have been to go along with the engineers’ recommendations. But I did my own research and discovered a better solution to SBMC’s needs.”