January 13, 2017 - Energy Manager Today
The Northport VA Medical Center Handles a Cooling Tower Crisis On March 10, 2015, The Northport Veterans Affairs Medical Center was presented with a big problem: The piping connecting four cooling towers that served two buildings on the large campus ruptured and lost all cooling capacity.
The buildings are part of a nearly century old, 200-building, 1.4 million square foot facility on a 253-acre site on the north shore of Suffolk County on Long Island, New York.
In the short term, temporary air-cooled chillers were brought in and service was restored within 48 hours, according to Facility Chief Engineer Ronald Brattain. Clearly, however, more significant fixes were necessary. The next step was to determine a path forward. The VA entered into a $15.5 million, 15-year utility energy service contract (UESC) with National Grid, the utility that serves Long Island. National Grid contracted with ConEd Solutions to assess the job and perform the work. ConEd Solutions settled on four cooling towers from Evapco and ancillary pipes, pumps and controls from Johnson FX Controls, said Jason Masters, the VA Project Manager.
Masters said that the equipment has a life expectancy of 25 years and will pay for itself in about half that time. Annual energy savings are thought likely to be $90,000, which is 15 percent to 23 percent less than previous average expenditures. However, the unplanned nature of the project means that the baseline is a less certain than in other instances.
UESCs are different than energy service performance contracts (ESPCs) in two of key respects. The first, as the name implies, is that they are between the utility and the end user. The utility then separately contracts with vendors for the work. The main contractor in an ESPC is an energy services company (ESCO), not a utility.
Masters said that the UESC was chosen due to the need for expediency. “We needed to [put something in place] as quickly as possible,” he said. “UESCs are the faster contractor vehicle… The utility providing services has the ability to enter a private contract a lot quicker” than in an ESCO, he said.
A second difference is the level of certainty. Savings are guaranteed in an ESPC. If that savings falls short, the ESCO is liable for the difference. In an UESC, savings are “assured,” which is a materially different arrangement. In this scenario, if agreed upon savings are not realized in a particular year, the utility sends back its contractors to make necessary changes. If problems persist in the second year, the problems are then addressed and a monetary agreement reached.
The most dramatic day of the project was November 5, 2016. The challenge was the positioning of the buildings. “The way our hospital is built it is not economically feasible to bring in a standing crane,” Masters told Energy Manager Today. “It is more economical for our facility to bring out an air crane.”
It was a precision operation, and the team spent 63 days planning every detail. Work began at 5:30 AM. Expectations were that it would last 13 to 14 hours. A Sikorsky S-64 Skycrane – which is 107 feet long and has a rotor diameter of 88 feet — was used to bring in the new towers, which measure about 30 square feet and are about 12 feet tall. The helicopter also removed the old towers and associated debris.
The buildings were not emptied during the operation, though sections were closed when the helicopter was overhead, Brattain said. In all, 44 round trips were made to and from the staging area, which was about a quarter mile away.
One adjustment was made on the fly, so to speak. A full fuel tank and a 22,900 pound tower was too much. Before the first trip, the Sikorsky burned enough fuel to do the job safely. Refueling therefore was necessary after each round trip, which consisted of about two to three minutes of transit time and about 90 seconds at the site. At that point, the new tower is put in place and, if necessary, debris loaded for transport out of the operational area. In all, 22 round trips were made. The job was completed in about four hours less than what was called for in the initial schedule.
The installation is expected to be completed in June. The Northport Veterans Affairs Medical Center achieved two notable things since the day that the old cooling towers went off line: They improvised to keep the buildings open and serving veterans in the short-term and created a solid longer term plan that will, if all goes according to predictions, save money and improve efficiency.