By Julia BobickAugust 8, 2014
HUNTSVILLE, Ala. - The U.S. Army Corps of Engineers' first and only Energy Savings Performance Contract (ESPC) to include wind power generation is nearly complete at Fort Buchanan, Puerto Rico. One of several energy conservation measures implemented through the ESPC, two wind turbines will produce an estimated 5 percent of the energy consumed by the installation. In addition, a total of 21,824 solar photovoltaic panels will produce about 5.5 megawatts of power, which is at least 60 percent of the installation's current power demand at its peak production.
Through the ESPC, managed by the U.S. Army Engineering and Support Center, Huntsville, the Army has also replaced old chiller systems, and package and split-type air conditioners with more efficient units, replaced rooftop mounted package air conditioners with a central chiller plant at the post exchange, installed cool roofs and energy management controls, replaced window-type air conditioners with mini split inverter-driven units, installed LED lighting and other efficient interior and exterior lighting systems and installed solar thermal water heaters.
Two ESPC measures instrumental toward helping Fort Buchanan achieve the Army's Net Zero water program goals were the implementation of a potable water well to reduce reliance on Puerto Rico's Aqueduct and Sewer Authority and installation of a 2 million gallon irrigation lake fed from a previously government-installed, non-potable ground water well that will supply the necessary water to a new irrigation system at the post golf course, according to Yamil Hernandez, Fort Buchanan Directorate of Public Works Environmental Division.
"In combination, all measures are expected to save about 30 percent of the fort's energy demand and 60 percent of potable water demand, well in excess of current federal requirements," Hernandez said. Estimated savings resulting from all the conservation measures is more than 59,000 MBtu per year and more than $4 million in avoided costs.
Through an ESPC, an energy services company provides the capital and expertise to make comprehensive energy and water efficiency improvements or implements new renewable energy capabilities on government facilities and installations, and maintains them for a specified time period. There is no upfront investment by the Army, according to Wes Malone, project manager at the U.S. Army Engineering and Support Center, Huntsville, which manages 85 to 90 percent of the Army's ESPC portfolio.
"With an ESPC, your energy budget doesn't go down; you still pay for your utilities and the savings pay for the service through a given payback period," Malone said. "The utility bill is reduced by the energy conservation measures that were implemented, but the extra money goes to the contractor to pay for the work that was done and continued maintenance of the new systems.
"The high utility rates in Puerto Rico, which at 28 to 30 cents per Kwh are nearly double the rates in the continental U.S., make ESPC renewable energy projects very attractive options for the Army," Malone said. "In any ESPC, you have to factor in the amount you pay in utilities and the financing interest rate to determine how much work you can do for a project to still be in the Army's best interest."
Photovoltaic installations in Puerto Rico have a payback of about 20 years, in contrast to an average of 37 years in the continental U.S., according to Hernandez.
"For this reason, we have also required that for all new construction on post at least 33 percent of the building's daytime power needs be supplied through solar photovoltaic energy in order to ensure energy independence," Hernandez said. "By being more self sustainable and applying sustainability principles in our building designs, revitalizations, construction, retrofits, and operation and maintenance, we not only help ourselves to be more independent and augment our operational readiness, but also help our neighbors to have a more stable power and water infrastructure capacity."
While the ESPC project is essentially complete, the second of two task orders is waiting on a separate Huntsville Center Facilities Reduction Program project to be wrapped up before the final closeout steps can be taken by the Energy Savings Contractor, Johnson Controls Inc., which was awarded the $34 million ESPC at the end of 2012.
"In many locations we have overlapping installation support projects, requiring synergy between the projects so the timelines fit together like a jigsaw puzzle," Malone said. "Together, all of the projects are helping Fort Buchanan reduce its energy consumption and improve efficiency."
The work is helping the installation pave the way toward achieving the Army's Net Zero installations goal of producing as much energy as it consumes by the year 2030, Hernandez said.
"Without the ESPC, we would still be facing rising energy and water costs, which in turn hinder our ability to provide quality services to our Soldiers, civilians and their families," he said. "Simply put, the higher the operational costs, the fewer services we are able to provide, which is not an alternative. The ESPC has basically curtailed the rise of utility costs, provided better facilities to our customers and augmented their comfort, while enhancing readiness."