By Dr. JoAnne Castagna
Army Corps of Engineers

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hi-res photoFORT DIX, N.J. (3/24/09) -- Under the Energy Policy Act of 2005, all federal government agencies are required to use some renewable energy.
One agency that continues to do this successfully is the National Guard with the assistance of the U.S. Army Corps of Engineers.
Recently, the New Jersey National Guard sought the expertise of the Army Corps’ New York District to construct two solar power projects.
These projects will not only help the Guard meet the country's energy laws, but also save money on electricity and earn a profit from the state of New Jersey.
The state of New Jersey requires its citizens to support the use of renewable energy.
Under the New Jersey Solar Renewable Energy Certificate Program, solar system owners that generate over 1,000 kilowatts (KW) of electricity per year, that’s connected to the public power grid, receive certificates.
These certificates are then publicly sold and traded to New Jersey businesses and individuals, enabling them to receive solar power benefits without building a solar power system themselves. The revenue is returned to the solar system owners.
The New Jersey National Guard is an owner of several solar power systems. They have benefited from the SREC Program and will continue to with the assistance of the Army Corps.
The Army Corps is constructing two open panel Photovoltaic Carport solar power projects for the New Jersey National Guard – one for their agency’s Joint Forces Headquarters at Fort Dix, N.J., and the other for their National Training Facility Headquarters at Sea Girt, N.J.
The carport solar power projects are being erected over two existing parking lots at both locations. The energy generated will power these two buildings, which are less then 200 feet away from the parking lots.
The Army Corps is erecting the carport structures above the parking lots and then setting up area lighting, inverters, transformers, switchgears, electrical metering equipment.
When the projects are completed, they will restore the parking lot pavements, which are already in good shape, by re-stripping and sealing cracks.
The steel carport structures will stand 16 feet above the parking lot pavement and will be supported by web steel joists and joist girders.
On top of these structures, the solar Photovoltaic Power Panels arrays will be installed.
The panels are composed of modules made up of several solar cells or photovoltaic cells that absorb the sun’s light and produce electricity. The larger the size of the panel, the more electricity will be produced.
Electricity in the form of direct current (DC) is produced by the panels, which is not directly usable energy for a building. Most buildings require alternating current (AC) at a higher voltage.
To make usable building power, the solar panel’s DC is fed into an inverter that transforms it into AC at a higher voltage.
This AC power is then sent to the building’s main transformers where it can be used by the buildings for their energy needs. The New Jersey National Guard’s solar power system is tied into the public’s power grid and excess power is shared with the community.
When completed, both structures including the panels will roughly be the size of a football field. The Fort Dix project will generate about 240 KW and the Sea Girt project about 238 KW.
Both projects are also being designed in a way that will save the National Guard considerable energy savings during the high energy demand months of summertime.
At Fort Dix, the panels are being placed at a 25-degree angle and Sea Girt at a 15-degree angle to allow for optimum performance. This will provide the Fort Dix building 40 percent of its summer energy needs and the Sea Girt building with 80 percent.
Placing the panels on an angle also facilitates runoff of rain and snow.
The New Jersey National Guard will also earn considerable money from electric bill savings and the state’s SREC Program. In total the agency will save about $116,000 in electric bill savings and earn about $350,000 from the SREC Program.
Besides these financial benefits, there are additional plusses that come with constructing solar power projects on new open panel carports that are on existing parking lots.
If you install a solar power system on an existing building roof and not a new roof, you will most likely have to remove these panels in the future to repair the roof as it gets old and leaks, which can be very expensive and time consuming. The solar power system will also add weight or roof load to the existing roof, increasing its deterioration.
“You don’t want to install panels that can last 20-25 years on top of a roof that has only one year left,†said Armando Jimenez, project manager for the U.S. Army Corps of Engineers’ New York District. “By placing panels on new roof tops you also don’t have to deal with building or roofing permits to reinstall roof mounted solar power systems.â€
Constructing on existing parking lots also has its benefits. By doing this you aren’t impacting the storm water runoff so there are minimal impacts to the environment.
In addition, vehicles using the parking lot receive some shading from the sun.
An open panel carport design is also a smart way to go. An open panel as opposed to a solid ceiling structure prevents debris, such as bird nests and snow, from accumulating on the carport, which would require regular maintenance.
Also, a solid ceiling adds additional weight to the structure that would require a stronger and more expensive structural support.
Both solar power projects are expected to be completed sometime this fall, and Jimenez said the New Jersey National Guard has asked the Army Corps to perform additional solar power projects in the near future.
“These solar power projects are a win-win for the community, U.S. National Guard and the nation,†he said. “We are meeting the nation’s environmental goals and President Obama’s renewable energy vision.â€