During President Obama’s inauguration speech on Jan. 20, 2009, he said, “We will harness the sun and the winds and the soil to fuel our cars and run our factories.” Obama and the new administration believe that renewable energy is part of our nation’s successful future—possibly because the federal government has already experienced positive results.

Under the Energy Policy Act of 2005, all federal government agencies are required to use some renewable energy. One agency that's continuing to do this successfully is the U.S. National Guard with the assistance of the U.S. Army Corps of Engineers.

Recently, the Guard’s New Jersey branch sought the expertise of the Army Corps’ New York District to construct two solar-power projects for them. 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.

Solar Incentives

The State of New Jersey requires its citizens to support the use of renewable energy. Under the New Jersey Solar Renewable Energy Certificate Program, certificates are given to owners of solar systems that generate more than 1,000 kilowatts of electricity per year and are connected to the public power grid. 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 benefit with the assistance of the Army Corps.

Sun and Shade

The Army Corps is constructing two open-panel photovoltaic carport solar-power projects for the New Jersey National Guard–one for the Joint Force Headquarters at Fort Dix and the other for the National Guard Training Facility Center at Sea Girt. The carport solar-power projects are being erected over two existing parking lots at both locations. The energy generated will power these two buildings, both of which are within 200 feet of the parking lots.

The Army Corps is erecting the carport structures above the parking lots and then setting up area lighting, inverters, transformers, switchgears and electrical metering equipment. 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 panel arrays are being installed. 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 panels are composed of modules. Each module is made up of several solar cells, or photovoltaic cells, which absorb the sun’s light and produce electricity. The larger the size of the panel, the more electricity will be produced.

The panels produce electricity in the form of direct current, which is not directly usable energy for a building. Most buildings require alternating current at a higher voltage. To make usable building power, the solar panel’s DC is fed into an inverter, which transforms it into AC at a higher voltage. This AC power is then sent to the buildings’ main transformers, where it can be used for the buildings’ energy needs.

When completed, both structures, including the panels, will roughly be the size of a football field. The Fort Dix project will generate approximately 240 kW and the Sea Girt project approximately 238 kW. Both solar-power systems are also tied into the public power grid, and excess power is shared with the community.

The Fort Dix and Sea Girt projects are also being designed in a way that will save the National Guard considerable energy savings during the high-energy-demand months of summer. To allow for optimum performance, the panels are being placed at a 25-degree angle at Fort Dix and a 15-degree angle at Sea Girt. This will provide the Fort Dix building 40 percent of its summer energy needs and the Sea Girt building 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 approximately $116,000 in electric bill savings and earn approximately $350,000 from the SREC Program.

Design Benefits

Besides financial benefits, there are additional pluses 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 old roof, you will most likely have to remove these panels in the future to repair the roof as it gets older 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 to 25 years on top of a roof that has only one year left,” said Armando Jimenez, project manager, U.S. Army Corps of Engineers, New York District. “By placing panels on new rooftops, you also don’t have to deal with building or roofing permits to reinstall roof-mounted solar-power systems.”

Constructing on an existing parking lot also has its benefits. By doing this, you aren’t impacting the stormwater 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, which would require a stronger and more-expensive structural support.

Shedding Light

Jimenez says he envisions an increase in solar-power project construction in the future and has the following suggestions for builders who plan on embarking one.

Before you begin a solar-power project, seek advice from experts in solar and renewable energy because they can save you considerable time and money. In the case of the Fort Dix and Sea Girt projects, the Army Corps’ New York District collaborated with the Army Corps’ Engineer Research and Development Center, which has extensive experience working on solar-power projects with Army Corps districts, the Department of Defense and other federal agencies throughout the world.

When designing the project, make sure the buildings to which you want to provide the solar power are situated near the solar-power panels and are large enough to be able to use most of the energy or have a “big load.” The farther a building is from the panels, the more energy you will have to use to transport the solar-power energy to the buildings. “For example,” Jimenez says, “it doesn’t make sense to have solar-power panels way out in a desert because you will lose efficiency by using the energy to transport electricity from there to where buildings are that will use the energy. Due to power transmission lines having inherent resistance and capacitance, energy is always wasted when transporting power.”

You should also calculate ahead of time how much money your customer will be saving in electric bills in the long run as well as try to find out if there are any energy credit programs they can benefit from, such as the State of New Jersey’s SREC Program, so that the project is economically justified.

The Sea Girt project was completed in the summer of 2009, and the Fort Dix project is expected to be completed in summer 2010. And, according to Jimenez, 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,” Jimenez says. “We are meeting the nation’s environmental goals and President Obama’s renewable-energy vision.”