In fact, the U.S. Department of Defense (DoD) could generate a total of seven gigawatts (GW) of solar energy at four installations in the California desert, according to the findings of a feasibility study released this month by the agencys Office of Installations and Environment. Thats as much as the combined production of seven nuclear power plants, or two-thirds of the electricity that the military uses nationwide each year.
The comprehensive 12-month study, requested by the U.S. Congress and conducted by the Fairfax, Virginia-based environmental consultancy, ICF International, determined the "solar compatibility" of seven DoD bases in Californias Mojave and Colorado deserts, as well as two command centers in Nevada.
ICF found tremendous energy potential, despite the fact that fully 96 percent of the DoD property was deemed unsuitable for solar development for a number of reasons, including:
- Security required for military drills and missions, as well protection of radio frequencies and other communications or surveillance technologies;
- Topographic issues (such as steep slopes and flash -flood hazards);
- Biological resource conflicts (for example, protected species); and
- Cultural constraints (among them, the Native American property rights to the Fort Mojave Indian Reservation).
Taking all of this into consideration, about 25,000 acres in the Mojave Desert are "suitable" for solar development and another 100,000 acres are "likely" or "questionably suitable". None of the property in the Colorado Desert, part of which extends into California, or in Nevada was found to be solar-compatible.
The largest amount of appropriate acreage is located at Edwards Air Force Base (24,327 acres), a site that is familiar to worldwide television audiences as the field where NASA’s Space Shuttles land. Property also is available for development at the Fort Irwin U.S. Army installation (18,728 acres), Naval Air Weapons Station China Lake (6,777 acres) and Marine Corps Air Ground Combat Center Twentynine Palms (553 acres).
The Department of Defense is seeking to develop distributed energy sources on its bases both to reduce its $4 billion-a-year energy bill and to make DoD less dependent on the commercial electricity grid. On-site energy generation, together with energy storage and smart-microgrid technology, would enable a military base to maintain its critical operations "off-grid" for weeks or months, if the grid is disrupted.
The study suggests that only private investors would find it attractive to invest in these projects, because they have access to U.S. federal and state tax-based incentives. The most important federal solar tax incentive – the Investment Tax Credit (ITC) created by Congress in 2005 – is expected to be available through the end of 2016; but it is possible that legislative action in the interim could phase out or eliminate this incentive, which would make private investment less appealing.
The research identified crystalline-silicon photovoltaics with single-axis tracking as the solar technology with the highest projected investment returns, due to its combination of low-cost installation and high electricity output. The other photovoltaic technology packages analyzed also would generate attractive financial returns on many large sites.
Assuming private development and ownership of economically-feasible solar capacity on the four California installations, the federal government could expect to receive more than $100 million annually, in the form of rental payments, discounted power, in-kind considerations, or some combination thereof. Full development also would help the United States to avoid emissions of millions of tons of greenhouse gases and other air pollutants.
While complete development of all of the identified solar energy potential is unlikely, enabling full solar development on approximately six percent of the identified, economically-feasible lands would generate enough electricity to meet all of the DoDs EPAct 2005 renewable energy goals. Solar development on less than half of the identified lands would be sufficient to meet all of the DoDs NDAA 2010 renewable energy goals – that is, 25 percent of facility energy produced by renewable energy sources as of 2025.
Whats next? In order to expedite the development of solar energy on military bases, DoD must confront and solve two major issues. First, DoD must work with the Department of the Interior to clarify the status of "withdrawn lands" – that is, lands that are not available for public use. Withdrawn lands comprise the majority of the property considered in this study, and resolving their status and potential use in third-party financed projects is critical, if the DoD intends to develop utility-scale solar energy projects.
Second, the lack of transmission capacity is the single largest barrier to large-scale solar development on the four California installations. The DoD and the many other stakeholders affected by this constraint could increase their efforts to encourage transmission owners and planners to expand capacity on existing transmission lines and hasten the necessary transmission build-out.
In related news, most of the installations considered in this study already have one to two megawatts (MW) of solar energy systems in operation, and Nellis Air Force Base in Nevada is host to the largest photovoltaic system sited on a military facility in the United States – a 14.2 MW photovoltaic facility completed in 2007.