In Public Rooftop Revolution, ILSR estimates that mid-sized cities could install as much as 5,000 megawatts of solar—as much as one-quarter of all solar installed in the U.S. to date—on municipal property, with little to no upfront cash. It would allow cities to redirect millions in saved energy costs to other public purposes.
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Lancaster, CA city manager Jason Caudle, listen to the podcast, read the interview summary.
Raleigh, NC renewable energy coordinator Robert Hinson, listen to the podcast, read the interview summary.
Kansas City project manager Charles Harris, listen to the podcast, read the interview summary.
In 2012, ILSR published a pair of reports that projected, by 2021,10% of electricity in the U.S. could come from solar and at a lower price—without subsidies—than utility-provided electricity. In 2014 and 2015, Environment America’s Shining Cities reports examined how cities were catalysts for solar development.
However, there has been a missing piece in the examination of how cities can support solar energy: what city leaders have done and can do to use solar on their own buildings.
ILSR estimates that over 5,000 megawatts (MW) of solar could be inexpensively installed almost immediately on municipal property—more than a quarter of the nationwide total solar capacity through September 2014. This includes just the municipal buildings of the approximately 200 cities with 100,000 or greater population. But it requires city officials to overcome a few, surmountable barriers.
The Public Rooftop Solar Opportunity
The opportunity of municipal solar spans financial savings, pollution reductions, and job creation:
Energy Savings: New Bedford, MA, is saving $6 to $7 million per year on electricity through its 16 MW of solar installations on municipal properties, which is 2.5% of the entire city budget.
Greenhouse Gas Emissions Reductions: Maximizing New York City’s solar potential with 410 MW of solar would reduce emissions by 1.78 million metric tons, 3.7% of the city’s total emissions.
Significant Economic Impact: Maximizing Kansas City’s municipal solar potential of 70 MW could create 1400 jobs and add $175 million to the local economy.
Overcoming the Economic Barrier with 3rd Parties
The primary incentive for solar is the 30% federal tax credit, a deal that doesn’t apply to local governments. The federal government also provides accelerated depreciation for solar projects, resulting in a tax write-off worth nearly another 30% of a project’s value. The following charts illustrates how the limitations of federal incentives make the economics more challenging for municipally-owned solar.
Although cities face a number of challenges, economic and otherwise, to installing solar, the third party ownership option—if available—ought to trump most of them. For suitable sites that won’t need a near-term roof replacement, third party ownership removes virtually all of the financial barriers to solar, and covers maintenance and operations. While some barriers (like lack of aggregate or virtual net metering) remain, most cities have a substantial solar opportunity.