Project Merit: Solar Power

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Borrego Solar (San Diego) for its business growth over the last year, and for its innovative engineering work in developing solar PV projects on capped landfills and designated brownfield sites. By bringing its financing and technical expertise to this segment, Borrego Solar is supporting a trend in which municipal and private landfill owners are increasingly identifying sites with limited reuse potential and exploring the development of large-scale distributed generation and net-metered solar PV installations.

In one of the largest capped-landfill projects to date, Borrego Solar worked with the City of Easthampton, Mass., to develop a 2.3 MW (DC) photovoltaic system that went online in the summer of 2012 and is expected to produce 2.8 GWh annually, contributing substantially to the city's general fund and its clean energy goals, making the City of Easthampton one of the state Department of Energy Resources' designated Green Communities.

Borrego Solar and other PV developers are targeting capped landfills as ideal locations, because in most cases the properties can't be developed for anything else. Additionally,  the generated savings from the solar power installations can offset O&M costs currently plaguing the cities where the sites reside. Landfills with existing gas-to-energy projects are more ideal for solar energy systems, because they have an electrical infrastructure already onsite, further reducing solar development costs while providing savings to the lessors.

The Easthamptom Oliver Street landfill project also pioneered replicable mounting techniques that meet the stringent load requirements of landfills. Borrego Solar's engineers designed the ballasted ground mounted racking system with concrete blocks, each weighing 5,000 lbs. The ballasted system allows for the installation of the PV modules without penetrating the protective membrane (or cap) of the landfill. Support beams and pylons used in traditional ground-mounted solar energy systems wouldn't work. Additionally, structural engineers determined a weight per square foot limitation that required the use of special crane and trucking equipment on the property during the construction process.

Tioga Energy (San Francisco) for completing in fall 2012 a 3.34 MW distributed solar PV project incorporating 30 separate publicly owned facilities in Union County, N.J. The systems, mounted on rooftops and carports at schools, libraries and other public facilities, range in size from less than 10 kW to almost 500 kW.

The project was the result of a public-private partnership begun in 2010 between Tioga and Union County Improvement Authority, a public agency that assists local governments in Union County to finance infrastructure projects. After responding to a UCIA request for proposals, Tioga and the public agency worked out a financing arrangement to make the most out of the public agency's bond authority, revenue streams from solar renewable energy credits (SRECs), electricity payments from the public agencies receiving the power and the federal 1603 grant in-lieu-of tax credit program.

The UCIA issued Guaranteed Renewable Energy Program Lease Bonds in 2011, then used the proceeds to pay Tioga Energy to build the systems. In a sale-leaseback arrangement, the UCIA retained title to the assets, then leased the systems to Tioga, whose payments met UCIA's financing costs and covered its professional fees for project development, according to the UCIA's report on the projects.

Tioga Energy sells power to the host facilities at rates approximately 50% lower than those of the local utility for 15 year terms using Tioga's open-source SurePath Solar power purchase agreement. All systems were installed through a joint venture between Pro-Tech Energy Solutions and Huen Electric, Inc, with environmental and engineering management firm Whitman providing design services.

Although Tioga Energy designed these systems to withstand extreme weather conditions, no one expected an immediate structural strength test. Hurricane Sandy ripped through Union County in October, forcing 13 towns in the region to declare a state of emergency. In the aftermath of the storm, each of the 30 solar installations emerged unscathed.

Marin Energy Authority (San Rafael, Calif.) for leveraging its liberal community's deep support for clean renewable power to create a robust local feed-in tariff program that is spurring investment in distributed solar PV and other renewable projects.

In a state where many renewable power advocates have looked longingly for more than a decade at the favorable FiT policies in Europe, the state has only adopted a market-reference price FiT that hasn't stimulated significant investment. The FiT offered by MEA's Marin Clean Energy division is a 20-year power purchase agreement at wholesale prices starting at $100.57 per MWh for intermittent sources (wind), $116.49 for baseload energy (landfill gas, biomass, and fuel cell) and $137.66 for renewables that deliver peak energy (photovoltaic solar and solar thermal).

Last year, MCE signed a 20-year PPA with developers of a 972 kW PV project-the largest in the county to date-that is spread across aircraft hangar rooftops at the San Rafael Airport. And it is looking for more projects up to its 10 MW cap. (Energy from renewable projects can also be developed to directly offset usage through MCE's Net Energy Metering program in which production is credited at the retail rate plus a $.01/kwh.) The airport project was developed by REP Energy, is being constructed by Synapse Electric, and was financed 50% by Bank of Marin and 50% by Joe Shekou, a developer who owns the airport.

MCE is the first instance of a local energy procurement and marketing entity formed in California through what is known as community choice aggregation. CCAs like MCE take over energy buying and selling from the local investor-owned utility-in this case Pacific Gas & Electric-while the utility continues delivering the energy and operating and maintaining the grid in exchange for a per-kWh surcharge.

Enabled by legislation intended to address the market power abuses that contributed to the 2000-2001 California energy crisis, the CCA model has become a rallying point for those who want to see even higher proportions of renewable energy on the California grid than the 33% by 2020 currently mandated for investor-owned utilities. Since MEA's founding in 2010, other local governments have joined, including the City of Richmond, and MEA's customer base is expected to be more than 110,000 by Q2 2013 according to California Energy Markets. More than a dozen other California local governments-including a consortium in the East Bay-are either developing CCAs or exploring the option.