The SUNDA project officially closes this month amid a cooperative solar landscape that is dramatically different from the one that existed four years ago when the initiative kicked off.

"The SUNDA project succeeded because of Cooperative Principle No. 6: cooperation among cooperatives," said Debra Roepke of NRECA's Business and Technology Strategies group.

"SUNDA partner co-ops cooperated with one another to explore and implement options. Lessons from their real-world experience formed the core of a set of tools that have already been used by hundreds of other co-ops across the nation."

NRECA's Solar Utility Network Deployment Acceleration project was financed in part with a Department of Energy Sunshot Initiative grant. Its goal was to advance research and testing of systems that would help expand solar energy technologies.

"The DOE grant enabled NRECA both to support early solar adopters and collect data and case studies that provide insight into challenges and solutions related to the technology," said Roepke, who served as NRECA's co-project manager and liaison to SUNDA participants. "The results have helped spur interest in a wide range of co-op projects from utility-scale solar to community solar ownership and leasing programs to oversight of vendor programs."

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Seventeen distribution and generation and transmission co-ops of various sizes in diverse locations with a wide range of climates initially participated in SUNDA. Dozens of others benefited from the research and updates provided regularly over four years.

"The partner co-ops collaborated with one another, generously shared their challenges and successes, and contributed to a rich array of resources that will continue to support co-ops as they navigate the changing energy landscape," Roepke said.

Total solar capacity owned or contracted by electric cooperatives rocketed from 94 megawatts to 868 MW, a nine-fold increase, between 2013 and 2018. Electric co-ops now host 75 percent of all utility-sponsored community solar projects and have developed several programs designed to give low- to moderate-income members access to solar.

The research has built a broad co-op knowledge base, producing field manuals, business models, finance and insurance prospectuses and procurement guides, and establishing a framework to accelerate technology adoption by co-ops.

"CoServ Electric's 2-megawatt AC solar facility, the CoServ Solar Station, was the first system using NRECA's modular engineering designs to come online," said Curtis Trivitt, senior vice president of energy services for the Corinth, Texas-based distribution co-op. "Using these resources helped CoServ keep the project cost at less than $2 per watt, which was one of the interim goals of the SUNDA project."

Roepke touted the program's resource for making solar feasible for members of all income levels.

"While interest in solar is gaining momentum, we recognized that a number of approaches will be needed to ensure that co-ops have affordable options to make the technology available to members who want it," Roepke said. "Solar may not make sense for every co-op, but we now have a toolset—made by co-ops, for co-ops—that enables any co-op to objectively assess their solar options and support implementation."

Fall Creek, Wisconsin-based Eau Claire Energy Cooperative was an early participant in the SUNDA program, launching a 750 kilowatt community solar project first with purchased shares. When subscriptions plateaued, the co-op looked to a more flexible model used by another SUNDA participant.

"Many working families can afford to invest $20 a month into solar, but a couple of thousand dollars would strain their budgets," said Lynn Thompson, CEO and general manager at Eau Claire Energy.

The pricing change worked.

"Our project is now fully subscribed with all panels leased," said Thompson. "Monthly payments allowed us to serve a different segment of our membership. Had we not changed our pricing model we might not have gotten there."

Some SUNDA participants see the research providing a model not only for solar projects but for other emerging technologies, including energy storage.

"We're using the SUNDA materials in development of a microgrid project," said Kevin Short, CEO and general manager of Anza Electric Cooperative, one of the original SUNDA partners. "The engineering is particularly beneficial for focusing on utility-scale projects."

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