Sandia LabNews

Sandia leads reliability workshop for the growing field of photovoltaic systems integration


Jennifer Granata and Michael Quintana, seen here at SandiaÕs National Solar Thermal Test Facility, recently led a workshop on photovoltaic systems integration to encourage the use of PV power. Read about the workshop on page 3. (Photo by Randy Montoya)

If you build a car using the finest automotive parts but don’t connect the engine’s energy to the wheels, you won’t get very far. Similarly, installing state-of-the-art photovoltaic (PV) panels is an exercise in futility unless the power sources are expertly connected to the grid.

Jennifer Granata and Michael Quintana, seen here at Sandia’s National Solar Thermal Test Facility, recently led a workshop on photovoltaic systems integration to encourage the use of PV power. (Photo by Randy Montoya).

As the nation increasingly turns to solar power, utility companies turn to photovoltaic integrators to reliably and safely transmit that power from the panels to the grid, and, ultimately, the customer. While PV has been used for decades nationwide, integrating such an unprecedented amount of PV-generated power is relatively uncharted territory.

Sandia’s PV team and DOE recently hosted a workshop specifically for PV systems integrators in San Jose, Calif., to encourage the adoption of reliability tools in the growing area of photovoltaics in the US energy portfolio. The program focused on mitigating risk, reducing the levelized cost of energy, and improving the appeal of PV systems by calculating the relationships between initial cost and performance, long-term reliability, and lifetime costs.

“Sandia’s program focuses on systems-level work, and we are reaching into Sandia’s historical knowledge of applying reliability methods to complex systems,” says Sandia researcher Jennifer Granata (6335). “Providing reliability tools and leadership in this area is really needed within the industry, and it was a natural fit for us to lead this workshop.”

The two-day workshop included representatives from 15 integrator companies. “I was pleased with how much the national laboratories are doing, how interested they are in integrator input, their willingness to employ resources, and their desire to ensure their work has relevance to real-world construction issues,” says Peter Molloy, senior estimator with Stellar Energy, a California-based solar energy integrator. Ensuring that Sandia’s tools and research are relevant to construction issues has been one of the researchers’ goals for years.

“Open discussion with stakeholders was very useful,” says Sandia researcher Michael Quintana (6338). “We have been building and adapting tools that we would like the industry to adopt, and this workshop provided us with valuable feedback about what is helpful and how we can continue to advance the state of the art in PV systems reliability.”

Jennifer and Michael are compiling the feedback and will distill it into specific program areas to help meet some of the industry’s current needs.

Determining expected energy production and related costs over the life of a system is one such need that Sandia is addressing. Over the past two years, Sandia’s PV team has developed a suite of reliability tools specific to PV systems, including models, failure assessment tools, and databases of field performance and reliability.

During the workshop, integrators showed particular interest in the model currently under development, which will provide integrators with a design tool to determine what to expect in terms of energy production and related costs over the life of a system installed in a given location, considering weather, performance, and reliability of each component type. That information will provide integrators with a range and an idea of how many kilowatt-hours will be generated over the systems lifetime, which companies seeking funding from bankers and investors can use.

“The reliability tool suite will help investors understand what the return on their investment will be,” Jennifer says. “In turn, we expect to see increased funding for photovoltaic power sources.”

  The team is looking forward to hosting another workshop within the next year; the last time Sandia was involved in bringing integrators together in a forum was in the late 1990s.

“This was long overdue,” Michael says. “The US research and development strategy has long focused on developing new PV module technologies and improving efficiencies. However, the technology does not get deployed until the system does, so it’s imperative that the system functions well as a whole. We’re pleased to provide our systems R&D expertise to help advance this industry.”