Transitioning to a renewables-intensive future, a goal supported by many US states, presents numerous technical challenges. Distributed energy resources (DER), such as solar and wind, generate have variable power outputs that can impact grid performance and complicate utility operations. To enable greater deployment of DER requires an assembly of technical approaches and solutions, ranging from new tools to integrate and control DER to sophisticated resource forecasting.

This project, which was led by Sandia National Laboratories in collaboration with the National Renewable Energy Laboratory and multiple Vermont utilities, has produced a multifaceted approach to the integration of renewables that is comprehensive and replicable. Focused on Vermont, a state that has ambitious goals for the buildout of renewables (90 percent of the energy delivered, by 2050), the approach includes:

  • Modeling tools that identify the optimal placement of DER within a distribution network
  • Advanced control strategies for better managing the imbalance between load and generation
  • Improvements to weather forecasting programs to enable more efficient utilization of power from renewables.

Overall, the technologies and tools developed through this work represents a significant technical step forward, and make it feasible for utilities across the country to mitigate the impacts of intermittent renewables at much higher penetration levels, while increasing power system reliability. This work has been described by external reviewers as “superb” and “a very impressive effort with relevant results.” Specific outcomes include:

  • Modeling of multiple distribution feeders for two utilities that resulted in the ability to increase PV capacity by 85%, without adverse operational impacts.
  • Advanced analysis and visualization of distribution feeders to determine their dynamic hosting capacity. The analysis methods help maintain grid performance and reliability during rapid shifts in power output. They also support siting decisions to minimize the impact of new DER on the network and utilize distributed storage for mitigation of impacts while optimizing it’s use in peak shaving.
  • Improvements to existing solar forecasting tools that include accounting for total PV capacity, the design of utility-scale PV systems and clear vs cloudy days.

Results from this project were achieved through the Grid Modernization Laboratory Consortium, a strategic partnership between the Energy Department and the national laboratories to bring together leading experts, technologies, and resources to collaborate on the goal of modernizing the nation’s grid. The GMLC was created to enhance lab coordination and collaboration under the U.S. Department of Energy Grid Modernization Initiative. The Grid Modernization Initiative (GMI) supports stakeholders by accelerating the development of technology, modeling analysis, tools, and frameworks to help enable grid modernization adoption.