Photo of a man in an orange vest and hard hat performing maintenance on a PV array.

The National Park Service sought FEMP technical assistance for guidance on how to modernize the off-grid solar PV system at the Natural Bridges National Monument in Utah.

Photo by Andrew Kuhn, National Park Service.

The National Park Service's Natural Bridges National Monument in Utah has operated as an off-grid system since the 1980s. This system, which includes solar photovoltaics (PV), battery storage, and diesel generators, serves as the sole source of electricity for the park's operations. Over two decades ago, NREL researchers provided technical assistance for the development of a solar PV system within this off-grid setup. While still operable, certain components of that PV system are past their useful life, such as the PV modules exhibiting issues like delamination. The National Park Service sought FEMP technical assistance for guidance on how to modernize the system.

The technical assistance team conducted an on-site assessment of the system and made the following recommendations: 

  • Replacement required: PV modules, inverters, multi-cluster box, and PV DC junction box
  • In good condition for continued use: existing wiring, racking, and foundation
  • Modifications to the existing setup: adjusting PV tilt angle to reduce shading
  • New components to consider adding: a monitoring and control station

Additionally, the team offered insights into the considerations for incorporating additional distributed energy assets should more electricity loads be added. These recommendations are currently being used to inform future project planning on updates needed for the PV system.

Lessons Learned

  • FEMP Technical Assistance can provide agencies support not only in the distributed energy resource (DER) feasibility assessment phase but also as components of DER assets approach end of useful life. Agencies can seek assistance with identifying ways to prolong DER life to maximize their value.
  • This technical assistance engagement showcases the ongoing relationship between FEMP, federal agencies, and national laboratories to provide technical support throughout DER asset lifecycles in the federal sector.