REopt Lite’s Application Programming Interface Boosts Solar+Storage Analysis Flexibility

June 18, 2018 | Contact media relations

The National Renewable Energy Laboratory (NREL) released an application programming interface (API) for its REopt Lite solar photovoltaics (PV) and battery storage optimization web tool. The API enables streamlined integration with other tools inside and outside NREL, allowing building owners and researchers to evaluate the economics of grid-connected solar PV and battery storage (solar+storage) at multiple commercial sites and perform sensitivity analyses in an efficient manner.

The API opens opportunities for research collaboration and broader market impact, driving solar and storage deployment. Other NREL web tools have seen significant uptake with the release of an API, including the popular NREL PVWatts Calculator, which has an estimated 95% of 39.8 million calls per year accessed via its API.

Using the REopt Lite API, a major U.S. city is considering integrating REopt into its solar map to inform building owners and developers of solar and storage opportunities, and a Midwest utility is exploring using the API to evaluate how adjustments to utility rate tariffs may impact the economics of solar+storage.

REopt Lite makes behind-the-meter economic optimization of solar+storage systems widely available to the public via an easy-to-use web tool. It identifies the optimal PV and battery system sizes and dispatch strategy to minimize the life cycle cost of energy at a specific site and estimates the amount of time a PV and battery system can sustain the site's critical load during a grid outage.

In addition to the API release, REopt Lite developers have added expanded resilience analysis capabilities, a downloadable dispatch strategy, and additional utility rates to the web tool. The REopt development team is working on further capabilities for release later this year, including the integration of a wind model.

REopt Lite is developed with funding from the Department of Energy’s Office of Energy Efficiency and Renewable Energy Federal Energy Management Program, the Solar Energy Technologies Office, and The Kresge Foundation, through Clean Energy Group’s Resilient Power Project.

REopt Lite is a publicly available web version of the more comprehensive REopt model. Learn more about NREL’s REopt analysis services at

Tags: Solar,News,Energy Analysis,Photovoltaics,Energy Systems Integration,Buildings,Partnerships