The current implementation of REopt in the SAM user interface uses the REopt web API at https://developer.nrel.gov/docs/energy-optimization/reopt/.

REopt has a new Julia package under development: https://github.com/NREL/REopt.jl.

When the Julia package is ready, it would be possible for SAM to run REopt locally. This would potentially be faster and more reliable than the web API calls.

Also consider new version of REopt and "stable" endpoint.