Solar Forecast Arbiter Blog

Test Trial 3

Will Holmgren Oct 29, 2020

Test Trial 3 will test day ahead and hour ahead forecasts for AC power, mean SURFRAD GHI, and probabilistic forecasts of GHI. This trial will run on Solar Forecast Arbiter version 1.0rc4. We ask that users not upload real forecasts for this test of the trial system. Rather, users should...

Release Candidate

Will Holmgren Jul 08, 2020

The Solar Forecast Arbiter is out of beta and onto the “release candidate” phase! This means that all of the important platform features are implemented and all known critical bugs are eliminated. A 1.0 final version will follow in the next few months. If you plan to use 1.0 final...

First Trial Data Uploads

Tony Lorenzo May 18, 2020

This post describes the first test trial of the Solar Forecast Arbiter framework, and a script that participants can uses to generate and post random forecasts for the trial. Read about the full testing plans in the Trials Testing blog post. To set up a trial, the framework administrators perform...

Trials Testing

Will Holmgren Feb 12, 2020

This post may be updated based on stakeholder feedback. The Solar Forecast Arbiter now supports anonymous operational forecast trials. The team has run a series of internal tests of this feature. Because of the importance of this feature, we’re requesting that forecast users and forecast vendors help us test the...

Baby Steps

Will Holmgren Feb 10, 2020

Are you curious about the Solar Forecast Arbiter but you don’t want to commit or you’re not sure how to get started? This is for you! First, we totally understand your hesitation. Full use of the Solar Forecast Arbiter requires a lot of trust in the technical aspects of the...

Anonymous Data

Will Holmgren Sep 30, 2019

Several stakeholders have expressed interest in publicly sharing anonymous power plant data in the Solar Forecast Arbiter. While the Arbiter does not explicitly support anonymous data exchange, we can provide some recommendations for how to use the Arbiter’s features to accomplish this goal. Please keep in mind that these are...

Data Exchange Revisions

Will Holmgren Mar 26, 2019

Thanks to all of the stakeholders that provided feedback on the data exchange proposals. This blog post describes: Revised missing, irregular, and regular data policies New probabilistic forecast formats Miscellaneous changes to data exchange policies The revised versions of the dashboard documentation, API, and data model are now available:

Scratch The Surface Of Github

Will Holmgren Jan 29, 2019

If you’re reading this, you should take 5 minutes to complete a handful of intro GitHub tasks. It’s free and it’s easy. First, sign up for GitHub at If asked, choose the free plan. Why? Creating a GitHub account will give you much more visibility in project development (which...

January 2019 Updates

Will Holmgren Jan 29, 2019

A quick summary of activities on the Solar Forecast Arbiter project so far: Stakeholder Engagement Workshop. The team held the first Stakeholder Engagement Workshop in June 2018 immediately following the ESIG Forecasting Workshop in St. Paul. More than 40 stakeholders participated in lively discussions and provided crucial guidance to the...

Solar Forecast Arbiter Blog

Will Holmgren Nov 02, 2018

The goal of this blog is to provide a place for the Solar Forecast Arbiter team to communicate project updates and discuss related material in an informal way. We hope that it gives the solar forecast community some additional insight into our thinking. We welcome your suggestions for topics! Please...