The forecasting for renewable energy community has been active since the first wind energy projects were built in Denmark in the 1990s. More than 30 years later, there are still no standards for the inputs into forecasting models and their output, or the evaluation of the performance of renewables generation forecasts. At the end of 2022, the IEA Wind Task 51 "Forecasting for the Weather-driven Energy System" launched its first Recommended Practice on the Implementation of Renewable Energy Forecasting Solutions, an industry guideline on forecast solution selection, forecast evaluation and collection and quality control of forecast input and verification data and instrumentation requirements.

Since then, the IEC Subcommittee 8A on Grid Integration of Renewables Workgroup 2 Renewable Energy Forecasting, has suggested to establish a standard for the evaluation of renewable energy power forecasting, including data preparation, statistics of indicators, evaluation of results and reporting. The standard shall provide a common understanding of the handling and quality of input data to forecasting of renewable energy as well as how data needs to be prepared and used in evaluation of renewable energy generation forecasts. It aims to close a gap in the understanding of forecasting processes on an international level that enables fair competition on forecasting methods and solutions and access to international markets. Both renewable energy power forecasting service providers and users will benefit from a common understanding of methods of evaluating forecasting for specific tasks and areas and enable transparent comparability of solutions.

The two work groups have joined forces on the development of the standard and will present the main features of the first working draft of the standard and discuss with stakeholders, whether the chosen approaches support forecasting service providers, users and research institutions on selecting, verifying and improving existing renewable energy forecasting techniques and its input data quality control.

The presentation will provide an overview to the current state of the draft, it's challenges and unresolved topics. The objective will be to promote a discussion with the stakeholders in the audience of the key issues and alternative approaches to address these issues.