Work Plan

Task 27 Work Plan

t27_New.jpgThere are two primary goals for the work done under IEA Wind TCP Task 27:

  • Conducting global, shared research to better understand technical parameters of small turbines within IEC 61400-2
  • Publishing the results of these research findings in a useful, practical guide on micro-siting small wind turbines

Task 27’s work required analyses of existing 3-D wind resource data and collection of new 3-D data, combined with analyses and CFD models to help analyze 3-D turbulent inflow and directional variability. Some of the new data measurements have been validated with CFD, and other data measurements have been used to inform small wind turbine performance predictions and models.


Historically, Task 27 has held back-to-back meetings with IEC Maintenance Team 2, a group of experts re-writing IEC 61400-2. Participants discussed IEC standard requirements for turbulence parameters, turbulence models, and sensitive load cases, which may differ from the current requirements that were historically taken from the large wind IEC standard 61400-1.

While there are a number of existing 3-D wind resource data sources, no ongoing research exists to help experts write better turbulence requirements. On some occasions, small commercial wind turbine projects have produced less electricity than expected when compared to production estimates based on independent testing results. This inconsistency has led to confusion among consumers regarding actual turbine production.

This lack of data and inconsistent production are linked to the turbulent environment where small wind turbines are installed. Highly turbulent sites where small wind turbine consumers live and work may have less efficient turbine production than estimated. Because of this, experts recognized the need for global, shared research on turbulence parameters for high turbulence cases.


IEC 61400-2 Maintenance Team 2 is scheduled to revise the standard in 2018. All of Task 27 participant’s case studies, technical results, papers and presentations can be used as a basis for the next revision. Having an international standard that better reflects typical consumer sited small wind turbines will help ensure that the technical design requirements meet market demands.

In 2017, Task 27 plans to:

  • Compile country case studies documenting of all the research, modeling and testing efforts conducted within Task 27
  • Discuss and complete the list of technical considerations for the future IEC 61400-2 standard, fourth revision
  • Draft an IEA Wind TCP Recommended Practices on micrositing of small wind turbines, a practical, useful guide on the importance of good micro-siting for small wind turbines, guidelines for good micro-siting, and models and tools to more accurately predict wind turbine performance based on detailed site input

These activities will be concluded at the end of 2018 and be shared with IEC 61400-2 fourth revision experts.