Introduction to a New Standard - IEC 61400-15 Assessment of site specific wind conditions for wind power stations - Progress Update for Offshore

Selena Farris2, Andrew Henderson 1, Richard Whiting3, Jason Fields4, Bob Sherwin5
1DONG Energy Windpower, London, UK, 2Natural Power, Scotland, UK, 3Everoze, Bristol, UK, 4NREL, Colorado, USA, 5EAPC Wind, Vermont, USA


Introduction and overview of the "IEC 61400-15: Assessment of Wind Resource, Energy Yield and site suitability input conditions for wind power plants" standard.

The scope of this standard is to define a framework for assessment and reporting of the wind resource, energy yield and site suitability input conditions for both onshore and offshore wind power plants.

The framework will be defined such that applicable national norms are considered and industry best practices are utilized.

This standard is framed to complement and support the scope of related IEC 61400 series standards by defining environmental input conditions. It is not intended to supersede the design and suitability requirements presented in those standards.


This scope includes:

1. Definition, measurement, and prediction of the long-term meteorological and wind flow characteristics at the site

2. Integration of the long-term meteorological and wind flow characteristics with wind turbine and balance of plant characteristics to predict net energy yield

3. Characterizing environmental extremes and other relevant plant design drivers

4. Assessing the uncertainty associated with each of these steps

5. Addressing documentation and reporting requirements to help ensure the traceability of the assessment processes


Present an introduction and overview to the forthcoming IEC standard 61400-15, in particular focusing on the aspects most relevant to offshore wind energy, which is the determination of the uncertainty in energy yield estimate.


The uncertainty in the energy yield production is arguably the key risk component, both onshore and offshore, for well-design and well-managed windfarms.  This aim of this initiative is to increase understanding and confidence in the estimation and assessment of this risk, for the benefit of both internal players as well as external investors.