This document outlines guidelines for standardized wave energy resource assessment and defining standard wave climates. It discusses the evolution of wave energy resource assessment methodologies since the 1970s. Specifically, it describes the development of the WERATLAS atlas which provides wave climate statistics for 85 locations in Europe. The document also summarizes a method for obtaining resource statistics at any location based only on the annual mean power level. Finally, it presents guidelines for deriving wave statistics from data and defining parameters for short and long-term wave analysis to standardize wave energy resource characterization.

1. International Conference Ocean Energy OTTI – Abstract
Guidelines for Wave Energy Resource Assessment and
Standard Wave Climate
J.B. Saulnier*, M. Teresa Pontes
INETI, Dept. Renewable Energies, Estrada do Paço do Lumiar, 1649-038 Lisboa, Portugal,
* Corresponding author: telephone: (+ 351) 217 127 190, e-mail: jbaptiste.saulnier@ineti.pt
M. Burger, F. Gardner
Teamwork Technology, Zijdewind, Noord-Holland, The Netherlands
Topic: Wave Energy Resource
Oral Presentation
It can be said a methodology for assessment of wave energy resource started in late 1970´s within
the British Wave Energy Programme and it has been developed as new sources of wave data have
and are becoming available.
Important contributions have been made within the EC R&D Programmes on Wave and Tidal
Energy. Within this project, a review of wave data was made and the basis for a methodology for
resource assessment was proposed. This consisted in developing offshore wave statistics for ocean
basins based on results of wind-wave models after verification against buoy data. After that
nearshore conditions should be computed using shallow water wave propagation models. The first
step of this methodology was implemented within a follow-on EC project where WERATLAS –
European Wave Energy Atlas was developed by seven leading institutions of six European
countries (e.g., Pontes et al, 1995). This open-ocean atlas includes detailed statistics of wave
climate and wave energy parameters in 85 points (41 in North-eastern Atlantic and 44 in the
Mediterranean). Based on the WERATLAS information, a method was developed and implemented
that enables to obtain resource statistics (scatter diagrams of wave height and period) at any point
based on the annual mean power level only (Burger, 2005). This method is summarised in this
paper and tests are presented.
Having in view to standardize wave energy resource characterization, the selected wave climate and
wave power distributions and parameters are presented. In addition to the basic wave height, period
and direction parameters usually considered, other sea-states characteristics that should also be
relevant for the performance of wave energy conversion systems including wave grouping, spectral
width and directional spreading are considered. Wave data sources and types are reviewed.
Guidelines for deriving wave statistics from wave data (measurements and wind-wave model
results) are presented. The usually used wave parameters for short-term analysis (wave height,
period, direction) as well as the most commonly drawn long-term statistics (including uni- and
bivariate distributions, exceedance plots, inter-annual variability) are presented as a step for a
methodology. A wave resource based on high-quality buoy data off the west coast of Portugal is
summarised, having in view to enable benchmarking wave energy devices performance. This work
is being developed within WAVETRAIN, a Marie Curie training network (Saulnier and Pontes,
2006).
Pontes, M.T., G.A. Athanassoulis, S. Barstow, L. Bertotti, L. Cavaleri, B. Holmes, D. Mollison, H.
Oliveira-Pires, “European Atlas of the Wave Energy Resource”, Proceedings of the Second
European Wave Power Conference, Lisbon, p.28-35, 1995.
Burger M.F. (2005) Standardised wave data based on power level, Master thesis report, Delft
University of Technology, Teamwork technology BV, Holland.
Saulnier J.-B.M.G., Pontes M.T. (2006) Guidelines for wave energy resource assessment and
standard wave climate, Deliverable nº4-7a, WAVETRAIN, contract nº MRTN-CT-2004-505166.