Page 217 - Wind Energy Handbook

WIND-TURBINE PERFORMANCE MEASUREMENT 191

and covers power performance, acoustics, blade testing, mechanical loads and power
quality. Power performance testing is covered by the published IEC standard 61400-
12 (1998). The IEC standard also exists as a British and European Standard BS EN
61400-12:1998. All national standards bodies have a responsibility which extends to
any significant technology. Accordingly, national standards committees have been
formed in most countries to cover wind energy technology. In many instances these
merely formalize the national participation in international standards formation, and
tend to adopt acceptable international standards as national standards.

CENELEC

CENELEC is a European committee, concerned with electro-technical matters,
which has established a task force to manage the harmonization of safety and
testing standards in support of various European Union Directives. The task force
is presently assessing the adequacy of evolving IEC standards and may, or may not,
issue its own standards relevant to wind turbines in the future.

International Energy Agency (IEA)

In the early days of wind energy, prior to the involvement of the standards
organizations, the IEA took the lead in drawing up recommendations, or informal
codes of practice. The IEA codes of practice have been highly influential, and
covered power performance, acoustics, power quality and fatigue.

MEASNET

Most western European countries have established national wind test sites. There
has been a tradition of close co-operation between these sites and, supported by the
European Commission, many useful documents have been developed by ECWETS
(the European Community Wind Energy Test Station). More recently, the MEAS-
NET network for the promotion of quality, common interpretation and mutual
recognition in testing standards, was created.
MEASNET is a European collaboration of experts concerned with establishing
rigorous standards for all measurement procedures related to wind energy. In
particular, they have drawn up draft guidelines for ‘power performance measure-
ment procedure’. Although heavily reliant on the IEC Standard, they are in some
areas more precise.

4.7 Wind-turbine Performance Measurement

In the final analysis, wind-turbine performance is concerned with the estimation of
long-term energy production expected on a given site. The wind resource is