Small wind / Buyer questions
Energy and economics
Does historical wind evidence guarantee the same resource throughout a project lifetime?
The short answer
Historical observations provide evidence about the conditions recorded or inferred for a defined period. They do not guarantee identical wind throughout a project's life. Long-term interpretation should consider record quality, representativeness and uncertainty, while clearly distinguishing historical evidence from any scenario about future conditions.
Describe the historical baseline precisely
Record the source years, measurement or modelling method, site transfer and configuration history. A long dataset can still contain exposure changes, gaps or processing differences. Its length alone does not establish a homogeneous reference for the proposed tower.
Explain whether the baseline is an observed average, a corrected long-term estimate or a representative model year. Those products answer related but different questions.
Avoid an automatic certainty improvement
More years can improve context, but year-to-year persistence and systematic assumptions can affect the uncertainty. Do not assume every year is an independent draw or that all uncertainty vanishes as the record length grows.
If future climate scenarios are considered, identify their source, purpose and limits separately. They should not be presented as a precise local wind forecast unless that claim is supported by the underlying method and evidence.
Use robust project scenarios
Test whether the project remains acceptable under credible resource variations and practical operating assumptions. The purpose is to identify sensitivity and resilience of the decision, not to predict one exact sequence of future years.
The handover should state the historical basis, uncertainty treatment and review triggers for updated evidence. This allows the buyer to use the best available resource information while avoiding a lifetime generation claim derived solely from a historical map, a short campaign or an apparently stable long-term average.
Sources
- Peer-reviewed study archived by NOAA: record length and persistence in wind-resource uncertainty
- NREL wind-resource assessment report: measurement analysis and long-term correlation
Examples are illustrative. Confirm product-specific performance, compatibility and supply scope in the applicable documents.