Onshore Wind Companies in Site Studies & Resource Assessment

Site Studies & Resource Assessment in Onshore Wind Energy

The Role of Site Assessment Partners in Wind Projects

In onshore wind energy, Site Studies & Resource Assessment forms the empirical foundation of project feasibility, design, and ultimate bankability. Sourcing accredited meteorological consultants, geotechnical engineers, and surveying firms is the critical first step developers take to de-risk a greenfield site and secure project financing.

The scope of this discipline is highly multidisciplinary. It encompasses the physical measurement of the wind resource, the mathematical modeling of aerodynamic flow over complex terrain, and the subsurface investigation of soil and rock properties.

The physical boundaries span from high-altitude atmospheric boundary layers down to deep subterranean bedrock. The outputs generated by these early-stage studies dictate the macro-level project layout, the exact micro-siting of individual Wind Turbine Generators (WTGs), the structural design of foundations, and the financial baseline for Power Purchase Agreements (PPAs).

Core Assessment Capabilities & Services

When project developers and financial sponsors evaluate site study consultants, they require accredited expertise in the following domains:

• Wind Measurement Campaigns: Design, permitting, and installation of tall meteorological (met) masts. Deployment of remote sensing technologies, including ground-based or nacelle-mounted LiDAR (Light Detection and Ranging) and SoDAR systems to capture shear profile data across the full turbine rotor swept area.
• Wind Flow Modeling & Micro-siting: Utilization of linear flow models (WAsP) or advanced Computational Fluid Dynamics (CFD) for complex terrain. Optimization of WTG coordinates to minimize aerodynamic wake losses and maximize array efficiency using software like WindPRO or OpenWind.
• Energy Yield Assessments (EYA): Rigorous data scrubbing and long-term measure-correlate-predict (MCP) analysis to calculate gross and net energy yields. Delivery of bankable probability exceedance scenarios (P50, P75, P90, P99) required by lenders for debt sizing.
• Geotechnical & Geophysical Surveys: Execution of physical boreholes, Cone Penetration Testing (CPT), and seismic refraction surveys to determine soil bearing capacity, groundwater levels, and dynamic soil stiffness—critical inputs for civil foundation design.
• Topographical Mapping: Aerial drone surveying and terrestrial LiDAR scanning to generate high-resolution Digital Elevation Models (DEMs) for Balance of Plant (BoP) earthworks and access road swept-path analysis.

Integration Across the Project Lifecycle

Site studies are heavily concentrated at the front end of the wind farm lifecycle, acting as the primary input for all subsequent engineering and financial disciplines:

• Greenfield Origination: Initial desktop studies, meso-scale wind mapping, and fatal flaw analyses to identify viable project boundaries before committing heavy development capital.
• Development Phase: Execution of multi-year physical measurement campaigns (typically 1 to 3 years of continuous data). Consultants interface continuously with developers to refine layouts based on emerging environmental or acoustic constraints.
• Pre-Construction & Financial Close: The culminating deliverable is the bankable Energy Yield Assessment (EYA) and the comprehensive Geotechnical Baseline Report. These documents are handed over to Independent Engineers (IEs), EPC contractors, and lenders to underwrite the technical and financial risk of the project.

Industry Standards & Regulatory Compliance

Top-tier resource assessment firms and geotechnical engineers operate under strict, internationally recognized guidelines to ensure data bankability:

• MEASNET: The international measuring network of wind energy institutes, providing the gold standard guidelines for anemometer calibration and evaluation of site-specific wind conditions.
• IEC 61400-15: The overarching international standard for the assessment of site-specific wind conditions and wind energy yield estimation.
• IEC 61400-1: Defines the site condition parameters (extreme wind speeds, turbulence intensity, inflow angles) that must be assessed to ensure the selected WTG class is structurally suitable for the site.
• Eurocode 7 (EN 1997) / ASTM Standards: The governing international and North American standards for geotechnical design, ground investigation, and material testing.
• FGW TR6: Technical guidelines (prominent in European markets) for the determination of wind potential and energy yields.