All environmentally relevant flows of energy and materials are accounted for in a Life Cycle Assessment (e.g. inputs of electricity, fuels, material resources, and output wastes and emissions to air, water and land). These flows are assessed for all the components and processes that make the entire wind power plant and summarised across the complete life cycle.
The life cycle of the wind power plant is modelled in the Life Cycle Assessment using a modular approach corresponding to the life cycle stages shown in the figure below. This allows the various life cycle stages and various components of the wind power plant to be analysed individually.
Vestas’ wind turbines are designed to meet different functional requirements for both onshore and offshore environments, as well as the wind class for which they are designed to operate. The wind class determines which turbine is suitable for a particular site, and influences the total electricity output of the wind power plant.
When benchmarking an array of wind turbine’s performance it is important that it’s done on an equivalent functional basis, so they can be compared within similar wind classes. There are three wind classes for wind turbines which are defined by an International Electrotechnical Commission standard (IEC), corresponding to high, medium and low wind.
The various Vestas wind turbines have been designed to operate under high, medium or low wind conditions. For each study the specific wind conditions have been selected to evaluate the turbines environmental performance.
In order to assure the rigour of Vestas Life Cycle Assessments and the robustness of the results, all Life Cycle Assessments are conducted in accordance with the ISO standards (ISO 14040/44) for Life Cycle Assessment. Each study has undergone an independent critical review by an expert in the field.