One size no longer fits all
It is to be expected that not every turbine will be required to work under the same conditions, and in the past, developers have gone with the accepted wisdom that each turbine should be the same across a site, which means an inevitable compromise on the efficiency of energy production - until now. PES speaks to Rubén Martínez Fanals of Alstom about their unique solution...
The nature of wind farm sites means that installed turbines face distinct variations in the conditions under which they operate: different landforms, the presence of vegetation, buildings, etc., bring about a variety of wind conditions (average wind speed, Weibull parameters, turbulence levels, etc.) within the same project. Traditionally, the approach to wind farm development considers the site as a whole, which has meant specifying the best single wind turbine model which fits all positions. Given the wind variations between turbines, this "one size fits all" approach is not able to make optimal use of the wind resource available across the whole site.
Of course, it would be possible to specify individual turbines, each with their own rotor diameter, power output and hub height to optimize the capacity factor of each turbine its own position - this would clearly result in greater efficiency and a reduction of the overall cost of energy is achieved.
However, this solution faces a major disadvantage. The use of different wind turbines within the same site might require that the operation and maintenance of the wind farm has to be individualized for each turbine model. Clearly, the need to tailor maintenance procedures, procure different, possibly non-standardized spare parts or distinct training manuals, etc., will result in higher operational costs of the wind farm which might unbalance or even nullify the benefits gained by the optimization of the site's capacity.
Now, this disadvantage can be overcome by applying a product platform approach, which allows the sharing of superior core designs, proven sub-systems, optimized production processes, common logistics and supply chains within a range of products, to efficiently expand the product offering and serve broader market needs. Alstom is effectively applying this platform strategy to its ECO 100 platform, which allows project developers to select the best wind turbine rotor for the specific wind conditions found in the different positions of the wind farm, and ultimately optimize the capacity factor of the project by up to 10 per cent.