WIND FARM COMPUTER DESIGNER

Designing wind farms for max output
April 11, 2011 (WindPower Engineering)

"Designing a wind farm requires…[maximizing] energy capture while minimizing wind loads on turbines, balance-of-plant costs, and maintaining all setback and avoidance criteria. This complicated task is most easily accomplished with assistance from specialized computer programs developed just for the wind industry. The most widely used program, WindPRO, developed by EMD in Denmark, has been used by the industry with continual improvements for over 20 years. In one computer model it combines all the information needed to efficiently design a wind farm.

"…A designer inputs digital background maps (topographic maps, orthographic imagery, or other graphics) digital elevation data, wind data, surface roughness information, GIS data such as property lines and road-center lines, along with wind-turbine power curves to create a 3D computer model. Changing alterable data allows optimizing…annual energy output, [calculating] noise emissions, shadow flicker, visual impacts…[and provides] photo-simulations…"

WindPRO's image of the factors on the landscape (click to enlarge)

"Turbine arrangement is one of the most important aspects of a wind farm’s design. A small change…can result in a significant difference in annual energy output…[and] translate into hundreds of thousands of dollars per year in revenue…[D]esigners try to take advantage of the natural speed-up effects that occur on hill tops…[and minimize] wake-induced turbulence that results in energy loss (array loss) and increased mechanical loads on the turbines…

"…[D]esigners also must satisfy numerous setback and avoidance constraints, such as a safe distance from public roads and environmentally sensitive areas…[and] minimize the effects of noise emissions and shadow flicker on nearby residences…"

WindPRO's image of what the turbines will look like on the land (click to enlarge)

"…WindPRO easily factors in…[everything] and allows testing over [m]ultiple iterations…[t]o predict a wind farm’s annual energy output…[It predicts] the wind speeds at each turbine throughout the wind farm, as well as array losses…

"Even with all the tools available, it still takes experience, scientific knowledge and engineering judgment to properly design a wind farm and accurately predict an annual energy output. Today’s modern computer tools are helpful, but as with any computer modeling, it is the user’s responsibility to determine the quality and appropriateness of the inputs and the reasonableness and accuracy of the results."