by Willem Post
– is variable, intermittent, has a huge footprint, highly visible, relatively low-cost, if capacity factor is high, i.e., 0.35, or greater.
– requires additional backup power plants (continuously running and on standby) to accommodate varying wind outputs. Such plants consist of intermediate and peaking generating units, such as gas-fired CCGTs and OCGTs, capable of quickly increasing and decreasing their outputs.
– is not dispatchable, because the geographical area of the connected wind facilities may have no or very little wind. However, it has a capacity credit with is defined as the statistical expectation of capacity over time, typically a year; it is relevant to capacity planning. In Texas, ERCOT sets this value at about 8% of the nameplate rating of Texas wind facilities.
– is variable which means it needs more capacity of continously running and standby plants which likely are gas-fired, CO2-producing, OCGTs whose already low efficiency is even lower at low and highly varying outputs, somewhat like a car driven at varying speeds in the city getting less mileage than driven at steadier speeds on the highway. Such inefficient operation of backup plants may actually produce more CO2 than the wind facilities were meant to reduce, i.e., the mix of plants would operate more efficiently without wind power than with it.
– requires additional transmission and distribution system changes and greater grid management efforts.
– has additional costs of about 0.4-0.6 cent per kWh to integrate it into the grid.
– turbines have useful service lives of about 25 years. Significant investments would required at about the 25th year to upgrade the turbines for operating them for another 25 years or, if upgrading is unfeasible, new turbines would need to be installed. Newer nuclear plants have useful service lives of about 60 years, at least 2 times longer than wind turbines.
Willem Post: BSME New Jersey Institute of Technology, MSME Rensselaer Polytechnic Institute, MBA, University of Connecticut. P.E. Connecticut. Consulting Engineer and Project Manager. Performed feasibility studies, wrote master plans, and evaluated designs for air pollution control systems, power plants, and integrated energy systems for campus-style building complexes. Currently specializing in energy efficiency in buildings. He is a founding member of the Coalition for Energy Solutions.