Availability and Variability of Potential PV Solar and Wind Power Production in Oklahoma

Wind and solar energy are two renewable energy sources that are abundant in the Great Plains of the United States. Over the past several years there has been a large increase in the number and extent of wind turbines in the Southern Great Plains so that during the spring 15% of the energy generated in the Southwest Power Pool is wind energy. One downside to the increasing wind power contribution to the grid is the increased variability and some increase in uncertainty of the power production. This study uses 5 years of wind and solar radiation data from the Oklahoma Mesonet to investigate the possible advantages to developing photovoltaic solar energy in Oklahoma as a complement to the wind power generation and in relation to high demand days for the state. The production of energy via hypothetical utility-scale projects at sites co-located with key Oklahoma wind power production sites and as distributed roof-top production in the Oklahoma City area are examined. It is found that the projected solar energy production has 45% less short term relative variation than the estimated wind power production at an individual site and the combined production from a combination of 100 MW wind and 30 MW reduces the variation from wind alone about 30%. The reduction in variability is even greater with the distributed power systems with the estimated distributed power having 63% less variability than from a single wind power site. Regarding availability of the resource on high demand days, it is found that the solar energy is quite likely to be available on the key summer critical demand days and more likely to have adequate power production than from an equivalent scale wind power project. Figure: Relative variability in wind power production at Woodward, Oklahoma compared to distributed power production in the Oklahoma City area for July.