Across much of the nation, and particularly the northern quadrant, wind seems to be perpetually present, blowing dust into our homes and barbecue smoke into our eyes.
In fact, as this test proves, wind is much more intermittent – even downright absent – than our senses would have us believe.
To prove this, Inland Power – the largest electric cooperative in Washington – installed solar panels and a 35-foot wind turbine, each system costing about $22,000 and each delivering approximately the same amount of electricity under optimum conditions. Initially, the experiment was to help customers decide which renewable energy system would serve them better.
According to Inland Power engineers, the solar panels delivered almost five times as much electricity as the wind turbine. Why?
Not only is wind more erratic than sunshine, but wind turbines are designed to “kick in” at a certain lower limit. For many, this is a wind speed of between 3 and 12 miles per hour.
In addition, while very strong sunlight simply improves a solar panel’s performance, very high winds – rather than generating more energy – cause wind turbines to cut out to prevent damage to the hub and/or gearbox.
Surprisingly, even very short winter days showed solar delivering more bang for the buck than wind turbines.
Wind’s only advantage? At this point, and for a little while longer, wind is cheaper. However, as solar cell efficiencies improve, and manufacturing techniques drive down the cost of panels, solar may soon become the clear winner.
Of course, we knew that all along.