Bear Creek Wind Power Project, Bear Creek, PA (Photo: Community Energy)

Did you know that the United States is now the largest producer of clean renewable electricity from wind turbines? We passed the former leader, Germany, in 2008.  That sounds pretty green.  Of course, the US is a much larger land mass than Germany, so it is not as big of an accomplishment as it might at first sound.  Only about one percent of US electricity comes from wind turbines, but capacity is growing rapidly.  The current economic crunch has been a damper, but then Obama's Economic Stimulus Plan will help.

The US has been called the Saudia Arabia of wind because we have rich wind resources.  The wind resources of Texas, Kansas, and North Dakota combined could supply 100% of the US electrical needs.  Offshore wind could also supply all our needs.  Then there are the Great Lakes region and various other locations across the country.  The Department of Energy has a goal of 20% wind energy by the year 2030. Part of the challenge is that we have to build out our electrical grid to get the power from rural windy areas to the population centers.  That will be a topic for another article.

Wind farms have evolved to address a number of issues including bird kills, noise, aesthetics, safety, and geography.

You may have seen wind turbines in Pennsylvania or other parts of the country. I have seen large wind projects on the plains of Canada that are mesmerizing to look at.  But then,  beauty is subjective.

The modern wind turbines use a large monopole with 3 large blades that turn slowly in the wind. The turning blades operate a generator which produces electricity that connects to the grid.  You may have noticed an offering on your PECO electric bill to buy wind power.  You are buying the RECs (Renewable Energy Credits) produced by these wind farms.

By the way, the new design avoids the problems of earlier units that confused birds.  The old units used support cables to hold the towers up and used smaller blades that spun faster and made more noise. The industry has also learned to avoid migratory flight paths. 

To be financially viable, wind farms need to be located where the wind blows often and briskly. There are a number of places throughout our country where wind turbines are financially viable.  However, there are offshore locations as well. The construction is similar to land based wind farms.  The monopole is buried into the ocean floor in shallow water or using something like an oil rig platform in deeper water.  A power cable is buried under the ocean floor to bring the power back to the grid.

In general, offshore wind farms are attractive because the winds are stronger and more consistent than on land.  Our eastern seaboard is especially attractive for two additional reasons.  The waters are shallow, which allows a wind farm to be built far enough off shore that it is very difficult to see it from the shore.  Also, there is a large population living along the eastern seaboard so the transmission distance is short.  It is a perfect combination: shallow water allows cheaper construction in an area with good wind resources located close to the consumers.

The East Coast has a number of offshore wind farms in various stages of development.  For example, Delmarva Power has agreed to a 25 year contract to purchase up to 200 MW of electricity from Bluewater’s planned wind farm 13 miles off the coast of Rehoboth Beach, Delaware.  NIMBY is an issue wind farms initially have to deal with.  NIMBY is short for “Not In My Back Yard”.  Bluewater Wind has information that discusses the aesthetic issues around their development.  They say that on a perfectly clear winter day the turbines will look like a toothpick on the horizon about half as tall as your thumbnail when your arm is extended.  On a hazy summer day you will not be able to see the turbines.  They even have simulated pictures of what the finished project will look like.

New Jersey, New York, and Massachusetts also have discussions about wind farm developments.  The Massachusetts project off of Cape Cod is getting a lot more NIMBY push back from residents.  The Cape Cod project is between 5 and 14 miles from shore so turbines will be more visible from some shore locations, depending on weather conditions.

On the West Coast, offshore wind farms are not so easy to build.  The Pacific Ocean gets deep very quickly, so it is not feasible to attach wind turbines to the ocean floor.  Some creative people came up with the idea of building floating wind farms! I find it hard to imagine that you can build a floating platform that is stable enough to support a tall tower with blades.  The folks at Principle Power have a plan using a semi-submersible offshore floating base.  They will be built onshore, towed to sea, and anchored.   Hopefully, it will be a successful design.

WindFloat rendering from Principle Power, Inc.