The small southeast Iowa town of New London (pop.1793), started construction of a 1.5 MW wind turbine on Oct. 24, 2011. We were visiting a local farm family Sunday and were treated to a visit to the site. I snapped a few pictures to document the size and scope of the equipment needed for such an installation. The ladder into a doorway on the left side of the tower gives a sense of size. |
Allow me to promote wind energy production in the state of Iowa. The state ranks near the top in all types of rankings according to this article by Midwest Energy News.
Join me below the squiggle for more details.
The wind turbine generator below is made by the VENSYS company in Germany. Their website offers a video and details about the company. They advertise their gearless generator as more reliable and requiring less maintenance. The blades and tower are made in the United States. Siemens has a blade manufacturing plant in nearby Ft. Madison, IA. I do not know if the blades for this facility come from there.
The gearless VENSYS 1.5 MW requires fewer components, reduces wear and brings higher energy yields. It is the most popular gearless wind turbine in the 1.5 MW class at present – with over 3,000 turbines installed worldwide.
One aspect of the blades that struck me was how curved they are. They have an attack curve into the wind visible in this image.
The tower height is 280 feet. The service crane stands the same height in order to be able to lift the blade assembly for attachment to the generator.
Technical data from the VENSYS pdf. The turbine cut-in speed is with a wind of 3 m/s, nearly 7 mph. The rated speed is 12.5 m/s. Cut-out takes place at 22 m/s. That is equivalent to 49 mph. The diameter of the blade rotor is 82.34 m. The blades sweep out an area of 5,325 square meters. The operating range is between 9 and 17.3 rpm. Speed control is by microprocessor done remotely from Germany. The rated voltage output is 690 V. |
An interesting and costly aspect of the construction involves the crane. We were told it took 15 or so semi-trailer flatbeds to haul all of the components of the enormous crane to the site. It could only be assembled on-site. I was told the cost of the crane rental was $1500/hour. This image shows the relative scale of the base of the crane by noting the door to the cab. The entire assembly rested on a layer of 12" thick wooden planks on top of a gravel bed.
Looking upward, it reached the 280' height. On top was a wind anemometer and vane to monitor speed and direction. Lifting the blade assembly for attachment to the generator is a delicate operation.
Here is a short video with a similar crane in action at a turbine site in Wisconsin.
The town of New London expects a payback on this investment within 20 years, according to my host. Currently, they purchase electric energy from the utility company in the area. Because of power failures from storms, etc, they have 4 diesel engine electric generators that operate as needed during those emergencies. Shermco industries from Texas is installing the turbine. It will also maintain, repair, and service the facility. According to a press release for the project...
The new wind turbine facility will generate enough electricity to power 350 homes. With a Department of Energy study forecasting that electricity prices will increase 50% over the next several years, New London Municipal Utilities decided this would be a good time to install the turbine. Wind energy is clean, unlimited and reduces the need to rely on foreign fuel sources. Using power from the turbine will also annually offset nearly 3,000 tons of carbon emissions that would have been released into the environment by fossil fuel generation facilities.
As we approached the construction site, we notice the police car parked across the drive. It appeared someone was sitting in it to monitor the site. On closer approach, it turned out to be a fake. Instead of a policeman, there was a traffic cone on the seat with a cap sitting on top. From a distance, it appeared to be a person.
I hope this project turns out to be successful for the New London community. This rural Iowa community is like others. It is very conservative leaning. But, given the facts of rising energy costs and the need for electricity, they chose to invest heavily in this technology. Many of the citizens are farmers and good stewards of the land. They know the importance of caring for their resources in order to extend their lifetime. I applaud their forward thinking attitude. |