Friday I had an opportunity to visit the Papalote Creek Wind Farm near Corpus Christi in South Texas. Owned and operated by E.On Climate & Renewables North America, the farm consists of 196 turbines across an expansive area of cotton and grain farmland. Wind turbines seem to be a polarized form of renewable electricity: people either think they are beautiful or hideous. The Papalote Creek site sits just a few miles from the Gulf of Mexico in between the towns of Sinton and Taft, two cozy farm communities of a few thousand people. I have to say, it's a perfect location. Not only does the area receive a perpetual offshore breeze, but the windmills themselves appear to belong there, at least in my opinion. Here are a few of the highlights from the tour:Vestas Wind Turbine
The development effort that goes into a wind farm is daunting. It can take up to seven years to complete negotiations with land owners, usage rights, environmental impact studies, wind studies, lease agreements, insurance issues, and a host of other logistics. That's before a single turbine can even break ground.
Each turbine sits atop a foundation 11 feet think and 60 feet in diameter. That's a lot of concrete. The mast is anchored to the foundation with 11 foot long steel tension bolts.
Papalote Creek is divided into two phases. Phase I contains Vestas turbines rated at 1.65MW with 130 foot blades. Phase II contains Siemens turbines rated at 2.3MW with 165 foot blades.
Once a farm is operational, land owners typically receive a percentage of the revenue as negotiated during development.
There are over 200 circuit miles of underground cabling routing power from the 196 turbines to several on-site interconnect substations. This is where power from the turbines is fed onto the power grid.
Standing at the foot of a wind turbine, you can hear it. At 14 rotations per minute, and three blades per turbine, a blade whips past every 1.4 seconds--and you can hear it cutting through the air with each pass.
Each turbine has on board computers sending real-time data about the turbine's status to control centers via fiber optic linkage.
Atop each nacelle sits a weather station, constantly monitoring weather conditions and turning the nacelle horizontally to face the wind as well as adjusting the pitch of each blade to maximize air flow.
Vestas turbines require preventive maintenance every six months. Four person crews can perform scheduled maintenance in a little over a day, during which time they spend all their time in the nacelle. They also manage all their "business" in the nacelle. All of it.
