ENC Features
11:51 am
Fri March 21, 2014

NC Scientists Study Offshore Wind Energy Potential

Coastal scientists are hoping to deploy two buoys in April to explore wind energy potential off the coast of North Carolina.  

Credit UNC Institute of Marine Sciences

  It was the winds of coastal North Carolina that propelled Orville and Wilbur Wright to first in flight more than 110 years ago.  Soon, scientists will launch a one year study to determine if those same coastal winds can be used to power homes and businesses.  The University of North Carolina at Chapel Hill will deploy two – 3,000 lb. buoys to collect information on water and atmospheric conditions in the Atlantic.   Professor of Marine Sciences Harvey Seim says they’ll use the information to help identify viable lease block locations for offshore wind farms.

 “The intent here is to take a closer look at what the offshore wind energy resource is like and to carefully document its structure to help where and where not to consider deployment of offshore wind turbines.”

In 2008, the North Carolina State Legislature requested that a study be conducted to look at the viability of offshore wind energy in our state. 

“The University played a big role in putting together a report for the state at that time over the next year.  And we found that there was reason to be encouraged that offshore wind energy might be feasible off of North Carolina.”

Seim says there has been a series of follow up projects conducted since the study, the most recent will be the placement of the two buoys 20 miles off the coast.  Below the surface of the water is a large, donut shaped flotation collar about 6 to 7 feet in diameter.  The visible section consists of a 12 foot super structure equipped with high-tech meteorological instruments.

Credit UNC Institute of Marine Sciences

  “On the super structure are a number of sensors to measure properties of the atmosphere, the main one being the wind speed and direction.  We have a couple of anemometers, redundant, so we can make sure we’re getting the right measurements.  Air temperature, air humidity, air pressure, rainfall, things that tell us about how cloudy it is.  And in addition, a camera that will take a snap shot of the sea surface conditions every hour.”

Just below the water and at a depth of 50 feet, special instruments will record the ocean’s temperature and salinity.  The two buoys will be anchored to the seafloor about 80 miles apart.  One will be located north of Cape Hatteras and the other off Ocracoke Island.  Seim says the buoys will be placed in areas where there’s a lack of data indicating a favorable spot for wind energy development.

“The intent is to try to fill in the holes in the historical database in sites that look like they should be promising based on other data, but we’ve never taken measurements in those particular locations.”

Seim says the areas where they are conducting their research will be in non-conflict areas, which are places that don’t disrupt military, fishing, and ecological activities.  The purpose of the research project will focus mainly on collecting information about wind speed and direction.  Seim says they’ll study how the proximity of the Gulf Stream to the continental shelf creates a seemingly favorable environment for wind energy facilities.

“This is the Gulf Streams closest approach to the continent anywhere along the eastern sea board except for Florida. And when it comes close to the land, it essentially serves as an energy source and helps pump up the wind fields, we know that’s what happens during the wintertime and spinning up strong storms right off of our coast.”

Credit UNC Institute of Marine Sciences

  The buoys are equipped with satellite communications, which will transmit data back to shore every hour.  According to Seim, the data will be available to the public, as well as local and commercial mariners, divers, weathermen, and scientists.  He says the National Oceanic and Atmospheric Administration will be the primary receiver of the data, and will help distribute the information globally.

“The data from the buoys will flow into the National Weather Service’s model systems and help with forecasting, we’ll also be hosting our own website to present the data to people as well.”

The original buoys were purchased nearly a decade ago.  After an extensive 100,000 dollar retrofit, the pair of buoys were deployed off the coast in 2011.  But before the research could be completed, the buoys were severely damaged either intentionally or by accident.  Over 200-thousand dollars in repairs have been made, and the buoys are set to be deployed next month. Seim is hoping to alert mariners to be on the lookout for the buoys and any suspicious activity.

“The buoys are marked with their identification numbers from NOAA, these NDBC numbers, and they have a website on them that’s fairly easy to access that you could just go in there and let us know if you think there’s something that’s not looking right. We’d also like to ask that people don’t tie off to the buoys.  They’re big and robust, but the instruments themselves are fairly delicate so if you try to throw a line on them, you might damage some of the equipment.”

Credit UNC Institute of Marine Sciences

  The Monitor National Marine Sanctuary vessel was set to deploy the buoys earlier this month, but a critical component failure will keep it in harbor until next week.  When the buoys are deployed, they will spend a year in the Atlantic collecting data.  Seim is hoping the project will receive more funding and can be extended so they’re able to document atmospheric and ocean conditions over a longer period of time.  You can see pictures of the research buoys at our website, publicradioeast.org.  I’m Jared Brumbaugh. 

For more information:

climate.unc.edu/CoastalWind - Original UNC offshore wind energy feasibility study  - the full feasibility study generated by UNC for the state legislature

ndbc.noaa.gov - National Data Buoy Center -  the federal government site where the buoy data will be available to the public in a tabular format, along with many other observing platforms around the country

nccoos.org/platforms  -  the website maintained by Seim's group at UNC that makes the buoy observations available in a graphical format.

The Institute of Marine Sciences in Morehead City, an off-campus research and education center of UNC-Chapel Hill, provided help with outfitting the buoys. YSI Integrated Systems and Services installed the electronics for the buoy instrumentation. The UNC Coastal Studies Institute (UNC-CSI), an inter-university research institute located on Roanoke Island, is partnering with marine sciences on the deployment and maintenance operations. Several local companies in Morehead City also helped to make the buoys seaworthy.