Vectran Fiber helps energy-generating aerial wind turbine lift off
A liquid crystal polymer fiber that has landed on planet Mars is now being used closer to earth for its high performance in another type of MARS application – the Magenn Air Rotor System.
Kuraray America's Vectran fiber is being used in a cable tether that is suspending a new type of alternative energy solution – a lighter-than-air tethered wind turbine that rotates about a horizontal axis in response to wind, generating electrical energy.
Vectran is the core of a braided cable tether that is wrapped with copper that can carry electrical currents. The tether is part of a sophisticated connection system that hooks the generators on each side of the floating turbine 1,000 feet up in the air – where the winds blow steadily and reliably – to the ground below and transfers electricity that can be used immediately or stored in batteries.
The fiber's high strength yet light weight made it ideal for this new rotating aircraft that generates electricity, according to the developers of the unique hybrid tether that combines fiber and metal into one system that can hold up to 20,000 pounds.
Fiber Meets Specials Specs
Vectran fiber met the specific requirements sought by Atkins & Pearce (A&P), a 200-year-old leading producer of engineered textiles with an expertise in braids and fibers.
A&P collaborated with Canada-based Magenn Power on developing the prototype system for MARS over the past three years, which was successfully launched in April 2008 and is now being tested.
“We were looking for a material with high strength that also had to be lightweight so the helium could lift the balloon off the ground,” said Jeramie Lawson with A&P's new product development team.
“Steel cables would be too heavy,” he said. “We also needed a material with low elongation, even when carrying a large tensile load, and not stretch. We also were faced with the challenge of balancing the elongation of the Vectran fiber and copper.”
A&P selected Vectran from a myriad of other high-performance aramid fibers.
“We have the world's largest inventory of raw fibers,” Lawson said. “Vectran has a great strength-to-weight ratio. We knew from our experiences with Vectran that it would work because of its high strength, low weight, abrasion resistance when other yarns move against it, as well as its temperature and chemical stability.”
Aluminum end fittings were designed by Applied Fiber to properly connect the Vectran cable segments to the wind turbine.
These resin-infused terminations at the ends of the rope allowed the segments to be threaded directly into a splitter box to secure the balloon, said Paul Badeau, vice president of business development of Applied Fiber, a pioneering developer of an advanced composite termination technology for synthetic fiber cables that provided the end point terminations.
“Vectran's high strength combined with the Applied Fiber terminations allowed a secure, light weight connection from the cable to the blimp,” said Badeau. “If the fibers stretch, the conductors within the cables can break. Vectran is a zero creep fiber that lends itself well to a balloon tether and this application.”