But, even if new turbine designs fail to make it into physical reality, they continue to exist as valuable intellectual property.
The issue of abandoned technology was in the news earlier this year, when UK research body ORE Catapult said it was in discussions to buy Samsung's 7MW turbine. The prototype machine, which has the biggest rotor ever made, was installed at Methil, Scotland. But late last year Samsung announced it was leaving the offshore sector.
Samsung is not the only company to have left a next-generation turbine on the starting blocks. The offshore sector is filled with turbine drawings that were announced with much fanfare and never heard of again, not to mention the many more designs for drivetrains, blades and other components.
There is a big market for orphaned technology. The sellers are often defunct companies whose venture capitalist backers have lost patience. Some of the top-ten OEMs are also believed to be looking at selling off older technology that has fallen out of current product ranges.
To understand the potential minefields, one need only look at GE's patent claims against MHI over its 2.4MW turbine and Enercon's suit against Gamesa and Siemens over storm-control technology. A stash of intellectual property (IP) can potentially bring revenue, and power. In GE's case it backed down, but the battle destroyed the MHI 2.4MW model's potential.
"At one point, there were 230-plus inventions for sale, comprising over 650 globally filed patents. That represents over 2.5% of all the patents in the industry," said Philip Totaro, founder of Totaro Associates. "If one company were to have bought them all, they would be in the top ten in terms of IP asset holdings in the industry."
One recent deal has been for technology developed by US-company Modular Wind Energy (Modwind). It created a modular blade design. The core product was ready, but development stalled as it needed to be tested on a turbine. Although Senvion was lined up as a partner, it never happened and, in 2013, Modwind's venture-capitalist backers lost patience. The IP appeared not to be sold, and the company folded.
But now, that technology is set to appear on a Vestas turbine. The company confirmed to Windpower Monthly it had acquired Modwind's IP but did not disclose the fee.
It is not just components. Nordex and DSME withdrew plans to build offshore machines after they had been drawn up. The Nordex N150 6MW turbine was its first direct-drive machine and had a lower top-head mass than 5MW machines of the time. It was cancelled due to costs in 2012 by then-Nordex CEO Jurgen Zeschky despite the design receiving positive press.
Nordex said it still holds the IP and design rights for the turbine. Although it has received no offers from potential buyers, the spokesperson said: "If there was any interest we would be open to talking (about it)".
Possibly the saddest story surrounds Clipper's Britannia project, an ambitious aim to create a 10MW offshore turbine based on the US company's 2.5MW Liberty turbine. It started a design project to build the blade in the UK that was launched by then-prime minister Gordon Brown in 2010. At the time, at around 150-metres it would have been among the world's largest rotors.
Clipper Marine managing director David Still said the mould was made before Clipper cancelled the project, but a blade was never produced. It is believed the mould was left in the company's former premises in north-east England and may have been destroyed. Clipper's owners Platinum Equity, who acquired the company in 2012, have around 287 globally filed patents but have not entertained any offers, with one believed to be in the seven-figure range. The company appears to have fallen off Platinum's radar.
Other technologies that could be on the market includes Danotek's permanent-magnet-generator technology, including the IP for its 2-7MW units. Another is ChapDrive whose IP was auctioned off two years ago to an unknown buyer. Totaro speculated that one of the ChapDrive properties, an hydraulic drivetrain, could have some overlap with MHI's Artemis drivetrain that was developed for the 7MW SeaAngel.
Enercon's litigation with Siemens, or GE's battle against MHI are one side effect of IP. However, last year it was revealed that Intellectual Ventures, one of the US's leading "patent trolls" — companies that enforce patent rights against alleged infringers and try to collect licensing fees or settlements — had entered the sector.
Patent trolls already cost the tech sector millions. With so much historical overlap between designs and IP available, the appearance of companies like this could cause a bigger issue for wind than the actions of Enercon and GE combined.