Ships with rally-car suspension, seahorse-like tails or featuring their own harbours have been unveiled in the fight against a major obstacle to the UK's plans for a clean energy future: seasickness.

New technology is needed to defeat this oldest of seafaring problems, and 13 inventive ideas, including a ship steadied by a huge deep keel and another with a giant robotic arm, have shared a £1m development prize from the Carbon Trust.

The UK plans to erect 6,000 giant offshore wind turbines by 2020 to provide 25% of the country's electricity, but the structures have to be installed in far rougher and more remote waters than the 487 so far erected.

Thousands of technicians and engineers based at sea will be needed for maintenance and repairs, and getting them safely aboard the turbines in heavy swells is one of the toughest challenges currently facing the offshore industry.

"It's not the turbines and it's not the foundations that are the big problems, it's the weather," said Dave Armstrong, whose company North Sea Logistics runs 22 turbine-support ships, and whose hinged gangplank is one of the winning ideas. "If the weather is too rough you can't get the guys out. And the last thing you want is the guy being sick onboard as he's no good to anyone after that, believe me."

Benjamin Sykes, director of innovation at the Carbon Trust and offshore oil industry veteran, agreed. "You have to be a hundred per cent. Seasickness is a real challenge for work that requires precision, complexity and involves heavy machinery: it's not to be underestimated."

The Carbon Trust estimates that millions of journeys will be required to build and maintain the future offshore turbine fleet over its 25-year lifespan. The next turbines will be built up to 300km from shore and stormy seas big enough to halt work with current equipment occur on about 155 days a year, when waves top five feet.

But the new technologies must deliver workers safely and in a fit state in even higher, 10ft waves, cutting lost days to less than 65 a year. Sykes said that will cut turbine downtime, meaning billions of pounds in extra revenue.

One winner, the Australian-designed Nauti-craft, smooths the ride across choppy waters using four hulls connected to the main deck with a hydraulic suspension system (see video above) adapted from rally championship-winning cars. Another ship, called TransSpar and designed by Canada's Extreme Ocean Innovation, has a huge, deep keel for stability, giving it the shape of a seahorse, while a third is an adaptation of a Norwegian Navy minesweeping hovercraft.

Once at the base of the turbine, engineers have to get on to it, even in high seas. Armstrong's idea converts a long section of the deck of a ship into gangway, which attaches to the turbine and remains steady while the boat bobs up and down in the waves. Another idea to solve this problem is a large robot arm from German company Momac (see video below) which uses sensors to keep the arm steady as it places the worker on to the turbine.

"This is technology transfer from the car industry, and not as expensive as you might think," said Jan Matthiesen, offshore technology acceleration manager at the Carbon Trust. "It is light because it it electric rather than hydraulic, and it also moves fast." He said a turbine has to be visited by a team twice a year, for maintenance such as changing the oil in the gearbox, in addition to any visits for repairs.

A third category in the competition was for mother ships to provide a floating home for workers, with multiple daughter ships to ferry them to each turbine. Two winners have open sterns, forming a harbour within the ship up to 85m long into which the daughter ships would sail, sheltered from the elements.

"You will have an offshore community living out in the ocean, just as you do now with the oil industry," MatthiesenSykes says helicopters are not an attractive alternative. "The oil industry is moving away from helicopters for in-field operations because of safety concerns and, in any case, being winched on to the top of a 100m turbine in a gale is not an attractive proposition."

The winners, chosen from 450 entries, get up to £100,000 for nine months of development. The most promising inventions will then be given further funding by the Carbon Trust and its partners, including E.ON, RWE Innogy, SSE Renewables and Dong Energy. The trust is also helping to develop the turbulence-minimising layouts for windfarms with thousands of turbines, as well as new foundation designs.

The Trust's efforts are backed by the government. The energy and climate change minister, Greg Barker, said: "The UK is leading the world in offshore wind power generation, which is creating a huge market here in design, innovation and new technology. These projects represent some of the best ideas to overcome the challenges of working in deeper water."

Armstrong believes the ocean itself is the greatest obstacle of all: "What we do, putting people on the turbines, is the most challenging job in the whole offshore industry."