Polar power

Eight wind turbines, manufactured by a Scottish company, are now powering the first zero-emission research station in the Antarctic.

The Princess Elisabeth Station, located in an eastern province of the polar continent, is housing a team of scientists studying the effects of climate change.

The station is the first polar research base to operate entirely on renewable energy. Other stations rely on diesel generators because no wind turbines, until now, were believed to be robust enough to survive polar temperatures and winds.

The 6kW wind turbines from Proven Energy are expected to withstand temperatures of -60°C and wind gusts of more than 200mph, while continually providing 230V electricity for the research station’s heating, computers, lights and scientific instruments. It is claimed that the electricity generated will be the highest output of any small wind power system in the world.

Mark Connolly, a spokesman for Proven Energy, said the turbines are designed to bend forward during strong wind gusts.

The turbine’s rotor includes three blades each with two spring-loaded hinges at the blade root. This assembly, known as a Zebedee hinge, comprises an inner hinge angled at 90° and an outer hinge angled at 45°. When the winds get stronger, the blades are thrown outwards by centrifugal force and the Zebedee hinges flex. The flex action twists the blades and reduces their aerodynamic efficiency.

All of this limits the power of the rotor so it is designed to run up to a certain speed and then no faster. Proven Energy claim this will allow its turbines to generate close to the rated output of electricity even in storm force winds.

‘Other wind turbines have a generator in them that have to be cut off in high winds,’ he said. ‘Ours don’t have a generator so we can continue to produce power.’

The turbines were originally designed and developed by Proven Energy founder Gordon Proven a couple of decades ago to withstand the high winds of Scotland. The Proven Energy team has slightly altered their design to make sure the turbines could endure more extreme weather.

The original turbine blades were made of the thermoplastic polymer polypropylene, but Connolly said Proven Energy are now using a glass composite material that sells under the brand name Twintex.

‘The nature of polypropylene is nothing sticks to it,’ he said. ‘The glass composite allows the properties of polypropylene with the strength of glass fibre.’

When the turbines were used only in Scotland, Connolly said the turbines would never experience wind gusts above 100mph. Now, in the Antarctic, the turbines will be faced with constant high winds that average about 53mph and gusts of more than 200mph.

Connolly said Proven Energy was chosen in 2007 for the Princess Elisabeth Station project after the successful installations of its turbines in other locations battered by extreme weather over the last several years.

‘The turbines had survived a typhoon in Japan and ice storms in Slovenia,’ he said. ‘That’s the reason [Princess Elisabeth] contacted us.’

The station has been designed to reduce the ecological footprint of research being conducted in Antarctica. The concept was set forth by the international Antarctic Treaty, which was enacted in 1961.

The turbines are the main power provider at the station but wind is not the only renewable energy source being exploited there.

The roof of the station is covered with photovoltaic panels to provide extra electrical needs and solar thermal panels melt snow for the scientist’s water supply.