Sparks

Wind in the freezer

 By Robin Wylie

The coldest regions of our planet tend to have both low population density and high wind speeds, and accordingly the capacity for wind power generation in these regions is unusually high. Currently, however, the majority of wind farms lie in the Earth’s temperate regions, leaving the (possibly vast) wind energy potential of colder regions largely untapped. Robin Wylie summarises a recent study into wind power in cold climates, and will also explore the parts of the world where wind power could be harnassed in the future… 

(Cover photo by www.renewablespress.com)

Wind power is on the rise. Over the past two decades total global wind power capacity has doubled on average every three years—soaring from 6 gigawatts (GW) of installed capacity in 1996 to more than 430 GW today. Until now, wind power development has mostly been confined to the world’s temperate regions. But with the right technological adaptations, the colder parts of our planet could be even better places to harness the energy of the wind.

Colder regions tend to be more sparsely populated, making them particularly attractive sites for large-scale wind power development. As wind power development continues to flourish in places like China, Europe and the United States, fewer and fewer temperate sites will become available, perhaps forcing these regions to locate future wind farms in their colder, more northerly regions.

Locating wind power projects in cold regions also makes sense from a physical perspective. Cold air is denser than warm air, so for a given wind speed, cold wind contains more kinetic energy, and can therefore potentially drive wind turbines more efficiently. But there are also significant drawbacks to sub-zero wind power.

CREDIT - GAVIN SCHAEFER

Most of today’s wind turbines are designed to operate optimally in temperatures down to around -20°C (-4°F). But when temperatures drop below that for significant lengths of time, the build-up of ice on turbine blades can hamper their performance, leading to power losses of between 3 and 16 percent per year.

But recent technological improvements could help overcome the problem of turbine icing, potentially facilitating the future development of wind power in Earth’s coldest regions. Siemens has recently begun producing wind turbines with integrated electrical heating elements, while Enercon has developed a turbine which uses percolating hot air within the blades, both of which can offset or eliminate the production losses associated with ice formation.

The use of anti-icing technology is still limited in the wind energy sector. But the development of wind power in cold climates is growing regardless. In 2013, approximately 70 GW of wind energy capacity—or 20 percent of the world total at the time—was located in cold regions (defined as “places where low temperatures and icing events occur which subject wind turbines to stresses outside of their design limits”). Experts predict that a further 50 GW will have been installed by 2017—a rise of over 70 percent in just four years.

about the author
Robin Wylie
Freelance earth/space science journalist. Currently finishing off a PhD in volcanology at University College London.