But as easy-access wind-rich sites continue to be snapped up around the world, developers are increasingly looking to the far north and high-altitude regions — where winds are strong, energy yields are higher due to lower air density, and there are fewer permitting hurdles and local opponents to overcome.
“There has been a lot of talk about the potential of offshore wind power, but the market for cold-climate wind energy is many times greater,” says Tomas Wallenius, chief technology officer at Finnish ice-prevention specialist Wicetec.
Installed wind power in cold-climate regions is expected to reach close to 120GW worldwide by the end of 2017, according to the VTT Technical Research Centre of Finland. By comparison, less than 20GW of offshore wind is expected to be installed by the end of 2017.
“The beauty of this [cold-climate] technology is that you access sites that haven’t been accessed before, because you got too many icing hours during which the turbines normally had to shut down,” says Nils Lehming, cold-climate-technology production manager at German turbine maker Nordex.
“But with an anti-icing system you can de-ice, keep the rotor blade ice-free and let the turbines run, as it is commercially viable to do that now, even in areas such as Lapland.”
In major wind markets such as Canada, Scandinavia and northern China, cold-climate technology is all but essential, while demand is expected to increase in Europe’s Alpine areas, the Baltic states, Mongolia and the mountainous provinces of inland China such as Guizhou, Sichuan and Yunnan.
“Right now, the hottest markets are Finland, Sweden, but also Norway,” Lehming tells Recharge.
In China, curtailment and feed-in-tariff reductions in the northerly wind-rich regions are increasingly driving developers into high-altitude areas further south, says FTI Consulting analyst Feng Zhao.
North America, already a hotbed for cold-climate turbines, is set for further expansion due to the recent production tax credit extension in the US and ambitious new renewables targets in the western Canadian provinces of Alberta and Sasketchewan.
Several turbine makers earn a substantial part of their income from cold-climate turbines. Nordex, which placed an early bet on the technology in the mid-2000s, has sold about 1.5GW of machines into the segment, accounting for about a quarter of its annual revenue. Senvion earns 5-10% of its revenue from cold-climate turbines, while they represent about 10% of the machines sold each year by Enercon. Vestas and Siemens declined to disclose their share of revenue from cold-climate areas, but said they had, to date, sold 5GW and 800MW respectively.
The type of cold-climate adaptations that need to be used will often depend on a project site’s humidity, as well as the temperature, explains Enercon spokesman Felix Rehwald.
The company has vast experience with cold climate technology in Scandinavia and Canada, where in often cold and humid locations rotor blade de-icing systems are likely to be needed.
“Depending on the location, additional yields of 10-20% can be achieved when compared to machines without a de-icing system,” Rehwald says.
In very cold, but dry regions, including inner China and Mongolia (where Enercon does not sell turbines), adaptations such as specialised alloys, special steel for towers or bespoke lubricants can suffice.
Gearboxes must be protected with heating systems in all extremely cold environments, SgurrEnergy consultant Oskari Koljonen points out.
Of course, turbines with built-in cold-climate technology cost more than standard models. Manufacturers are understandably reluctant to reveal the exact mark-up, but Ville Lehtomäki, a senior scientist at VTT, believes the technology will add €30,000-100,000 ($32,500-108,000) to the price of a typical €4.5m 3MW turbine.
So, when does it make commercial sense for a developer to pay extra for cold-climate tech? Nordex believes it becomes profitable when about 4% of annual energy production from a given wind farm would be lost due to ice. Lehtomäki argues that anti-icing technology should be considered with production losses of 2-3%, stressing that there is more to the cost-benefit equation than just the price.
For instance, banks feel more comfortable about lending when such equipment is used. “Even if cold-climate technology is expensive, half of the additional cost is covered by lower interest rates granted by banks,” he says.
Obviously, other factors also have to be taken into account, such as site accessibility — ice, snow, altitude and the remoteness of a project can increase the cost of O&M.
“In most cases we can demonstrate that if a customer is buying, for example, a de-icing system, the enhanced energy production is compensating for the investment,” says Senvion portfolio manager Stefan Philipp.
“A second motivation is safety, which you can barely measure in money.”
Ice on spinning rotor blades can be thrown several hundred metres, potentially injuring or killing technicians or passers-by, as well as damaging property.
Koljonen notes that there are no formalised standards for predicting icing events, which further complicates matters, although he adds that guidance is being developed by various bodies, including the International Energy Agency.
Robert Hornung, president of the Canadian Wind Energy Association, points out that site accessibility can also affect health and safety considerations — especially with regard to emergency evacuations and the risks of workers being left stranded amid freezing conditions.
In some cold regions, there is a growing market to retrofit de-icing systems to existing turbines.
Wicetec, a VTT spin-off company, is working with an O&M firm in Canada to add electrical heating systems and other ice-prevention features to hundreds of megawatts of already installed machines.
In China, many major turbine makers now offer cold-climate solutions. OEMs such as United Power already provide de-icing technology, while compatriot Dongfang is due to add nine cold-climate turbines to the 30 it has installed at the 250MW Blaiken project in northern Sweden. Envision is also trying to sell cold-climate machines into Sweden.
Conversely, Western manufacturers with a firm foothold in China — Gamesa, Vestas and GE — have an opportunity in its cold-climate regions, due to their ability to tailor turbines for specific projects, especially in challenging environmental conditions.
Competition among OEMs is growing, and more opportunities are opening up. It seems clear that in the coming years, cold-climate wind power will become an increasingly hot market.
Additional reporting by Brian Publicover and Karl-Erik Stromsta