Measuring the Wind in Extreme Northern Latitudes
If you’ve never been very far north or south of the equator, it can be hard to imagine what the long, cold, dark winter is like. Residents say they like snowfall because it brightens up the long winter nights.
If you fly north for one hour from Helsinki, you come to Oulu — northern Finland’s largest city. Drive for another hour and you will come to one of the forested parcels where Puhuri, a consortium of utilities that develops renewable energy in the Nordics, operates a wind park. This is the site we visited in June with Teppo Hilakivi and Timo Annola, two of Puhuri’s technicians.
Met towers are costly to use in measuring wind. "It might take 2 months to get all the permits for building a working measurement mast," explained Teppo. Failure can be catastrophic. "We use heated measurement devices, but even they can freeze in winter conditions," Teppo told us. The solution was to use Vaisala's Triton - a remote sensing system designed to measure wind at higher heights and endure challenging weather and climate conditions.
Remote sensing technology give the wind industry a whole new way to do wind resource assessment and monitor the wind on operating wind parks. Now, instead of building met towers, a wind park developer can bring in a Triton and deploy it in less than a day.
Like many wind energy companies, Puhuri uses their Tritons to supplement data from their met towers, not to completely replace them. They use the met tower to get data up to 80 or 100 meters, and the Triton provides measurements up to 200 meters.
"The main reasons why we chose Triton instead of another measurement system were ease of use, long up-time, and cost effectiveness. In addition we can easily relocate it to measure many different places around our wind parks," Teppo explained.
Thanks to the advances in remote sensing technology, data loss due to freezing weather or lack of fuel is off their list of worries. With the help of this advanced technology, Puhuri is building more wind parks all over northern Finland.
"Being part of the change from fossil fuel to renewables means a great deal for me. This is not the future any more - it’s already happening today," says Teppo.