Wind turbine safety must be improved
The Safety Investigation Authority has examined the information received concerning the wind turbine fire in Hamina that started on the night of 6 January 2017. The fire started in the machine room of a wind turbine, at a high elevation, and was practically impossible to extinguish using the methods available to the rescue services. There were no fixed fire suppression systems.
In cases of wind turbine malfunctions such as fires, a significant risk as noted in several incidents in Finland and abroad is the separation of the large turbine blades, which may be propelled hundreds of metres away from the turbine. This constitutes a hazard to nearby housing, industry, road traffic and rescue operations. Flying debris makes fire-fighting, evacuation and the suppression of any fires on the ground difficult.
In 2014, a wind turbine on Reposaari in Pori overspan. Shards from the blades were flung onto a highway, which however had already been sealed off. Wind turbine fires have been recorded at least in Uusikaupunki in 2004 and in Estonia in 2015. According to press reports of the Estonian incident, burning debris fell at distances up to 400 m from the wind turbine, igniting fires on the ground.
Fire suppression systems and defined safety distances required for wind turbines
In Hamina, there are industrial facilities and storage tanks for flammable liquids less than 300 m from the wind turbine that caught fire. In this particular incident, the responders managed to stop the wind turbine, albeit with some difficulty. Thanks to this, the blades did not fall to the ground until later, when the fire had already been put out.
The Safety Investigation Authority will not be launching an investigation into this fire but does express concern about the safety of wind turbines.
The Ministry of the Environment and other relevant operators should jointly agree on principles whereby sufficient safety may be ensured for existing and future wind turbines. Fire suppression systems and defined safety distances are essential. These concerns were also voiced by the rescue services partnership network in a letter and recommendation back in 2014.
At the moment, guidelines on the construction of wind turbines are given in the publication Ympäristöhallinnon ohjeita 5/2016. Tuulivoimarakentamisen suunnittelu [Environmental Administration Guidelines 5/2016. Planning wind farm construction].
Veli-Pekka Nurmi, Executive Director of the Safety Investigation Authority, tel. 0295 150 701 (Twitter: @VPNurmi)
Kai Valonen, Chief Safety Investigator at the Safety Investigation Authority, tel. 0295 150 707 (Twitter: @KValonen)