2020 autumn storm inspection PoC for Järvi-Suomen Energia in Finland
Background
Hepta conducted a quick power line storm inspection with drones in September 2020 after strong autumn storm Aila. The works were conducted in Mikkeli, Finland for Järvi-Suomen Energia (JSE) and in Lahti area for Kymenlaakson Sähkö (KS).
Järvi-Suomen Energia (JSE) builds, maintains, and develops the electricity network of Finland’s unique lake district. As the local distribution system operator, JSE maintains an electricity grid of approximately 27 000 kilometers. Kymenlaakson Sähkö (KS) is an energy group owned by 10 towns and municipalities.
Hepta was invited by JSE to conduct an operative powerline inspection after autumn storm Aila in Mikkeli, Finland. The goal was to find the causes of blackouts affecting up to 1000 homes. The storm inspection with the drone was conducted in conjunction with the ground maintenance crew to fix the issues as soon as possible.
The weather was not very pleasant, with light rain and wind gusting up to 12-18 m/s in the region. In total Hepta team flew 5 km of lines. On 3 separate lines, we discovered 1 possible tree which may have caused the blackout. 2 small birch trees lying on the ground, and another line that had 1 tree on conductors.
The landscape has many lakes and inhabited areas which are time-consuming to cover on foot.
Day One of Power Line Storm Inspection
This was the first time to provide storm inspection as a service proof of concept (PoC) to JSE while KS has been Hepta’s customer for 1.5 years. In addition to the usual equipment, Hepta team member Ryan Saar was operating drone DJI Matrice M210. Ryan commented:
“For me, it is routine to use new, slightly upgraded versions of drones and I prefer to know the equipment so I could use it with my eyes closed. On the first day, just before the storm peak, we gathered with the client’s team in the morning at 10:00 to discuss what input and how I will give with the drones. Also, what are the capabilities for drones in storm inspection, and what are the next actions in the future. We were still waiting for the storm winds to fall the trees to start the line inspection. At 11:00 we gathered for weather prognosis for upcoming hours and the wind was strong. At 13:00 (1 pm) we headed to the object to start the work.
During the day we had a dilemma to choose between two options – to use M210 or Mavic 2 drone. The M210 is more storm- and weatherproof and has a powerful camera. Mavic 2 is ten times cheaper but it is not meant to be flown in rain and storm.
The first pick was Mavic 2 and it performed fine in the winds around 12m/s. We found a couple of trees which had fallen through the line but were not suspended on the line.