Understanding Onshore Wind Farm Construction in Cold Climates | A site visit to Åskälen and Munkflohögen with Vasa Vind
So, this spring has definitely been one for history to remember, and all of a sudden, we are in June (how on earth did that happen)? Anyway, they say better late than never and I'm going to apply this saying here, as even though summer is about to arrive, there will once again come a time when snow covers the northern hemisphere of Europe, and hence, this article may be of interest for the future. Also, my colleague Kajsa Karlsson wrote another article about our site visit, talking about service and maintenance in cold climates which you can find below:
I , however, will speak more about the challenges relating to the construction side of things when dealing with cold climates (and tonnes of snow)!
The annual Winterwind trade show takes place every year in February, this time in Åre, close to the Norwegian border. The trade show is focused on wind energy in cold climates and attracts scientists, engineers, manufacturers, developers, consultants, investors, wind farm owners, and O&M providers, as well as representatives from government agencies from all over the world, who gather in northern Sweden to discuss the challenges of generating wind power in cold climates (winterwind.se).
During the first day of the gathering, a field trip was organised by Vasa Vind to their two wind farms north of Östersund, Åskälen, and Munkflohögen. This is a rare and exciting opportunity for me to visit a wind farm and gain a deeper understanding of the challenges involved in constructing large-scale wind farms in a cold climate.
We started out the day with a visit to the chocolate factory in Åre (because everyone knows that to endure a bus journey, you need snacks). This is a lovely little local business, with delicious chocolate.
I would actually highly recommend a visit if you find yourself in Åre, but if not, you can actually find their products in smaller shops in Sweden as well. It has been around for almost 30 years (founded in 1991). If interested, you can check out some more about it on www.arechokladfabrik.se
Once we were all ready, we hopped on the bus out to Åskälen and Munkflohögen wind farms, which are situated approximately 50 km north of Östersund in Jämtland County. The sites were selected due to good average wind speeds and proximity to necessary infrastructure with existing forest tracks that were utilised and developed during construction, as well as a nearby grid connection. The area is mainly compromised of privately-owned forestland, and the sites were acquired by Vasa Vind back in 2013. The Munkflohögen site consists of 23 Vestas V110 turbines with a production capacity of 49MW, and Åskälen has 80 Vestas V136 turbines with a capacity of 288MW, giving the area a combined production capacity of 337MW annually. As it stands, this is one of Swedens larger wind farms now in operation, although with several sizeable new sites under construction, that is due to change very soon.
After a journey into the beautiful winter landscape (on which we partook in a fun quiz I might add), we arrived at the site office for lunch. Here we were greeted by the Vasa Vind team and served with a lovely lunch in their site office. I must say I was impressed with the quality of the site office and we were told that the wood for the site office actually came from the trees that had been cut down during the construction phase. This was done as to not waste any materials but use what they could locally. In the renewable energy spirit, it is grand.
After lunch, we were invited to listen to a presentation from the Vasa Vind tram about the sites and the process of building the farms. Here the team spoke about some of the challenges they encountered during the construction phase. During the construction of Munkflohögen, they had the coldest 2 winters recorded in the area for ages, with temperatures dropping to -33 degrees Celcius. Now, I don't know about you but I would say that's a pretty cold climate to conduct any outdoor work, however, the team did well.
So, since civil works essentially need summer conditions to take place, the work with roads was mainly undertaken during the summer periods, focusing on transportation during the winter months.
As the snow tends to melt during April to June there is some risk in transporting large equipment then, and therefore it is actually less of a risk to transport during the winter as the snow provides a form of isolation on the ground, avoiding ice, making it more stable for transport.
One thing which should be praised in these projects is that Vasa Vind tried to use mainly local companies wherever possible for the construction and operations phase of the sites (Vindkraftscentrum, 2019). During the construction phase of Munkflohögen and Åskälen, 84% of the work has been conducted by local or regional companies, and the number of jobs has surmounted to approximately 140, directly benefitting the local economy in the area. Of the 226 companies involved in the project, 177 of them have been local to the region (Vindkraftscentrum, 2019).
This has not only helped with acceptance toward wind power in the region but also provided an opportunity for economic growth. With a life span of 25 years the wind farms will continue to offer local job opportunities even now when they move into the operational phase.
Through the presentation, Vasa Vind also spoke about the HSE considerations, and how these change during construction in winter conditions. During the construction phase, there had been 178 HSE observations to learn from, such as iced up pipes for the water supply to the office to name one. Overall the projects have been conducted in a very HSE oriented manner, and I believe the thing to take from this is precisely what Vasa Vind pointed out; there are new considerations to take into account when you are working in winter conditions. Another aspect they encountered in the installation phase is the icing on cranes, which can damage both the equipment itself but also cause accidents.
Roads, crane plans, foundation work, internal cable networks, and airborne electrical lines for distribution from the wind farm Åskälen was carried out by Stenger & Ibsen Construction. As an honourable mention, I would like to point out how impressive it is that the construction team managed to pour 100 foundations in 7 months! This is without a doubt an impressive record. The foundations are 3,5 m in depth, anchor cage standing on binding.
Once the presentation was concluded, we were provided with helmets and reflective vests, to then hop on the bus and head out to check out the turbines. On the way out we encountered stunning views from the bus (as you can see pictured above). Whoever says wind turbines ruin the landscape more than heavy plants and industry, I just cannot see where they are coming from. In my opinion, the turbines look majestic, towering over the winter landscape of beautiful Jämtland. We really managed to get brilliant weather for our trip as well, so that is a bonus.
We got to take some photos and then headed on to check out the inside of a turbine tower. For me, very exciting as I had never been in one previously. It is quite impressive when you're standing outside next to the turbine as well, as the sheer height of them becomes more obvious. It also becomes evident when you are inside the turbine why wind turbine techs need to undertake health tests to check their heart rate and general fitness as if the lift is broken, the ladder needs to be climbed. And its quite far to get to the turbine itself!
I could not resist having my photo taken with the wind turbines, in full gear (so I used this picture as my author image in this article). Sometimes I feel sad I am not as technically savvy as some, as I think I may have enjoyed working outside. However, not in -33 degrees Celcius if I am to be completely honest!
At this stop, we also got some further info in the operations of the turbines from Vasa Vind, and took a group photo which I am sure I have seen somewhere after the trade show, but cannot seem to find now.
As the sun started setting, it was time to get back on the bus and return back to Åre. I am happy to say that I learned a lot during the visit. Now all I have left is to actually get myself up a turbine as well, although I know this comes with its own safety procedures and permits.
I would like to thank Vasa Vind for hosting us, we had a great time! I for one will definitely come back to Jämtland as well, as I fell in love with the wintry mountains and fresh air. Since it is somewhat of a hub for wind energy, I am sure that I will have plenty of reasons to return.
If you want to know more about the projects, or Vasa Vind, visit www.vasavind.se
I hope you enjoyed the summary of the visit to Munkflohögen and Åskälen, and feel free to share in your own networks.
Senior Recruitment Consultant
Cathcart Associated Energy Ltd.