They’re not the kind of headlines we always get: “80% say yes to new power line”,
“Double, positive engagement between Terna and residents”; “Haunted by blackout,
new cable gets approval”. One mayor is quoted by the local press as saying: “The
territory’s needs have been heard.” Another adds: “This is great news and thanks
go to Terna for its choice.”.
All this is new in a country where energy infrastructure is commonly opposed by a
NIMBY (Not In My Back Yard) mentality and where hostile local groups can hold up
proposals for years. To adapt the Italian word for “yes”, we could even call this
a “SÌMBY” phenomenon (Sì In My Back Yard).
What’s more, it’s happening in Cortina d’Ampezzo, the Queen of the Dolomites that
sits like a jewel at the heart of breath-taking mountain scenery that in 2009 was
recognised by UNESCO as a World Heritage Site. The UN organisation describes it
as “some of the most beautiful mountain landscapes anywhere”.
But people in the Alto Bellunese valley remember clearly what happened at Christmas
2013. A 50-centimetre overnight dump of “wet” snow severed the only power line connecting
them to the national grid. Almost 60,000 users were left without power for the best part
of the day, mobile phones didn’t work and tourists were urged to stay in their hotels with
an avalanche cutting off road access. For some families, the power disruption lasted longer
- three or four days in some cases as lines were gradually restored.
Why does climate change pose a risk to power lines in the Alps?
On Boxing Day 2013
, the Dolomites were struck by a severe snowstorm with over half a metre of snow falling overnight.
Nothing new for the Alps, of course. But climate change
has led to higher winter temperatures and more intense bouts of precipitation, meaning
snowfall can be heavy and “wet”. A thick layer of snow built up around power lines and then froze to form a sort of icy sleeve around the cables,
causing them to break under the weight. (Freezing rain can have the same effect). Trees that were overburdened with snow fell onto the cables too.
The Terna network as well as medium- and low-voltage lines were affected.
The resulting outage paralysed Cortina and the rest of the valley in the middle of the Christmas holiday season. A similar snowfall a month later, which cut
off power to 30,000 users in neighbouring valleys, was a reminder that the Cortina event was not a one-off but a long-term shift in weather patterns
poses a challenge to us and other network operators with infrastructure in mountainous or remote areas.
Read more about our impact on climate change
Involving the community in solving the problem
To resolve the problem, we needed to add a second power line to serve Cortina and avoid it being cut off again.
The resort can’t afford a similar episode as it prepares to host the World Ski Championships in 2021 and we couldn’t risk having our solution held up by local opposition.
That’s why we opted to involve the local community in finding a solution, guided by our inclusive
approach to stakeholder dialogue.
Rather than come to the valley’s population with a detailed proposal that might be met with hostility, we decided it was
best to share the problem with them and discuss how to find a mutually satisfactory solution.
Timeline: approval of a new power line
telephone survey of residents on expectations and engagement preferences
1st open meeting to present network development plans
2nd open meeting to define possible routes for the new power line
Next steps: approval of construction site with new cable to be in service by 2021..
dialogue with local authorities and Dolomites regional park to assess possible solutions
3rd open meeting to propose underground cable, agree route and feasibility
Terna submitted the application for authorization to the MISE
for the “Reorganization of the National Transmission Grid in the area of Alto Bellunese”
What does the local community think?
of residents remember the extraordinary snowfalls of 2013-14
worry it might happen again
realise security of supply depends on number of power lines
approve idea to build a second power line (Cortina-Auronzo)
keen to take part in decision (e.g. open days, conferences…)
The solution: bury the new cable underground
The local community was clear in its opposition to an overhead power line. As an alternative,
we came up with a plan to build a 132-kilovolt (kV) power line underground along a 24 kilometre route.
The cable would go between Cortina and the new substation at Auronzo di Cadore, in
turn connected to the 220 kV national network. That way, in an emergency, the Cortina area would have a back-up link to the grid.
Apart from the beauty of the area, our engineers and the local community needed to take into consideration
a multitude of factors in getting the right solution (as we always do to mitigate the impact of our infrastructure):
how to pass mostly under publicly owned land or roads rather than private property; the problem of going through muddy
terrain and the associated risk of landslides; staying away from ski lifts. The idea of using woodland tracks and
country roads came from the Park Authority of the Ampezzo Dolomites.
We’re very satisfied because the project as it was presented [at the end]
was the product of close collaboration between Terna and local authorities.
It was a big effort in which we had a leading role with the aim of choosing the
solution with the least impact – in other words an underground cable – and that
would disturb homes the least and would be economically and materially feasible.
This approach to dialogue has become the “Cortina model”: we started with a blank
sheet of paper and together we plotted the route to take.
Gianpietro Ghedina - Sindaco di Cortina d'Ampezzo
Pros and cons of burying cables underground compared with overhead lines
✓ Eliminates visual impact
✓ Liked by local communities
✗ Bigger impact during construction, e.g. on road traffic
✗ Repairs take longer, compromising continuity of service
✗ Higher construction costs (5 to 10 times cost of overhead line)