South Tyrolean hydro-tech double proves its worth in the fjord

Not far from the northern Norwegian port town of Narvik the South Tyrolean Troyer AG equipped two new small-scale power plants with electromechanical equipment and control technology. In a regular operating year the plants achieve a power output of around 19 Gigawatt hours.

photo credits: Troyer AG

SOUTH TYROLEAN HYDRO-TECHNOLOGY DOUBLE PROVES ITS WORTH IN THE NORWEGIAN FJORD

In northern Norway, not far from the well-known port city of Narvik, two new, high-performance small hydropower plants were put into operation in spring 2021. The expert operational managers at the Norwegian Russvikkraft AS relied on the technical know-how of the South Tyrolean hydropower all-rounder Troyer AG, which supplied the entire electromechanical equipment for the two plants. In an average year the two hydropower stations – a 2.85 MW Francis turbine, and a 4-nozzlePelton turbine producing around 5 MW – feed a total of 19 GWh of energy along the cable beneath the lake. For Troyer this was a successful entry in an exciting hydropower market in the far north.

Tysfjord in the province of Nordland boasts some of the most scenic landscapes in the whole of Norway. The eponymous fjord is the deepest in northern Norway, while the steep surrounding mountains reach far up into the sky. There are glaciers, limestone caves, and the largest natural canyon in Northern Europe. No wonder it’s considered a paradise for all brands of hikers, anglers and naturelovers – not to mention the inland possibilities for skiers not far from the port of Narvik. The online US outdoor pursuits magazine ‘Outside’ lists Narvikfjellet as one of the ten best undiscovered skiing regions in Europe. Narvik, the regional capital, is famous for several reasons. Thanks to the Gulf Stream, the climate here is relatively mild and the harbour is icefree all year round. For centuries it has been a hub for the transportation of the iron ore mined in Lapland. This strategic importance made the port a target during the Second World War. Numerous monuments and a special war museum in the town still bear witness to the 2month Battle of Narvik in the spring of 1940. Narvik is also famous around the world as a tourist magnet for guests seeking the midnight sun. On long summer days the sun never dips behind the horizon and bathes the surrounding scenery in dreamy tones of orange and red.

HYDROELECTRIC POWER IS A POPULAR EXPORT It is obvious that in such a natural landscape worthy of protection, energy supply is based on natural resources. Indeed, hydropower has been the prevailing source of energy in Norway for a long time. The country is blessed with immense volumes of water and extreme topography. In 2020 Norway boasted around 1,700 hydroelectric power plants, accounting for approximately 88% of the country’s electricity production. Hydroelectric power is also an export hit: Norway recently exported around 14 TWh of green electricity abroad. Two experienced power generation companies joined forces here to share expertise and increase the amount of hydroelectric power generated in the Tysfjord region around Narvik. Småkraft AS is referred as Europe’s ‘largest smallscale power supplier’ and runs around 110 smallscale hydropower stations across Norway. Småkraft AS was joined by Nordkraft AS, whose portfolio encompasses 15 hydropower plants, to build two power plants on the Russvikelva river. Russvikkraft AS, founded together with five landowners, is the official operator of the two plants, which have been in operation since spring 2021.

MACHINERY TRANSPORTED VIA FERRY The region housing the site is very remote and cannot be accessed by land. This meant that the delivery of machinery and building materials would pose a challenge. Thomas Fiechter

photo credits: Troyer AG Troyer AG also delivered the ball valve to Norway.

photo credits: Troyer AG

The 4-jet Pelton turbine in the upper power plant is set up to provide around 5 MW of power.

was employed in executive project management for Troyer during the project: “The use of hydroelectric power was not something new here, however. After all, the landowner had a small hydropower plant in operation on site for selfsupply.” In January 2020 the site owner contacted the renowned South Tyrol hydropower company with a request to provide all the electromechanical infrastructure required for both Russvikelva power stations. Scope of delivery included turbines, water conduit pipes, valves and shutoffs, generators, hydraulic aggregates, cooling systems, low and mediumvoltage systems, general electrification, machine transformers and energy supply and control system for the water catchment. A classic watertowire job for the hydropower allrounders from South Tyrol.

photo credits: Troyer AG “The origins of this double project go back to 2014, when Nordkraft AS began developing it”, explains Bernt Grimstvedt, Troyer’s representative in Norway. Grimstvedt goes on to point out how strict the environmental guidelines are for the construction of smallscale hydropower plants in Norway. “Hydroelectric power stations are evaluated according to a whole range of ecological parameters, which all play a key role in the decision of the authorities on whether to approve a project.”

WATER FROM THE LAKES All the necessary permits had been approved for construction of the two hydropower plants – Øvre Russvik and Nedre Russvik by summer 2019, the project was ready to start. Conceptually, both plants are highpressure systems. The upper station, Øvre Russvik, guarantees a natural head of around 400 metres. The lower stage, Nedre Russvik, uses a head of around 100 m. Thomas Fiechter expands: “Both of these plants are fed by lakes and both intake structures consist of a steel intake cone with large slightlyangled, almostvertical rakes. The water is drawn into the catchment shaft via an intake pipe. The catchment shaft is made completely from PE and contains the pipe rupture shutoff valve, residual water supply, subsistence transformer and the control panel.” The DN700 ductile cast iron penstock down to the powerhouse at the upper plant is around 2,230 metres long. The lower stage penstock is around 650 metres long and made of

Foto:Wien Energie

The high-power Francis turbine is designed to produce 2.86 MW, efficiently processing the works water a stage below.

Technical Data

Øvre Russvik

• Flow Rate: 1.444 m3/s • Net Head: 390.2 m • Turbine: 4-nozzle Pelton Turbine • Manufacturer: Troyer AG • Nominal Output: 4,996 kW • Penstock: Length: approx. 2.23 km • Material: cast iron Ø DN700 • Average annual production: approx. 12 GWh

• Flow Rate: 3.363 m3/s • Net Head: 95.06 m • Turbine: 4-nozzle Pelton Turbine • Manufacturer: Troyer AG • Nominal Output: 2,858 kW • Penstock: Length: approx. 0.65 km • Material: GRP Ø DN1100 • Average annual production: approx. 7 GWh

Nedre Russvik

All the automation and control technology for both power plants was produced and installed by Troyer.

photo credits: Troyer AG

DN1100 GRP pipe. The whole construction phase took around 18 months to complete, after which the plant began to produce electricity for the first time.

ON-THE-JOB OBSTACLES Thomas Fiechter recounts: “We delivered the first components in August 2020: The cabling for both plants, the control cabinets and supply transformers for the catchments. The remaining mechanical infrastructure was delivered starting in January 2021.” This was no ordinary order, even for such an experienced project manager. Every single machine component and item of equipment had to be delivered by ferry as there is no road access to the site. The various pandemic related rules and restrictions applied during this period affected the project in a number of ways, and posed challenges for everyone involved. “Our assembly staff was on site from midMarch last year, but first had to spend 10 days in quarantine, and then accommodation units were strictly separated. Obviously, the restrictions made life that bit harder, and the various delays they caused triggered extra expense” Fiechter explained. By the end of May, beginning of June 2021, Troyer´s commissioning specialists had successfully connected both plants to the grid.

POWER FED ALONG AN UNDERGROUND CABLE BENEATH THE LAKE Øvre Russvik runs a 4jet Pelton turbine designed to process a standard flow rate of 1.444 m3/s. A net head of 390.2 metres allows the machine to reach a nominal output of 4.996 MW. The lower stage Nedre Russvik hydroelectric setup is slightly different. A Francis turbine was installed with an intake capacity of 3.363 m3/s. The net head of 95.06 metres equates to a nominal power output of 2.858 MW. The technical engineers at Troyer set up both machines with absolute precision to deal with the hydrological conditions at each site. Each machine is extremely efficient, durable and lowmaintenance. These were the attributes that had ultimately won over the Norwegian hydropower plant operators as Bernt Grimstvedt explains. “The extremely attractive combination of quality and a good price was the dealmaker that ensured Troyer’s bid was successful.” In an average year Øvre Russvik feeds around 12 GWh onto the grid, while the lowerstage Nedre Russvik plant feeds around 7 GWh. All of the electricity generated is transported via a cable below the lake and into the local 22kV grid power supply.

photo credits: Nordkraft A WIN-WIN PROJECT The operational benefit of both plants is that they can be run throughout the lowwater winter period. The plants are expected to supply around 3.2 GWh of electricity from the beginning of October to the end of April; a fact that delights both the cooperation partners, Småkraft AS and Nordkraft AS, and the five local land owners. The cooperation model is not only intended to provide more green electricity in the region, but also to secure value creation in the region, as Terjo Vedeler, CEO of Småkraft AS, outlined in an official statement: “Our model is about building a bridge between the national need for more renewable energy and local value creation and competence building. The projects on the Russvikelva are a good example of how we can collectively develop more forwardlooking renewable energy use.” Both energy businesses see the twoplant project as another building block in a strategy of expansion that will now include even more smallscale hydropower plants in the Nordland region. For Troyer, having equipped both plants, it was certainly a positive signal. Realisation of the Øvre Russvik and Nedre Russvik power plants marks a successful start to activity on the exciting Norwegian hydropower market, and several new projects follow soon. The signs are definitely promising!

photo credits: Troyer AG

Nordkraft’s CEO Eirik Frantzen and Småkraft’s CEO Terje Vedeler joined forces on the project to build the small-scale Russvik hydropower plants in Tysfjord. One special feature, indeed one major challenge of this Norwegian project, was that there were no access roads to the project site. All construction parts, machines and power station components had to be delivered by ferry.