| Ossberger GmbH Hydro powers ski resort
Above: Automation with touch screen in the turbine house
Left: Grau Roig ski resort
THE GRANDVALIRA SKI RESORT in Andorra has been operating a new small hydropower plant since December 2022, which utilises the energy of a mountain stream. The power plant in the Grau Roig sector of the resort was realised in around six months on the Pessons river. It can generate 1 million kWh of green electricity per year and thus contributes to the resort’s partial energy self-sufficiency. Hydropower plays an important role in Andorra, as around a quarter of the country’s electricity comes from this source. In addition, around 15% comes from other renewable sources such as wind and solar. Joan Viladomat, owner of the Pas de la Casa and Grau Roig ski sectors, looked at ways to improve the resort’s energy independence. A study in 2020 investigated the hydropower potential in the Grau Roig sector and planning permission was granted in autumn 2021. Construction began in June 2022. The operating principle of the power plant is based on the classic diversion concept, in which water is extracted from the stream bed and channelled to the power plant through a penstock. The water intake was newly constructed, as was the machine building. To ensure ecological continuity, a fish pass was
installed as well as a pipe system that ensures the ecological water flow of the river and is monitored on a 24/7 basis. The installed crossflow turbine was supplied by Ossberger, a German hydropower expert. Its operating range is between 2.5m and 200m head. The deliberately simple design of the machine with only three moving parts provides a reliable supply of electricity and copes extremely well with fluctuating water flows. This is made possible by the structure inside the turbine, which consists of two cells that operate independently of each other. As a result, the smaller cell only needs 5% of the volume of water to operate the turbine. For the Grau Roig power plant, Ossberger supplied a machine designed for 450 litres of water per second and a gross head of 96m. At full water supply, which is mainly available during the snowmelt in spring, the turbine generates 316kW of bottleneck power. The integrated bypass with plunger valve ensures that the water from the penstock can be redirected past the turbine during maintenance works. After a six-month construction phase, the power plant was put into operation for the first time in December 2022. However, electricity production only lasted a few days as the water volume fell sharply in winter. Three months later,
the power plant was able to resume operation. The deputy technical manager of the ski resort, Ferran Huertas Martínez, confirms that the Ossberger crossflow turbine delivers very good results with the fluctuating inflows that prevail at the site. The ski resort can now cover around 10% of its own energy requirements thanks to the hydroelectric power plant and several solar panels. The ski resort plans to further expand the use of renewable energies in order to achieve its goal of complete energy independence in two steps: firstly by achieving an annual net energy balance and secondly by adjusting production to consumption (currently more energy is produced in non-skiing periods, even though the main consumption is in the winter months). Ossberger, the German company that supplied the machine set for the crossflow turbine, has been an integral part of the small hydropower market since 1906. Over 10,000 machines have been installed worldwide and have been operating reliably for several decades. The company founder Fritz Ossberger developed the turbine, which is still in use today, himself and was granted several patents for it. This has resulted in the company’s high level of manufacturing expertise.
Above: Turbine set with crossflow turbine, bypass and direct-coupled generator
Right: Water intake in front of the hydropower plant
OSSBERGER GmbH + Co. KG, Otto-Rieder-Str. 5-11, 91781 Weissenburg / Germany +49 9141 977-0 |
info@ossberger.de |
www.ossberger.de
www.waterpowermagazine.com | May 2024 | 23
Advertisement feature
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77
