Page 93

significantly to regulating and stabilizing the power grid. This special combination of storage system, reserve power and flexibility makes pumped storage plants true multi-functional power stations for ensuring system adequacy. The fact that pumped storage systems can be coupled with other sources of renewable energy is another great benefit. As already mentioned, electricity is not always generated and consumed at the same time. Fluctuations in the electricity grid occur at all times. So-called hybrid plants, for example a pumped storage system with wind or photovoltaic units, will generate reliable and affordable electricity in the future. One project for hybrid plants was initiated in Germany: a natural energy storage plant combining the pumped storage hydro-electric power station with a wind farm.The principle behind this hybrid plant with Francis turbines (total output of 16 megawatts) being used, is simple and ingenious: if there is a surplus of power, the pumped storage power station switches to pumping mode moving water from a lower reservoir to the higher storage basin in the wind towers. If the demand for electricity in the grid rises, more electricity is generated by the turbines within seconds and fed back into the electricity grid. In this way, hybrid projects signify a major step forward in the use of renewable energy, as they balance the fluctuations of power demand and supply and ensure system adequacy.CONCLUSIONHydropower is renewable, reliable, affordable and good for economic and social development. Its storage and base load capabilities as well as the low carbon dioxide emissions make hydropower a valuable resource in achieving current climate targets. Moreover, hydropower is versatile and offers great unexploited potential in highly industrialized countries as well as in emerging or developing regions such as Africa. The demand for pumped storage power plants will continue to grow worldwide as they pave the way to increased use of renewable energy sources. The great challenge will be the use of fluctuating renewable energies in the face of the world’s increasing demand for energy, as the use of the internet and data streaming rises and industrial production increases. ■ABOUT THE AUTHOR After studying industrial engineering at Esslingen Technical University, Germany, Uwe Wehnhardt held various positions at major international companies such as Procter & Gamble or Alfred Kärcher, where he had worked abroad for several years. He joined Voith in 2007 and has been a Member of the Management Board of Voith Hydro since 2011. Since 1 January 2016 Mr Wehnhardt has been a member of the Corporate Board of Management and Chairman of the Management BoPictured: Uwe Wehnhardtard of Voith Hydro.A better future through climate protection The storage capabilities and low carbon dioxide emissions make hydropower a valuable resource in achieving climate targets. The use of hydropower has a significant impact on global climate protection. It reduces annual global CO2 emissions by 3.5 billion tons every year. In the US, for example, 225 million tons of CO2 pollution is avoided each year thanks to hydropower. Current model calculations show that between 2015 and 2050 more than 120 billion tons of global CO2 emissions will be avoided by the use of hydropower. According to the 2015 Hydropower Report of the World Energy Council, countries in which the share of hydropower in the electricity production is higher than the average generally have lower CO2 emissions per kWh of electricity generated. For this reason an ever increasing number of countries around the world are turning to the potential of hydropower. Especially the demand for pumped storage power plants will continue to grow worldwide as they prepare the way for the increased use of renewable energy.Voith GmbH Global Market Communication St. Poeltener Str.43 89522 Heidenheim, GermanySUSTAINABLE ENERGY 093