turbine water to produce electricity when the demand is high and/or prices are high. PSP are often designed with a relative high capacity to operate in turbine or pumping mode only for some hours each. They often use artificial reservoirs with limited capacity of storing water.
Environmental impacts of hydropower and pumped storage plants are related to impacts of flooding land to create a reservoir, the barrier effect disturbing the connectivity in the river and impacts on the flow regime and related ecosystem downstream from the dam. The world-wide installed PSH capacity today adds up to around 130 GW. About 24 GW is
added since 2005, and projections indicates installation of as much as 500-600 GW more PSH until 2050. As of today, Norway has 1250 hydropower stations with in total 30.14 GW of installed capacity, a yearly production of 130 TWh and a storage potential of 84 TWh, which makes up 50 % of the total storage capacity in Europe. In future, the large storage potential existing in Norway could be used to balance fluctuations in power generation of intermittent renewable energy sources in the European power grid. The intention is to extend existing hydropower
stations for the use of pumped storage without constructing new dams or reservoirs. These pumped storage hydropower facilities could be used to back-up the electricity production in times with little generation from wind and solar power, and to absorb energy and pump back water when wind and solar power production is high. This presentation will mainly a case study on large-scale energy storage and balancing services from Norwegian hydropower to Europe, showing the technical potential to develop 20 000 MW of new hydro where about 10 000 MW includes pumping.