Fresh breeze and warm sun for pumped storage

In recent years, the need for new or additional pumped-storage schemes has been recognized worldwide, as these schemes provide the most economical method for conserving large quantities of energy at a reasonable efficiency level. In addition, pumped-storage hydro is the only renewable energy source that can deliver positive or negative reserve to the grid for balancing intermittent resources such as wind and solar. The increasing contribution of these resources has led to an increase demand for pumped storage, especially in southern and western parts of Europe. Therefore, pumped storage plays a vital role in building low emission capacity for generating electricity, and in meeting targets for reduced greenhouse gas emissions. Much of the pumped-storage capacity operating worldwide was built 30 to 50 years ago. Consequently, at many plants refurbishment and modernization of equipment are attractive options to increase efficiency and capacity. New pumped-storage stations benefit from the technological achievements in the areas of hydraulic and electrical machines as well as the automation sector.