Energy storage in urban areas!
One of the most important energy-political issues dealt with in the field of renewable energies in Germany and Europe is the development / expansion of energy storage stations in order to buffer or store the so-called “green electricity”. Power generation from wind and sunlight is developing intensively in Germany and worldwide. Looking at the fact that electricity generation from the power of wind and sunlight is subject to high fluctuations in time and weather conditions, electric energy is generated independently of the demand and therefore additional storage capacities are necessary.
Pumped storage power plants are seen as a generally good fit for intermediate storage purposes. If by way of example electricity is generated in windy weather conditions on weekends and no customer is found, the electricity is sold at the stock market (to some extent for 0 or even a negative price) in order to run pumped storage power plants for instance in Austria. With this surplus of electricity water is pumped up a mountain into a large water reservoir (in other words converted into potential energy). If energy is needed at times of high or peak loads, the pumped storage power plant is connected to the power network and converts the potential energy of the water back into electricity by flowing down the mountain and through turbines. The water flows into a lower reservoir and is ready for the circulation in the pumped storage power plant.
This principle is very interesting for operating companies as high prices can be attained in times of peak loads. The urban energy storage power plant with large expansion and low height potentiality can work same way. 
An artificially created harbour basin (often with historical origins) with direct access to the river lying idle and is economically unused and available in urban areas. The harbour basin of the “Wissenschaftshafen” in Magdeburg could be converted to a test plant of energy storage. For this purpose the harbour basin will be separated from the Elbe with a wall/sluice. In this wall a pump-turbine is integrated. This version allows two different scenarios for the use of the storage basin. In one scenario the difference of water levels between Elbe and empty storage basin is used. Another scenario is to fill the storage basin till a certain water depth and then use the difference between storage basin and Elbe. Both scenarios show that a high potential exists to use this storage basin as latent energy storage with large expansion and low height potentiality economically in an urban area. In the appendix you will find a description of the scenarios through the example of the “Wissenschaftshafen” Magdeburg.
Such storage is perfect to balance out main power fluctuations (imbalance between requirement and generation of electricity) and also have an effect on stability of electricity network. These technical characteristics allow the use for the balancing energy market and for own use. Consequently these constructions are suitable for the maintenance of the network stability as well as for smoothing the load and injection.
The energy storage power plant offers a high system quality caused by a high flexibility and high security.

The previously installed Power in form of pumped storage power plants in Germany is not enough because the demand constantly increases. For this reason an energy storage power plant in urban areas is a next step for solution of the problem. The previous pumped storage power plants are located far from housing complexes and have to be built extensively. Harbour basins among urban areas could be used as energy storage power plants. They are ecologically compatible and can form the landscape. It’s a possibility to store electricity with high efficiency on a large scale and to spend it local if required. The interesting side effects of “urban energy storage power plants” in addition to economic effects which caused by unused areas at many places, can be a considerably appreciation and improvement of the aesthetics because water and energy will be experienced. The prototype for the first urban energy storage power plant shall be built and developed directly located at the “Wissenschaftshafen” Magdeburg.