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The production of electricity from renewable sources is highly unstable, especially as wind and solar energy, and hydro power strongly depend on weather and climate conditions. The things that make today’s power system so unusually unique are its unwavering demand and the irregularities in the inputs to the general power grid. As these two things obviously go hand in hand, some adjustments are required, as well as more efficient storage systems. Here is where Buoyant Energy comes in.

Within the European Union the percentage of renewable energy sources in relation to the annual gross energy consumption was at 8.5% in 2008. As of 2009 every EU member state had a new goal: to have a pre-agreed amount of energy consumption come from renewable energy sources, so that the EU as a whole will come to a total of 20% by the year 2020, also known as the 20-20-20 Directive (Directive 2009/28/EC1 ) . Germany’s percent of energy generation from renewable energy sources has increased from 3.1% in 1990 to 17.1% in 2010 (BMU, 20112). The main renewable energy sources in 2010 were wind (6.2% of total electric production), hydropower (3.4%), biogas (2.4%) and solar power (1.9%) (BMU, 20112).

While the planned construction of large offshore wind energy capacitances in the European North and Baltic Seas, as well as the repowering of existing onshore wind turbines, may increase the power generation capacitances in the north-eastern provinces of Germany, there is still the issue of what to do with the newly produced energy, that can’t be stored. The aforementioned provinces of Germany lack the topographical qualities necessary for the construction of conventional pumped storage plants. All of the extra power transmission necessary for the adequate storage of the additional energy would put extensive pressure on the existing power grid. According to the dena Grid Study I, (20053) about 14 GW of additional storage capacity will be needed in Germany by 2020.

1 European Commission (2009): Directive 2009/28/EG

2 BMU – Federal Ministry for the Environment, Nature Conservation and Nuclear Safety.
Renewable Energy Sources in Figures

3 German Energy Agency, Integration of Onshore and Offshore Wind Energy, Generated within Germany, into the National Grid by the Year 2020. dena – Grid Study