Is Germany on its way to genuine energy independence and 100% reliance on renewable energy sources? An experiment conducted by the University of Kassel in cooperation with three energy companies challenges the conventional wisdom on renewable energy and suggests that nuclear and fossil fuel energy can be fazed out and replaced with renewables - without disrupting the supply of electricity to the national grid. Renewable energy has its limits. On cloudy days, the sun doesn't reach solar panels, and sometimes there is no wind to power windmills. Germany's scientists, however, have put together an experimental "Combined Power Plant" which draws its energy from 36 different solar, wind, biogas and hydroelectric power plants located in different parts of the country. The goal is to prove that renewable energy can provide a consistent and reliable supply of energy, in all weather conditions and in the face of fluctuating demand.
And, for now, they have proven that it is possible, at least on a small scale. The experiment provides enough energy to meet 100% of the annual needs of a small town with 12,000 households. Says Professor Jürgen Schmid of the University of Kassel:
If renewables continue to grow as they have done in the past, they’ll provide around 40% of Germany’s electricity needs by 2020. We could therefore achieve 100% by the middle of the century.
One interesting innovation is a mechanism for storing wind energy during times when more electricity is being produced than is demanded by the grid. Excess energy is used to pump water up a hill, where it is stored in a large reservoir. The stored water is then released during peak electricity consumption hours, flowing downhill to create additional energy. "Storing" energy in this way improves the consistency of supply of electricity, regardless of the weather.