10 years ago, Christoph Ostermann and Thorsten Stiefenhofer reinvented energy transition: they founded the company sonnen in Allgäu. Over the next 10 years, this manufacturer of battery storage systems became the world market leader for power storage systems. With over 50,000 systems installed, its own electricity...

The importance of legally watertight guarantee clauses for innovative products in the renewable energy sector was demonstrated to great effect in the autumn of 2018: The Verbraucherzentrale NRW e.V. (NRW Consumer Organisation) requested that five German battery storage manufacturers refrained from using various warranty clauses....