Electricity is green: a self-fulfilling prophecy? We want to see this become reality in 2050. 
The claim "Strom ist grün." (Electricity is green) is a bold statement, but only with a clear goal in mind we can achieve what is best for all of us. 
The green bolt and the 100% represent the power of the idea and explain briefly what it is all about: 100% green energy. The additional information can be arranged in different combinations, thus opening enough possibilities for a variety of communincation levels.