The Think Tank was the first phase of Green City Energy and was held on 18 and 19 December 2009 at the Stazione Leopolda in Pisa.

Scientists, politicians, decision-makers, and representatives of the most advanced in Europe met to discuss the strategic lines of development of green energy city in Europe. From here, were designed on the guidelines which will assist the Forum of 1, 2 and July 3, 2010