(EnergyAsia, December 15) — US-based GT Solar Incorporated co-founder and CEO, Kedar Gupta, will retire from the company on December 31, 2006. President Tom Zarrella will lead the company and report to the board of directors.   Dr Gupta co-founded the company with his long time business partner, Jon Talbott, in 1994 with $1,000 between…