We are investigating the new TF-PV material called CZTS, based on abundant elements (Cu, Zn, Sn, S, Se) and using a proprietary low-cost fabrication method based on spraying of colloidal inks. Our present solar-to-electricity conversion efficiency is on a par with best laboratories in the world working on CZTS. We are actively contributing to the European Project Starcell ( www.starcell.eu). Our most important contributions have been the particular fabrication method, the tuning of some properties of the active CZTS layer, and the scale up of the complete photovoltaic device.