Initially when the snap shots of the diesel engined Chevrolet Beat began doing the rounds the badge was clearly XSDE which was supposed to be Xtra Smart Diesel Engine and this was supposed to be consistent with the nomenclature of Smartech that the petrol engine uses.  But now there is a clear picture posted on Indian Cars which shows the diesel Beat carrying the TCDi badge which stands for Turbo Common Raid Diesel injection.  TCDi is the preferred nomenclature of an engine that runs on a fixed geometry turbo charger.  VCDi is used in case the turbo charger uses a variable geometry.