The development of high performance solar cells suitable for cost effective and low CTM (cell-to-module)-loss module fabrication is a major goal of current R&D activities.Our approach to achieve this goal combines the HIP-MWT (high performance metal wrap through) cell concept and the cost efficient ribbon based interconnection process.In comparison to other back-contact module approaches (e.g.conductive back sheet foil) the conventional module fabrication process needs only little adaptions of the stringing process,which leads to exceptionally low investment costs.This allows a fast and simple conversion of current production lines towards higher module efficiencies.Cell efficiencies over 20% (Cz-Si,p-type,156 x 156 mm2) demonstrate the high potential of the HIP-MWT cell concept and are achieved by using production technologies close to the industrial standard (e.g.thermal oxidation,single-side wet chemical polishing and etching,local rear side contacting,screen-printing).Successful pilot-line processing of several thousand solar cells approve for the applicability of the HIP-MWT concept for mass production.Moreover,the HIP-MWF cell design was selected to reduce overall costs and increase the resulting module efficiencies for a ribbon based interconnection,which allows for CTM power losses of less than 1%.A 60 cell back contact demonstrator MVVT module with a new,innovative cell interconnection design will be exhibited at SNEC and the CTM losses will be reported in detail.We will present significant cost savings (in (∈)/Wp) in comparison to conventional modules (solar cells with Al-BSF and 3 bus bars) and to the conductive backsheet foil approach for back contact modules.