We investigate the potential advantages of using very high resistivity n- and p-type, to manufacture high performance solar cells. Analytical modeling indicates that high resistivity substrates (10 Ωcm - >1k Ωcm) are required to have bulk Shockley-Read-Hall lifetimes in the millisecond range to outperform wafers with standard resistivities (< 10 Ωcm). Additionally, for resistivities over 10 Ω.cm, efficiencies show to be weakly dependent of the bulk resistivity. These results if experimental verified, can lead to more affordable ingot manufacturing, by lessening the requirements of dopants homogeneity along the ingot. We successfully passivated both n- and p- type substrates using i-a-Si:H, obtaining surface saturation current densities below 10 fAcm-2 and effective minority-carrier lifetimes over 2 ms at maximum power over the entire range of bulk resistivities (3 Ωcm- >10k Ωcm).