The challenges of climate change involve totally rethinking the world’s energy system. In particular, CCS technologies are still presented as a solution to reach ambitious climate targets. However, avoiding the required Gt of CO2 emissions by investing in CCS technologies supposes the development of carbon storage capacities. This analysis, conducted with TIAM-FR and based on a wide review of geological storage potential and various data, aims to discuss the impact of this potential on the development of the CCS option. We also specify a scenario allowing the exclusion of onshore storage due to a hypothetic policy considering public resistance to onshore storage, and carbon transport costs variation effects. The implementation of CCS is less impacted by the level of carbon storage potential - except in the lowest case of availability - than by the type of sequestration site. However, the development of CCS is lower at the end of the period in the case of a decrease in carbon storage potential. Indeed, the question of type of storage site appears to have a greater impact, with an arbitrage between deep saline aquifers and depleted basins and enhanced recovery. Doubling the cost of carbon transport does not limit the penetration of carbon capture technologies, but it does impact the choice of site. Finally, a limitation of onshore storage could have a significant impact on the penetration of the CCS option. The explanation for this limited deployment of CCS is thus the higher cost of offshore storage more than the level of storage potential.