A comparison between thin film and c-Si PV technologies for MW size applications

In the last few years the thin film PV technology market share has steadily grown thanks to its lower manufacturing cost in comparison with traditional crystalline silicon technologies. While thin film PV modules have shown their potential in special applications where c-Si modules are unsuitable, like building integration, the use of these modules in large scale PV power plants requires a detailed economic analysis to assess if these technologies can be cost-competitive in a time when c-Si is showing a great potential on cost reduction. In this paper three technologies are compared in a technological and economic point of view. The main technological advantages and weaknesses of multi-crystalline silicon, amorphous micro-crystalline silicon and cadmium telluride PV modules are analyzed and an economical analysis is made for assessing the economic viability of each technology for a 1 MW power plant installed in Southern Italy. The comparison is made evaluating the cost of the energy produced by the three technologies in the same environmental condition during a 20 years lifetime. The model evaluates the total energy yield of the different technologies considering the actual performance in field conditions. This allows to consider the better behavior of thin film PV modules with low and diffuse radiation, together with the different behavior with temperature. All the main cost drivers, such as manufacturing, installation, operation and maintenance costs, as well as tracking system, balance of system and land use costs are used for assessing which technology best suites for a MW size PV power plant application and how big is the gap between the leading technology and the emerging ones.