Life-cycle performance and financial impacts of the P-type to N-type transition in utility-scale photovoltaic systems

As the photovoltaic industry approaches the efficiency ceiling of P-type PERC technology, transitioning to N-type Tunnel Oxide Passivated Contact architectures is crucial for reducing Levelized Cost of Energy (LCOE). This study conducts a techno-economic sensitivity analysis on upgrading from conventional P-type to high-efficiency N-type modules within a fixed-footprint utility-scale project. Using RETScreen Expert, a model for a 50,000-unit installation shows that replacing 520 W PERC modules with 575 W TOPCon modules increases installed capacity by 10.58% (from 26 MW to 28.75 MW) and annual energy generation from 36.44 GWh to 40.29 GWh. The efficiency classes from 20.17% to 22.26%. A 2.09% efficiency gap functions as a force multiplier, resulting in disproportionately large advances in technical capacity, economic viability, and environmental sustainability. This shift could yield an NPV of approximately $4,470,000 and additional annual revenue of around $385,426, while mitigating an extra 38,000 tons of CO₂e over 20 years. High-efficiency modules demonstrate greater resistance to variations in electricity export rates and degradation factors, supporting the conclusion that N-type TOPCon offers optimal yield and efficient land use for policymakers and developers in land-constrained areas.