A study in Kagoshima, Japan has shown that the latest generation of TOPCon modules has surpassed p-type BC modules on energy yield during the initial month of a 1-year testing period, with an average yield of 2.22% and maximum of 6.95% higher than their p-type counterparts.
Background of the project:
Most PV manufacturers are now underway with the switch to n-type, primarily TOPCon, technology. Over recent months, the PV industry has debated the future technical route of XBC, with manufacturers promised more rated power and front-side efficiency due to the absence of grid lines.
Numerous studies have already been carried out, with a recent study by TÜV NORD confirming an average 2.22% (up to a maximum of 6.95%) gain for TOPCon versus p-type BC in normalized energy yield (energy generated per unit of capacity) over an initial one month period between September 12 and October 11 in Kagoshima, Japan.
Project Introduction：
Three module types were installed at the site: An n-type TOPCon module with rated power of 575W from Jinkosolar, a 580W p-type BC module and a 605W n-type BC module. The test installation comprised two modules of each type, installed on fixed tilt racking of 20°, 1.2 metres above ground. The sample specifications were as follows:
Test Results：
The initial power of each sample was measured using SAT without spectral correction. Power output data was gathered with a high-precision CR1000X system for individual components. The TOPCon module generated 136.86 kWh/kW，the p-type BC 133.87 kWh/kW and the n-type BC 129.98 kWh/kW. Due to its higher bifaciality and lower temperature coefficient, the TOPCon module achieved a yield 2.22% higher than its p-type BC equivalent and 5.29% higher than the n-type BC, once normalized based on each module power rating.
The Jinko TOPCon module also achieved the highest performance ratio of the three. Performance ratio compares the actual energy yield to a calculation based on power rating and weather conditions. TÜV NORD measured a 94.19% performance ratio for the TOPCon module, with the other two trailing slightly behind, 91.99% for p-type BC and 89.29% for n-type BC. The future data validation plan will involve swapping channels and component installation positions to minimize systematic differences.
