Table 1. IEC standard algorithm vs inverter manufacturer recommended algorithm (calculated when minimum temperature is set to zero) Tiger Pro 530 W
Factory 2 500 W
Factory 3 500 W
49.5
51
51.5
Number of components per string (based on IEC standards)
28
27
27
Number of components per string (calculated according to the inverter manufacturer)
29
28
27
Open circuit voltage (V)
Table 2. BOS cost comparison (assuming that the model and cost of the inverters are the same, the first year of the project generates the same amount of electricity) 120 MW Vietnam project
Tiger Pro 530 W
G12 500 W
M6 445 W
Configuration information First year (MWh)
200 200
200 200
200 200
Number of modules per string
30
29
30
Number of inverters
518
518
518
System voltage (V)
1500
1500
1500
Total number of modules
226 416
240 000
266 667
Total number of strings
7548
8276
8889
+1.85%
+2.31%
BOS cost BOS cost (%)
0
Table 3. Tracker cost comparisons between two modules provided by the mounting system manufacturer (moderate and high wind pressures) Module length (mm)
Number of modules per string
2230
28
2267
28
Recommended mounting system layout under moderate high wind pressure
Total power
Cost per watt
Power level
2 × 28 (outside) and 2 × 42 (inside)
44 520
0.03911
530
2 × 28 (outside) and 2 × 42 (inside)
44 520
0.04038
530
Table 4. Simulation results of both PV plants in Vietnam with different inverters
Component model Number of components Number of inverters Hours of annual power generation
26 A maximum input current inverter
30 A maximum input current inverter
Tiger Pro bifacial 530 W
Tiger Pro bifacial 530 W
16 200
16 200
32
32
1650
1694
60 ENERGY GLOBAL SUMMER 2020
corresponding wind and snow loads, which indirectly reduces the cost of the fasteners for the mounting system. According to the model provided by the mounting system manufacturer, the cost of a single watt for the mounting system is inversely proportional to the size of power in low wind pressure areas, thus the higher the power of modules, the lower the cost of a single watt for the mounting system. However, in high wind pressure areas, the cost of a single watt for the mounting system is positively related to the length of modules. Comparing Tiger Pro with modules from other manufacturers at the same power – according to the data provided by the tracker mounting system manufacturer – it is evident that although the component panels have the same power, the cost per watt of the mounting system also varies.
High compatibility between bifacial modules and inverters Following multiple experiments, it is known that the shortcircuit current and working current of bifacial modules are much higher than those of mono-facial modules. At present, the maximum input current of maximum power point tracking (MPPT) of mainstream string inverters is 26 A, but when the back gain is more than 30% and the solar irradiance is very good (>1000W/m2), the output current of the modules may be more than 13 A. If one MPPT of the inverter connects two groups of strings, the output of the modules will be lost. To bring higher power generation and lower power cost to clients, JinkoSolar has been in close communication with several mainstream inverter manufacturers to promote the launch of high current inverter products in response to JinkoSolar’s bifacial modules with high performance.
Higher production processes and product quality From the testing in Vietnam, the company received the results seen in Table 4, from which it is clear that the inverters with high input current will be better optimised on the power generation of Tiger Pro products. JinkoSolar’s modules have been rated as highly bankable PV module products in the industry, due to the high standard production process. In today’s 1500 V system era, high-quality module products have lower mismatch rates between groups and modules in long strings, which makes it easier for inverters to track to the maximum power point, especially in power stations that have been running for many years. In summary, JinkoSolar’s Tiger Pro has demonstrated advantages in both cost reduction and compatibility on the system side, and this series of products may become one of the mainstream module selections in the new industry.
Technology components impacting LCOE Along with the subsidy-free grid parity policy’s release of the National Development and Reform Commission and National Energy Administration in China, PV module power is upgrading unremittingly to meet the demand of the era
