The phasing out of renewable energy subsidies worldwide have led to unprecedented changes in the solar industry. From diamond-wire sawing to PERC, the recent application of various advanced technologies by PV manufacturers shows that there has been a tremendous leap in R&D and innovation.
Since the theoretical maximum conversion efficiency rate of traditional c-Si cells is only 29%, the probability of new and revolutionary efficiency-boosting technologies for c-Si cells has also become slimmer over time. After China launched the Top Runner Program in 2015, market demand and policy mandates have driven the development of a crop of next-generation cell and module technologies. Among them, HJT and shingled cells have commanded considerable attention within the industry.
Data analyses made by China Photovoltaic Industry Association (CPIA) show that wattage output of mono-Si modules reached 305W in 2018. The highest output of multi-Si PERC plus BS modules came to 295W in the same year, while HJT modules surpassed the former two by attaining a maximum of 320W. Research from CPIA also reveals that the shingled-cell design can provide an additional output gain of at least 20W. As the term suggests, the shingled-cell template allows seamless connection between cells in the module by stacking them together.
Technology and production costs hinder the development of HJT cells
As of now, more than 20 PV manufacturers have announced that they engaging in either the R&D or the volume production of HJT cells. Most of them, however, have yet to move their HJT products past the trial or pilot-scale production phase. The global production capacity for HJT cells is projected to reach 6.24GW in 2019, says the latest edition of Market of Advanced PV Technology Report published by EnergyTrend, a division of TrendForce. Also, four of the current top five suppliers of N-type cells are producing HJT cells.
CSC Financial recently made a comparative analysis of the costs of different cell and module technologies in China. The analysis, which is based on the LCOE of a 200MW power plant, finds that the initial investment cost of HJT modules is about 10% higher than that of PERC modules. In terms of performance, HJT modules offer higher efficiency and low susceptibility to degradation issues. These advantages ultimately allow HJT modules to not only surpass PERC modules in the amount of electricity generated within the operational lifespan but also to achieve near parity with PERC modules in LCOE.
Source: This figure is taken from EnergyTrend’s Market of Advanced PV Technology Report.
Although HJT edges out PERC in many aspects, the development of this technology is constrained by several factors. Higher production cost, slow progress on domestic production (in China), and fierce competition from existing technologies are some of the reasons why HJT has not been widely adopted. In particular, the manufacturing HJT cells requires equipment that exclusively caters to this technology. Most of the existing cell production lines cannot be modified to incorporate the fabrication process for HJT cells. Hence, HJT during the course of its commercialization is going to be in a weaker position vis-à-vis PERC, which now has around 50% of the global market share in PV cells.
Table 1: Key Processes in Production of HJT Cells and Related Equipment Providers
|
Process |
Equipment |
Main Equipment Providers |
Progress in Domestic Manufacturing (China) |
|
Wafer Texturing |
Cleaning Machine |
YAC, Singulus, S.C New Energy Technology |
Mainly reliant on foreign equipment but domestic counterparts are entering the market |
|
Amorphous Si Deposition |
CAT-CVD, PECVD |
Ulva, MB, AMAT, Jusung, S.C New Energy Technology |
Domestic equipment is in R&D and could enter the market in 2019 |
|
TCO |
RPD, PVD |
Sumitomo, MB, Von Ardenne, AMAT, Ulvac, Jusung, S.C New Energy Technology, Archers Systems |
Domestic equipment is in R&D and could enter the market in 2019 |
|
Electrode Formation |
Screen Printing Machine |
Micro-Tech, Baccimi, Maxwell, Folungwin |
Mainly reliant on foreign equipment but domestic counterparts are being produced and deployed |
Source: Information provided by S.C New Energy Technology and GS-Solar.
While the market growth of HJT products is weighed down by challenges, the solar industry appears to be keener on adopting the shingled-cell design. At the 2019 edition of PV Expo Japan, a total of 16 manufacturers put their shingled modules on display. These products include large-size modules, small-size modules for residential generation, modules containing P- and N-type cells, etc. One particular module that was on display during the PV Expo featured shingled HJT cells and boasted an output of 435W.
Although shingled modules show enormous market potential, their availability is limited by the high cost of related processing equipment and patent restrictions. Whether this design template can enter large-scale commercialization in the near future is still debatable. Half-cut cells, which are similar to shingled cells but allow gaps between the interconnections of cells, have been much popular in the industry this year. Compared with the half-cut process, the shingling process lags behind in terms production capacity and production volume. EnergyTrend currently estimates that the global production capacity for shingled modules will reach 14GW in 2019, and that the market share of the technology will also grow to nearly 10%.
Figure 2: Forecast of Global Production Capacity for Shingled and Half-Cut Modules, 2018-2022
Source: This figure is taken from EnergyTrend’s Market of Advanced PV Technology Report.
(The content of this article is provided by EnergyTrend. Photograph: Pixabay.)