- While the cell efficiency of HJT is increasing and also technology is widely used in several configurations
- Several leading market players are focussing on HJT and module efficiency, with processing half wafers of large formats being already a trend
- With all advantages of the technology, HJT module producers are starting to address the utility segment as well
High cell efficiency is a key motivating factor to opt for HJT cell technology as that’s the major level to decrease cost on the module level. Due to its superior passivation quality, HJT technology can attain very high Voc of above 750 mV. PV producers, equipment makers and research institutes have announced different efficiency levels for their HJT cells. The most recent record was announced by LONGi in November – the company designed a HJT solar cell with an efficiency of 26.81%, the world’s highest level for a silicon solar cell, and breaking a 5-year old record from Japan’s Kaneka (see LONGi Breaks Long-Time Silicon Solar Cell Record).
HJT technology has also made significant progress at the module level. Until last year, HJT modules paled in front of PERC in terms of power output, as the technology had not been scaled to larger wafers. In the meantime, several manufacturers have adapted the technology to larger wafer formats and companies have also started processing half wafers. In June 2022, Huasun from China, for example, released its Himalaya G12 series of modules targeting to become the 1st manufacturer to ship over 1 GW of HJT modules (see China PV News Snippets). In October 2022, Huasun introduced its Himalaya M6 series 120 half-cell full black lightweight heterojunction solar module with up to 400 W output and 21.96% efficiency for the residential rooftop market (see New 400W HJT Solar Module For Residential Segment). Moreover, market leading cell vendors like Tongwei have also begun selling HJT cells.
HJT technology not only results in high efficiency at the cell and module level tested indoors, but the technology also performs well in real-world operating conditions. HJT offers the best bifaciality of close to 90%. It has a low temperature coefficient of -0.26%/°C compared to over 0.4%/°C for PERC. However, HJT has just started making inroads into high-volume production and its deployment is yet to pick up. Due to its higher manufacturing costs, HJT has been primarily considered a premium product and mainly aimed at the rooftop segment, which is a common target for premium products.
In that regard, Meyer Burger is also integrating HJT into rooftiles. At the recent Intersolar Europe trade show, the company presented the optimized version of its tile solution introduced in 2021. The new variant, covering the length of the rooftiles, offers roofers maximum flexibility as they are no longer bound to a fixed substructure dimension. Attractive aesthetics with a very high energy yield as well as simple installation and maintenance come on top. Now it remains to be seen how this product will be received in the market, as such small tiles need to priced even higher than standard HJT modules.
Meyer Burger also presented at Intersolar Europe a new module with 1,500 V system voltage to enable larger strings in series as it wants to address also larger rooftops in the C&I segment.
The first HJT modules can be now also seen in utility-scale solar plants. Huasun has started supplying its HJT modules for a 350 MW solar park with trackers in Europe. All the advantages discussed above enable the technology to be competitive even in utility-scale applications, claims Huasun. Risen is also aiming to address the needs of the utility segment with its latest Hyper-ion. As this segment is much more capex sensitive than residential rooftops, it will be also very interesting to see how HJT performs for this solar application as HJT module prices are much higher today. However, Meyer Burger was recently able to sign an impressive multi-GW HJT module supply deal in the US for products that will be used in utility-scale applications (see 3.75 GW DESRI Order For Meyer Burger In US).
The text is an updated excerpt from the 3rd edition of TaiyangNews’ Heterojunction Technology 2022 report, which provides an overview on recent HJT developments as the technology is entering the GW scale production level and can be accessed free of charge here.