Solar PV industry is both technologically and capitally intensive, so manufacturers must have a keen market sense of smell and accurate strategic approach to survive. During the technology transformation period, having the two capabilities mentioned above determines a manufacturer’s long-term status in the industry.
Being an important international supplier of solar energy materials, Heraeus Photovoltaics Global Business Unit introduced a wide range of PV solutions including mainstream PERC, multi-Si cells, and next-generation technologies through Japan’s PV EXPO 2017. The company has further completed future energy blueprint and begin to move toward vertical and horizontal integration.
New solutions will eventually become the mainstream
Mono-Si PERC cell has entered the mainstream market in 2017, with the capacity doubling or tripling from 2016. Also, the cell conversion efficiency has reached 21.9%. Heraeus has participated in PERC technology growth throughout the whole process.
Heraeus already launched front and back-side silver paste for PERC cells in 2012 and achieved mass production in 2013, according to Dr. Weiming Zhang, Senior Vice President, Head of Global Sales & Head of Global Innovation for the Heraeus PV Global Business Unit. He forecasted that PERC will continue to dominate the mainstream high-efficiency market for two to three years and the whole world will be demanding for PERC cells.
Heraeus has further introduced the upgraded version of front-side SOL9641B and back-side SOL326 metallization silver paste as they are optimistic about the future demand of PERC cells. The former can be used for ultra-fine-line printing and low temperature sintering for PERC and BSF cells, while the latter has better adhesion and conductivity.
PERC technology works better on mono-Si cells. Meanwhile, the significant cost reduction of mono-Si wafers in 2016 has made mono-Si more cost-effective. The Chinese government has also driven high-efficiency demand through the “Top Runner Program”, pressuring multi-Si manufacturers. Therefore, multi-Si makers urgently need new technologies to win more market shares and black silicon has become the winner for the demand in technology. Zhang explained that black silicon has been active in the PV industry for nearly ten years. Two types of etching technologies have been developed for black silicon, which are dry and wet etching. Black silicon is expected to enter the mainstream market this year.
Following the rapid rise of black silicon, Heraeus can tell that multi-Si will still have certain shares in the market. As a result, the company came up with two solutions for multi-Si this year. One is front-side silver paste SOL9641Ax/Bx for knotless screen and another one is crucible coating “HeraGlaze©” for multi-Si ingots.
Zhang pointed out that since black silicon surface would be more uneven after etching, SOL9641Ax can lead to more concentrated printing knot, improving the quality of fine-line screen printing. As for SOL9641Bx, it can create a wider processing window after printing, optimizing PERC and other cell structure and power generation quality. Both products can keep the printing knot width within 26um, saving more paste while getting higher conversion efficiency.
|An image of a multi-si black-silicon cell that uses Heraeus's SOL9641Ax/Bx solution.|
Currently, it’s very rare to see paste solutions for black silicon in the market. Heraeus’s new product confirms the company’s strategic approach of “always a year ahead of the market.” In addition, the non-metallization paste product “HeraGlaze©” shows Heraeus’s effort in vertically-integrated solutions.
HeraGlaze©is a high purity SiO2 diffusion barrier coating. Adding HeraGlaze© to multi-Si ingot crucible will increase the quality of ingots, so the same ingot can get 4% extra wafer and up to 100.1% increase in conversion efficiency. Using HeraGlaze©with SOL9641Ax, black silicon texturing, and diamond-wire cutting will help multi-Si manufacturers to effectively increase their product C/P ratio.
Optimistic about N-type technology taking over the new generation
As PERC, which has been in development for many years, has entered the mainstream market, black silicon is expected to rise this year as well. Regarding the new generation technology, what is Heraeus’s thought? The direction can be seen from the company’s latest production line in 2017.
Heraeus introduced front-side silver paste for N-type cells and low temperature paste for heterojunction (HJT) cells at the PV EXPO 2017. Zhang explained that N-type cells are generally produced through high temperature sintering, but because N-type based HJT cells contain non-silicon materials, they can only be produced by low temperature (under 200°C) curing. That’s why Heraeus came up with different paste solutions. SOL570 paste for HJT is the second-generation product and allowed low temperature curing. It has excellent screen printing capability and adhesion to increase conductivity and HJT cell efficiency by 0.05%.
P-type PERC still has strong cost and technical advantages, while N-type is still a bit struggling with the maturity of cost and mass production technology. However, Heraeus is positive about the future of N-type since N-type technology will have more abundant equipment/production process to be put into R&D and at the same time the “Top Runner Program” continues to stimulate the technology upgrade.
On the other hand, judging from technology, power generation performance, and manufacturers’ investments, HJT certainly is a major option for the next-generation technology. Unfortunately, the popularity remains low due to the immaturity of capital and technology.
“Although HJT and N-type markets are not mature yet, we will keep working with our clients to provide more demandable products. Once the time comes, we are fully ready,” said Zhang.
Grows with the PV industry
Keeping Heraeus Group’s spirit for more than 150 years, Heraeus’s PV business views innovative R&D and customer service as the core of the business, accurately grasping trends and transforming them into products that are needed by the market. For the company’s vision in the PV industry, Zhang pointed out a clear goal: to improve cell conversion efficiency by 0.1% and above every year.
“We are committed to investing in the PV industry and promoting innovative R&D. Heraeus conduct customer survey twice every year, assisting our clients to improve their products and technologies and helping Heraeus to keep coming up with value-added services to satisfy clients’ needs,” Zhang explained.
Like other technology industries, PV technology is a continuous process of competition/replacement among generations. Enterprises with foresight must consider technology roadmap using generation as a unit and move forward with abundant R&D energy. For example, Heraeus announced a strategic partnership with a Chinese manufacturer – Jinko Solar in late-2016. Heraeus will be responsible for providing advanced metallization solutions, while Jinko Solar conducts experiment, linking innovation and production together.
This spirit of innovation also explains why Heraeus always choose to reveal the latest technology roadmap at the Japanese exhibition. PV EXPO is the world’s first international exhibition every year. In addition, Japanese clients pursue advanced technology and excellent quality, focusing on new technology R&D. Therefore, Japan is a good platform for showing new products.
Heraeus’s paste has a market share of 70-80% in the Japanese market, winning positive feedback from clients; the company has a fully functional team in Taiwan with advanced PERC technology capability, providing the most valuable solutions for key customers. Heraeus’s total shipment to China represents 70% and that makes China the most important market. The company set up R&D, manufacturing, technical support, sales and application service teams in Shanghai in order to meet local demand.
However, Heraeus didn’t plan to limit itself in the PV industry, but choose to move on to the next generation. The company believes that renewable energy will continue to grow, so they combined all kinds of renewable energy technologies and introduced an overall blueprint that no one ever did, including PV, wind power, hydrogen/fuel cells, and energy storage. Through the exhibition, Heraeus has clearly told the world: now and the future of PV and renewable energy industry.
(All photos and images are provided by Heraeus)