TaiyangNews talked to Linyang’s top management members - CEO Pei Jun (photo), CTO Dr. Xu and module division director Lu Fei - about its expansion plans and why they focus on n-type bifacial solar technology. (photo credit: Linyang)
Linyang Solar Technology appears to be a new PV manufacturer, but the Shanghai-based company has strong roots that reach back to the early days of solar module production in China. While focusing on the solar system business for the last few years, in 2016, Linyang started a module production that is 100% bifacial.
Originally, Linyang is an electricity meter company, which is one of the biggest in the world. It was founded in 1995. From 2004, Linyang started to invest in PV. Known as SolarFun, it the first Chinese PV company listed at NASDAQ. In 2010, Linyang decided to sell off the company to Hanwha Group and step out of PV.
With the attractive solar support policies issued in China, in 2013, the company decided to return to the PV industry, but this time downstream, focusing on distributed PV power plant investments. It has installed 1.5 GW and has invested about 8 billion CNY in the downstream part of the solar value chain, which includes systems investment, EPC, financing and operation and maintenance.
As a downstream PV system provider, Linyang realized that only advanced solar cell and PV module technology can further improve the performance of solar systems and reduce LCOE ultimately. For this reason, Linyang decided to set up a new and advanced solar cell and module factory in 2016 to produce high performance bifacial products for the PV market.
TaiyangNews: Your company has a long history in solar. Can you give us a brief overview how you have become a bifacial module manufacturer?
Linyang: Originally, Linyang is an electricity meter company, which is one of the biggest in the world. It was founded in 1995. From 2004, we started to invest in PV. Our company, known as SolarFun, was the first Chinese PV company listed at NASDAQ. In 2010, Linyang decided to sell off the company to Hanwha Group and step out of PV.
With the attractive solar support policies issued in China, in 2013, the company decided to return to the PV industry, but this time downstream, focusing on distributed PV power plant investments. Since 2013, we have installed 1.5 GW. Linyang has invested about 8 billion CNY in the downstream part of the solar value chain, which includes systems investment, EPC, financing and operation and maintenance.
As a downstream PV system provider, we have realized that only advanced solar cell and PV module technology can further improve the performance of solar systems and reduce LCOE ultimately. For this reason, Linyang decided to set up a new and advanced solar cell and module factory in 2016 to produce high performance bifacial products for the PV market.
TaiyangNews: What was the reason for choosing n-type over p-type, which clearly dominates cell manufacturing today?
Linyang: First, n-type has natural advantages compared to p-type, such as no LID, low temperature coefficient and higher cell efficiency, which will provide a better module output and performance. Second, n-type has a fantastic bifaciality that will gain extra power from the module backside. Considering module power and system performance, n-type modules will give us a lower LCOE, which will translate to a better IRR for investors.
TaiyangNews: You mention the low LCOE and high IRR of n-type products. What’s your strategy with bifacial in terms of markets?
Linyang: The focus of the PV market in China has swapped from large-scaled solar plants to distributed solar systems, such as rooftop solar, farm installations, fishpond PV systems. For those distributed solar system, there is a limited space for solar panels. A higher power output is the only way to have a better IRR. Already today, our bifacial modules have a 10 to 30% bifacial gain from the backside. In order to have even better bifacial PV system solutions, Linyang created a research institute last year which mainly focusses on the development of innovative bifacial PV system designs. As a part of our company strategy, the creative bifacial PV system design will further improve the power performance of our bifacial module to reduce LCOE and BOS.
TaiyangNews: How do you want to differentiate from other solar companies producing bifacial technology?
Linyang: We have adopted a different cell process technology for producing bifacial cells compared to other solar companies, which is more cost effective. This technology is more mature for mass production and will give us a better mass production performance.
TaiyangNews: The bifacial concept is known for several years; what has really changed that now the PV industry is increasingly evaluating bifacial technology?
Linyang: First, we have been seeing a market trend with costs of n-type wafer coming down, and now n-type solar cell technology is mature, including process steps, manufacturing equipment & materials. In fact, the cost of n-type solar cells and module is competitive. More and more solar companies are embracing this technology. Second, we have the Top Runner Program in China, which encourages advanced PV technology and asks for high power PV modules from the market. Now, more and more system designers have accepted the technology and are willing to use bifacial modules for their systems.
TaiyangNews: What is your current production capacity for n-PERT?
Linyang: We have a cell and module capacity of 700 MW – and the entire capacity is bifacial. Actually, we only do bifacial.
TaiyangNews: What are your expansion plans?
Linyang: In 2 to 3 years, we have plans to expand to 2 GW total capacity.
TaiyangNews: Are you working on any bifacial projects? And how many in the pipeline?
Linyang: As I mentioned, we have the Top Runner Program in China, and we have a 50 MW project in the program. We are installing the system right now and will finish in a couple of months. After this, we will aggressively promote our products in overseas markets like Europe, Japan and Australia. This 50 MW system will become a good demonstration site for selling our modules.
TaiyangNews: Let’s talk a bit about technology. As you are focusing on n-PERT, how many process steps are you adding to standard Al-BSF line with your processing?
Linyang: If we compare with p-PERC, the process steps are mostly the same. For PERC there is aluminum oxide, they have the lasers, we don’t have these. We have boron diffusion, which is roughly the same costs as for aluminium oxide.
TaiyangNews: Are you working on any specific technology improvements at the cell level to reduce costs or increase efficiency?
Linyang: At the cell level we are working on heterojunction technology. At the module level we are working on the multi-busbar approach, which tremendously reduces silver paste consumption by up to 40%. In addition, we also evaluate thinner wafers as a cost reduction enabler.
TaiyangNews: And at the module level, are there any major changes required for your n-PERT bifacial products?
Linyang: The major change is the double glass structure without aluminum frame compared to a conventional single glass PV module structure. In addition, the double glass PV module comes with a different encapsulant, which was changed from EVA to Polyolefin Elastomer (POE) to prevent moisture to penetrate into the PV module, which is the main reason for module failure.
TaiyangNews: Is there any special care required for interconnection?
Linyang: In terms of interconnection materials, it is the same as for conventional modules. But in terms of module layout, there is a different internal circuit design in our bifacial modules. However, if you look at a full size module, there is no change needed. For us there is, because we use half-cut cells. Our entire module line is using half-cut cells. This improves our cell-to-module (CTM) ratio and improves the module power at least by 5 W. The CTM for mono solar modules in China is about 96 to 97%. With our modules we are already at 98%. This is with half-cut cells and special optical design. We also make some unique design and optimized optical mesh on the glass. We have very ambitious plans to go to 99%. We worked a lot on glass and encapsulant materials.
TaiyangNews: Coming to module protection based on glass. What is the glass thickness you are using?
Linyang: It is 2.5 mm. This is currently the standard, but we would like to go to much thinner glass like 2.0 or 1.8. But now thinner glass technology is not mature and very expensive as well.
TaiyangNews: Isn’t glass more expensive than using backsheets?
Linyang: The price is actually the same, if you are using 2.5 mm semi-tempered glass.
TaiyangNews: An alternative would be transparent backsheets. Is it true that transparent backsheets have lower NOCT?
Linyang: Mono cells have low temperature coefficients, that’s not specific to transparent backsheets. And at some installations sites this may not be a problem, such as floating PV.
TaiyangNews: What about standards? How are you accomplishing IV measurements for bifacial cells and modules?
Linyang: Currently, there is no standard measurement method for bifacial cells and modules. We along with few other bifacial producers who have products in the market are trying to generate a standard on how to define the rear side power. By the end of this year, this will be decided.
TaiyangNews: What is the front and rear efficiency you have attained at module level with your bifacial technology?
Linyang: At module level we have 18% efficiency and bifaciality of 80% to about 90%.
TaiyangNews: Do you recommend any optimization for mounting bifacial modules, like increasing height or any other changes to the installations sites?
Linyang: We have our own institute for installations. They are working on different solutions for bifacial modules compared to conventional monofacial modules.
TaiyangNews: You already mentioned that glass is not more expensive than backsheets. What are your total production costs?
Linyang: Currently, we have the same cost level as p-PERC mono modules. But we are working on multi-busbar technology, which will give us a more cost-effective solution. Once implemented, the cost of our product will be lower than for p-PERC mono module.
TaiyangNews: Thank you for the interview.
The interview was originally published in TaiyangNews Bifacial Module Technology 2017 Report, which can be downloaded free of charge here