Staying Ahead on the Solar Innovation Curve — Dr. Hongbin Fang, Director of Product Marketing at LONGi Solar Talks About the “Technologies Behind the Innovations”

PVTIME - LONGi Solar has recently released the specs on its upcoming contribution to the ultra-high-power 500W-plus solar module market, the Hi-MO 5. The new module, which is due for commercial production in September 2020, is a high-power product ideal for utility-scale power plants. Dr Hongbin Fang, Director of Product Marketing at LONGi Solar talks about the objective and innovations behind the Hi-MO 5 technology, its applicability and key differentiators, timeline for commercial availability, and customer feedback.

Dr. Hongbin Fang, Director of Product Marketing at LONGi Solar talks about the “Technologies Behind the Innovations”

What have been the key highlights of LONGi’s
product development strategy so far in 2020?

LONGi Solar, at its core, is a technology- and
innovation-driven manufacturer and the global PV market is rapidly moving
towards high-power modules to reduce system costs and initial upfront capital
investment. Our product development strategy has always been based on
technology advancements and innovations that help our customers to achieve
better system economics and lower LCOE.

Towards this end, the most significant
breakthrough in 2020 has been the launch of Hi-MO 5 series of modules which are
best suited for utility-scale solar applications. Our innovation logic for this
new series of modules is to look at every aspect of PV project deployment with
holistic view and find best overall solution: not only ingot, wafer, cell and
module manufacturing processes, but also module deployment processes, such as
transportation, installation and system integrations. Given the significant
evolution of developing utility-scale PV projects globally, the primary
objective of developing Hi-MO 5 series is to meet higher-quality and greater
efficiency demand of the industry and to reduce the LCOE of a solar power
plant. We are very excited that the introduction of Hi-MO 5 modules will enable
our customers to dramatically reduce their PV projects BOS cost.

Can you elaborate on the key innovations on the
downstream side of solar value chain?

Hi-MO 5 is based on M10 gallium doped monocrystalline
wafers and uses smart soldering technology. The 72c module power reaches 540W,
with an efficiency of more than 21%.

M10 is a new solar wafer size standard at 182mm
width. This standard is established with thorough studies across the whole PV
module manufacturing and deployment processes. One of the key limiting factors
is opening height of 40’ container commonly used to ship modules across oceans.
With modules packed at landscape configuration and double stacked inside 40’
container, the module width is limited at about 1130mm. and each solar cell
width at 182mm. In June, LONGi and six other leading solar cell and module
manufacturers came together to establish this new industry standard of wafer
size M10. With M10 wafer size standardization, all players through the value
chain now have a common platform to develop and optimize their individual
equipment and process to realize optimum performance and lower cost. This
standardization will help to deliver better value for our customers.

In 2020, LONGi and Shin-Etsu Chemical entered into a global patent agreement on gallium-doped technologies, which allows applications of LONGi’s products with gallium-doped technologies. LONGi optimized gallium-doped M10 standard silicon wafers (182mm) to produce a P-Type Mono PERC module with the lowest light-induced degradation (LID), improved attenuation performance and high power, all of which helps in delivering better values to our customers. To be specific - the first-year power warranty is an industry-leading 98% and linear annual attenuation is within 0.45% through 30 years lifetime. While gallium-doped silicon wafers are more expensive, we have been able to address this challenge through advances in technology and production scale.

Further, smart soldering has been used to increase
module conversion efficiency – in this case by 0.3%. Our proprietary technology
uses “integrated segmented soldering ribbons” that maximizes light capture and
reduces the gap between solar cells. It helps reduce the tensile stress of the
cell for better reliability.

What are the other key features of these modules
and in which ways would a utility-scale project developer benefit from using
Hi-MO 5?

The working current of LONGi Hi-MO 5 module is
about 13A. Including bifacial gain, the operating current remains within the
maximum input current range of the inverter, with no power generation losses.
The module length is compatible with 1P and 2P horizontal single axis tracking
systems.  We will continue to work with inverter and racking companies to
ensure compatibility with Hi-MO 5 modules.

Hi-MO 5 bifacial modules continue with “double
glass with frame” design that provides sufficient strength for high load
capacity and proven long-term reliability performance. The strength of the
frame negates the need for a cross-beam, helping avoid any shading losses at
the back of the module.

Comparing to Hi-MO 4, Voc of Hi-MO 5 modules are
kept the same, which enables same number of modules per string. With each Hi-MO
5 module is 20% higher power than Hi-MO4, per string power output is increased
by 20%, which will significantly reduce both mechanical and electrical BOS
costs. With power rating per module is 20% higher on Hi-MO5, significant
savings can also be realized on installation labor.  By estimation, Hi-MO
5 modules can save our customers US$0.01-0.02 /W on BOS cost comparing to
Hi-MO4 modules, bringing about lower LCOE and better value. LONGi has partnered
with more than 20 customers globally to verify the BOS savings, lower LCOE and
better performance of Hi-MO 5 modules in real world applications.

Further, Hi-MO 5 will be backed by competitive
warranties and LONGi Solar's commitment to high quality customer service.

What has been the primary response of LONGi’s
existing and potential consumers to the new series? Which markets are likely to
be the early adopters of this technology?

We have seen an overwhelming response from our
customers across the world for the Hi-MO 5 series. While the production is scheduled
from Q3 2020 onwards, we are already beginning to receive tremendous queries
and orders which is a very positive sign.

As far as the markets are concerned, the product
is likely to witness high uptake in large utility projects across regions due
to its widespread suitability and cutting-edge benefits.

What is the company’s target regarding Hi-MO 5,
both in terms of production capacity?

The module production capacity of LONGi has
increased 20-fold from 1.5 GW in 2015 to 30 GW in 2020. Hi-MO 5 will be
produced in volume and receive IEC/UL certification in September 2020. Its
production capacity will reach 12 GW by end of 2020, guaranteeing a stable
supply for global customers.

LONGi has been leading another key initiative
pertaining to wafer size standardization. What is the idea behind that and what
has been the progress so far?

For a long time uptil 2018, M2 wafers measuring
156.75mm were widely seen as the industry standard, representing more than 90
per cent of the market. The trend of larger photovoltaic
modules began in the second half of 2018. At that time, monocrystalline
modules using 158.75mm silicon wafers first appeared, together with silicon
wafers with specifications of 157.4mm and 161.7mm, all larger than the
mainstream M2-156.75mm wafer.Since 2019 however, manufacturers have begun to
see benefits in increasing wafer sizes, leading ultimately to modules rated at
over 500 W appearing on the market. Given the compatibility with existing
100GW cell production capacity, M6 wafers of 166mm were duly launched in May
2019 by LONGi. Hi-MO 4 based on M6 wafer
is suited for full scenarios such as C&I, large utility projects, through promotional
activities, the downstream power plant investment and design sector
recognized the system side value brought by the increase in
wafer size.  With the absence of a common standard, companies have adopted
wafers of varying sizes, resulting in an increase in manufacturing costs
throughout the entire industry supply chain, including wafers, cells, modules
and auxiliary materials such as glass. This situation has complicated
customers’ selection processes, the installation of photovoltaic systems and
coordination between the industry’s upstream and downstream sectors. To
effectively address these issues and accelerate the industry’s efficient and
standardized development, LONGi led a pack of seven solar manufacturers to
establish the new M10 silicon wafer standard size (182mm x 182mm). Besides
LONGi, the group includes JinkoSolar, Canadian Solar, JA Solar, Runyang Yueda
Photovoltaic Technology, Lu’an Solar Technology and Zhongyu Photovoltaic
Technology. Our initiative to promote standardization will help optimize the
use of resources and promote the photovoltaic industry’s continued healthy
development. It will be good to have more manufacturers join the initiative.