Interview: Uninterrupted cell production helps fast-track Indian solar manufacturing

pv magazine: Earlier this year two M10 Industries Kubus tabber stringer machines were installed by Emmvee in India. What has the performance feedback been so far? Are the machines consistently reaching the promised production rates of 5,500 cells per hour, and uninterrupted availability?
Maximilian Germann:
The machines were sold with the performance of 5,000 cells, but they have since been given an upgrade to reach the higher performance of 5,500 cells. Everything we do, we try to make it backwards compatible. So now those first two machines in the field are running at 5,500, and indeed are uninterrupted. Emmvee is very happy with the performance. They have been pleased with the equipment and the output, and especially the quality. The yield was much higher than expected. During a 72-hour stress test this year we reached a yield of 99.85% – those are outstanding numbers. Emmvee is happy, we are happy that Emmvee is happy and that the machines are performing well. Emmvee has been producing for more than 11 months now.

How vital do you feel good feedback from Emmvee will be in helping M10 to corner a larger share of the Indian market?
Recently we had a visit by a huge Indian company, who stated that without the reference the Emmvee they would have been afraid to choose M10 because our Kubus machine seemed to them rather sophisticated. Nevertheless, we gave them a demonstration how to operate it. So while the machine seems sophisticated – because it is – it is also not complicated to operate. It is a total new approach to the topic of cell connecting. The good feedback from Emmvee is helping us a lot to gain a foothold in the Indian market. They have been a really important reference for us.

It is interesting that you say the Indian company appeared almost daunted by how sophisticated the Kubus seemed. Do you think that is a wider issue of the Indian solar market, that there is a lack of experience and confidence?
This is not a problem only for the Indian market. They seem to be initially afraid of new technology, and innovation up to a certain point, but generally you see the same approach with U.S. or European companies, or Chinese firms that are considering our machines. They see the advantage of course, and the innovation, and once we show them how easy it is to operate they are confident.

Why do you think that the ability of the Kubus to offer such increased throughput convinced Emmvee to choose M10 Industries? What are the key benefits of being able to produce 5,500 cells per hour?
The most important point was not only the high performance, but also the quality of the output. All stringers to date have been designed for three busbars. That is where they come from, based on 15-year-old technology. M10 has a complete new way to approach alignment from busbar to ribbon, and avoid everything that was a pain for the module manufacturers. Most module makers have to stop the entire production for at least six minutes while doing a spool change. This is the first thing; you want to avoid these production interruptions. Secondly, we do not believe in any conveyor belts. The cell has to be aligned very precisely, and you cannot achieve that with some belts. That is why we produce everything sunny side down on carbon trays. We have a very precise alignment, and we only have three picks before the soldered string is on the glass. That means as little stress as possible for the cell, and because we are doing things in parallel, we have plenty of time to do the soldering. We have a comfortable soldering timescale. Everybody is in a rush, stressing the material, heating up very fast, we have the fastest machine in the world but because we are doing six strings in parallel, we do not stress the cell. These are the core technical points that Emmvee has witnessed.

Besides that, on a very small footprint we have delivered five times more performance than they had before. They didn’t need any new buildings or facilities; they just replaced old equipment with our machines and enjoyed the added benefit. It is not only about the number of 5,500 cells per hour, it’s also about the efficiency, and how companies handle their production. If you have the order backlog – and Emmvee does, it produces 24/7 – this machine is ideal because it is designed for continuous, uninterrupted throughput. Emmvee didn’t choose European or German technology, or even the fastest technology per se – they chose the most innovative concept.

Cost pressures exist right across the solar value chain, but are perhaps more intense at the manufacturing stage in countries such as India. With this in mind, do you expect India and other emerging markets to increase their interest in technology such as M10’s?
The Kubus is not chosen because of aesthetics, but because it’s an essential piece of equipment. Because at the end of the day considering the capex and cost of ownership, it’s the cheapest machine in the market. Non-interruption gets you around 30 MW more per year in output, at the same cost basis. You have to include the laminator regardless, and employ staff and have a facility, but it means you can use your line more efficiently. The cost pressure on our customers – we see the module market closely through our subsidiary SI Module – is very intense; Kubus does produce more efficiently simply because production can run as close as possible to 100%.

Furthermore, technology that was needed before is avoided in Kubus. We have the possibility to define the length of the last and first ribbon of each individual string, which means that ribbon cutting is not needed anymore. This saves on usage of material, up to €75,000 to €100,000 ribbon waste per year, and the usage of the material is as close as it can be now to 100%. The first important thing is to have an uninterrupted production, and the second point is get as much usage of the incoming goods as possible.

Regarding India, given its bold goals and proposed AD tariffs, does the Indian manufacturing landscape need to begin improving output, utilization and quality right now?
India has ambitious goals that are hard to reach. I hope that because modules coming in are clearly being sold at below production costs, this cools the market a little bit. They really need to start to invest in new equipment, and develop their own products for the market. Those solutions they have planned to make the energy supply more stable are really needed, but in the interests of India it would be good to produce as much as possible domestically: I hope there is some clarity from the government sometime soon, this will be a game-changer. Not necessary to have anti-dumping, but clarity is vital because business plans change with every uncertainty from government.

Can you explain how the Kubus is able to continue with throughput even during spool changing?
What Kubus provides is more of a supply network than a supply chain. A chain can be interrupted once one part is stopped. We put a focus on a high redundancy. If one part is not working for whatever reason, another part steps in and delivers. The machine is closer to Industry 4.0 than anything else in the market. We have lots of experience, and have done what we do for more than 20 years now. The concept of M10 was to ease the pain that module manufacturers have long felt during production. The main thing is the redundancy of the equipment itself. We have four independent working ribbon suppliers. For the full performance, only three are needed. During production the Kubus changes in the same step to another ribbon supply, and continues to produce. The empty ribbon supply just stops, the operator has all the time to get the spool changed, you can take the whole ribbon supply out of the machine, change the spool while the machine is running at 100% speed.

In low-cost labor markets such as India, does the Kubus lose any of the cost advantages gained by requiring only one operator per shift?
We do only need one operator to run the equipment, and simply they do not have to be there all the time. Because of this availability, operators have plenty of spare time. I oversaw operation of the Kubus during its first stress test in India and I got a little bored! There is not much to do, and it means people have time to do other things also.

Even in low cost labour markets, one person per shift means money. Every company is looking to save as much costs as possible while providing good quality. With Kubus, operators can focus their attentions elsewhere on the shop floor. Once the machine is set up and installed and implemented, there is not much to do besides refilling material.

What steps does M10 Industries take to ‘future-proof’ its machines? Solar trends and technologies can change quickly and unexpectedly, while the Kubus can for example, process half-cut cells, PERC and multi busbar cells, how do you accommodate the next cell trend?
The Kubus is made for the future. Everybody is coming from the past, from 10-15 years ago when the conveyor track systems were implemented. We have a totally new approach, and also on the materials side. We have a close concept with leading institutes such as Fraunhofer ISE, where we are talking about further developments, what is possible, what is coming up, what to prepare for. Kubus is prepared for up to six busbar, half-cut cells, PERC, and multi-busbar – which is possible but we do not see multi-busbar as having too much of an advantage. We can do it, but it requires more handling, which means that so far the main things our customers are interested in is half-cut cells. We are also future oriented in terms of gluing, which is also possible to integrate into the machine.

All technologies that are on the table, we are prepared for. We want to give customers the opportunity to be able to produce for the next ten years with our equipment. When four busbar was still the global standard, we already set our standard at five busbar, for example.

The +10% upgraded performance to 5,500 cells per hour was a recent development; can you explain briefly what steps were taken to achieve this?
The 10% upgrade was achieved by optimizing. It has not been only tuning the machine and making movements faster, but it’s been really a software and a hardware thing towards optimizing performance. Communication in the machine, in the system, is more efficient now. The focus initially was about being as safe as possible. When you start running with equipment on high performance, you begin with a little bit of extra security built in. Those movements and communication within the machine has now been optimized, and that enabled us to achieve 5,500 cells per hour.

In the future, what we want to do next is 6,000 cells per hour, which seems to be realistic, and we will continue to optimize the performance. In development terms we are in the final stage; there will be further improvement of performance over the next six months.

Besides that we will develop new features – higher trackability, higher connection, and the machine will get smarter with these developments. It is smart already, it can select the right ribbons, inform the operator what will be required in a couple of hours etc… there is a certain intelligence that will improve. We want to connect more to IT, and furthermore M10 will develop a wider portfolio. There will be some developments on the functionality of the equipment, as well as new products that will be introduced within the next 12 months.