Electrifying contacts

The energy crisis is enabling a comeback for the European solar industry. Good for companies such as Teamtechnik. The Dürr subsidiary builds machines that interconnect individual solar cells at lightning speed so they can be put together to create large modules.

Metal frames are gliding on conveyor rails, lights are flashing, and vacuum grippers are dancing in a uniform rhythm. A layperson would scarcely notice what tasks are being completed by these complex machines, built by Teamtechnik in the German town of Freiberg am Neckar. Only the solar cells, stacked in the factory building for demonstration purposes, indicate what type of sector the buyers come from.

The Dürr subsidiary produces specialized machines for the solar industry. These so-called stringers interconnect individual solar cells. The strings thus created are later assembled to produce complete modules and can eventually be found in photovoltaic systems on roofs and on open land. “Since solar modules are needed in large quantities, production must be fast and highly automated,” says Thomas Fischer, Head of Mechanical Design & Technology Development.

The machines built by Teamtechnik help to meet the rapidly growing demand for solar technology, since photovoltaics, along with wind power, are crucial in achieving climate targets. In addition, solar power can be harnessed more and more cost-effectively. This is partly why global generating capacities increased tenfold between 2012 and 2022. The sector anticipates a further increase, with figures expected to double by 2025.

In 2005, Teamtechnik launched the first stringer. Two years later, the company was able to produce the machines in series. It was especially the growing Chinese solar industry that was keen to get its hands on the technology from Freiberg am Neckar. “In 2011, we were world market leader,” says Roßkopf. Back then, five machines would leave the company each week. Stringers made up around 60 percent of Teamtechnik’s sales.

Then, competitors in Asia started building these specialized machines themselves, while in Europe government incentives for the solar industry were being reduced. Even though sales of stringers declined, Teamtechnik was not discouraged and continued this business on a small scale.

Since then, a new generation of solar cells has come onto the market. The cells generate more electricity per square meter, with the downside that they cannot tolerate the 200 degrees Celsius necessary for soldering. Together with the Fraunhofer Institute for Solar Energy Systems ISE, the Teamtechnik experts have found a way to connect solar cells using an electrically conductive adhesive. Now, in simple terms, new machines apply the adhesive in exactly the right places with the help of a fine-mesh screen.

This kind of innovation is well received. Around 20 of the new machines are going to a customer who is putting a solar module factory into operation in Italy in 2023. Next year there is the possibility of more large orders. Roßkopf is optimistic. “The Western solar industry is on the rise again.”

This has several reasons. For one thing, the oil and gas shortages are creating a new tailwind for the solar industry. In addition, companies are seeking to become independent of suppliers from other parts of the world. Furthermore, the United States is currently pumping billions of dollars into the renewable energy sector to fight inflation and boost its economy.

Roßkopf reckons that the shift in the energy world will continue to have a positive effect on Teamtechnik’s business. This is because Teamtechnik also manufactures assembly and test systems for batteries, which are used, for instance, in electric vehicles and home energy storage. This means the company is involved in important points of tomorrow’s energy system.

It is thus already possible for solar power not only to be fed from the roofs of residential buildings into the local grid, but also to be stored locally in the basement or sent directly to the electric car in the garage. The car battery could, one day, even be used as a storage device to lighten the burden on the national grid.

It is not only the energy sector that has come to rely on the Dürr subsidiary’s products, but also the aerospace industry. Satellites launched into space obtain their electricity from solar sails, i.e. photovoltaic systems. One thing that Roßkopf is particularly proud of is that the solar modules they contain are increasingly manufactured using machines from Freiberg am Neckar.