Photo: Bax Lindhardt

New lab completes teaching in solar cell systems

Solar energy
In June, 12 students from the three-week Applied Photovoltaics course were the first to use a new laboratory in which you can build and test full-sized solar panels.

Three groups of students are working hard with hammers and glue to make the best solar panel for a camping fridge.

“The winner will be the team that can deliver the coldest beer,” says Rasmus Nielsen, proudly showing off the result of his own group’s efforts: A solar panel with 36 solar cells in series mounted under glass. The team members have chosen the name Vive la France, even though there is only one Frenchman in the group, which also comprises an Italian and two Danes.

It is day three of the three-week Applied Photovoltaics course, which is held in the brand new DTU Fotonik laboratories at Risø Campus. The cabinets are full of boxes with solar cells, there is a large table with soldering equipment, and there is plenty of room for a class of students to try their hands at solar cell technology.

Over the next few days, their panels will be tested and characterized. Among other things, they will be taken to the imaging room, where electricity will be passed through them so they light up. You can thus use different diagnostic imaging tools to see any faults they may have. And for characterization purposes, there are two large appliances with powerful lights that will act as the Sun, so that you can measure how much energy they generate.

The new solar cell facilities completes DTU’s course package within solar cell systems:

"Obviously, the panels aren’t normally made by hand. But it’s nice to get to try it, because it gives you good insight into the industry and an idea of how the process can be optimized. And it’s also just so much fun to make something yourself."
Lasse Wahlgreen, DTU student

“In the spring, we had the theoretical Photovoltaic Systems course, in which students calculated components, systems, and installations, and now they will have a more hands-on experience in the physical world,” says one of the lecturers, Sune Thorsteinsson, study line responsible for Solar Energy on the Master's programme in Sustainable Energy.

Function and aesthetics
For Rasmus Nielsen, the course marks the end of the first year of his MSc in Sustainable Energy, while his teammate Lasse Wahlgreen is taking the course as part of a so-called flexible master, where you design your own continuing education with elements from the fixed study programmes. He teaches at the Copenhagen School of Marine Engineering and Technology Management and wants to upgrade his knowledge of fuel cells, solar cells, and electricity supply.

They are both thrilled with the new opportunities for a more holistic approach to solar cell technology, from planning to production to installation. Rasmus also plans to attend the Building Integrated Photovoltaics course in the autumn, which is held in collaboration between DTU Fotonik and DTU Civil Engineering

Another important purpose of the new laboratory is for the students to experiment with the integration of the solar cells—in collaboration with the industry—in various places where you would like to have direct access to the Sun’s energy, e.g. on the roofs of buildings, in lamps or sensors, and in connection with the Internet of Things.

“The standard panels available for purchase in, for example, China rarely fit in well visually in Danish construction. In the new laboratory, we can experiment our way to prototypes that will make the architect happy and produce enough energy at the same time. In this way, we can support a Danish industry. Denmark cannot compete with the cheap Chinese production of the cells themselves; but we can help develop and demonstrate systems that also meet the aesthetic requirements and thus possibly create a basis for a Danish production,” says Sune.

Vive la France
The three groups of solar panel builders have approached the task in slightly different ways. Two of them have chosen the most obvious model, where the cells are put together in four rows with nine cells in each. But Rasmus and Lasse’s group is attempting a landscape version in which the cells are fitted in six rows of six cells.

“Our panel may not fit onto a refrigerator door, but we wanted to try this solution, which we think is more aesthetically pleasing, and we expect it to have some advantages in terms of less shadow effect,” says Lasse, hoping that the panel will also work.

“The work is rather fidgety, and there is a lot that can go wrong. You can easily damage the thin solar cells or make mistakes when soldering. If even a single cell doesn’t work, the entire system dies. Obviously, the panels aren’t normally made by hand. But it’s nice to get to try it, because it gives you good insight into the industry and an idea of how the process can be optimized. And it’s also just so much fun to make something yourself.”