Students Develop a Device to Measure Water Quality in Africa

A team in the Faculty of Electrical Engineering at the University of Bremen has been awarded the first prize in COSIMA (Competition of Students in Microsystems Applications), the largest German competition for students of microsystems technology. The five students won the prize for their work on developing a measuring device that can be used to check the quality of water in developing countries.

The students, all aspiring engineers, came up with the idea on their own and spent a year developing it in their spare time. One of the group, Theodor Hillebrand, had learned about a cost-effective water treatment method used in the equatorial regions of Africa, Indonesia and Latin America through his involvement with the Technischen Hilfswerk (German agency for civil protection). He found out that the World Health Organization recommends the use of the so-called SODIS method (Solar Water Disinfection) to the poor populations in developing countries who have only restricted access to clean drinking water. By filling PET bottles with water and laying them in full sunlight the water becomes drinkable. This is because after about six seconds or so the UV rays kill off the bacteria contained in the water. The SODIS method helps to prevent diarrhea infections and saves lives.

When is the water really free of harmful germs?

However, the method is not foolproof. For instance, how is it possible to know when the water is completely free of bacteria? “This was the reason we started to think about developing a measuring device to show when the water is really ready for drinking”, says Theodor Hillebrand, the man who came up with the idea. He then started to put his idea into practice with the help of fellow students Yannick Auth, David Horch, Maike Taddiken and Konstantin Tscherkaschin. The members of the team were already known to each other as they all act as tutors in the basic lab of electrical engineering in the NW1 building. First of all, they set about collecting relevant information. Among other things they recruited the expertise of a university biologist. They then put together everything needed for subsequent lab tests. “That already took up most of a table top”, recalls David Horch.

Sponsors convinced

They also had to find a way to finance the development of practical prototypes. These would have to be cylindrical in shape and compact enough to fit through the neck of a bottle. The committed group of young people managed to overcome this obstacle, too. Indeed, they convinced no fewer than 25 people to support their idea. “We didn’t just have a gadget in mind, but a more sophisticated concept that could help people over the long term”, explains Yannick Auth. The main sponsors included the Kellner & Stoll Stiftung für Klima und Umwelt, swb, Beta Layout Electronics, and Kaefer Isoliertechnik.

User-friendly for children and people who can’t read

What was so difficult about developing the measuring device? “Everything”, says Theodor Hillebrand with a laugh. And the final product is really quite impressive. Flexible solar cells inside the small transparent tubes called Scipios (Scientific Purification Indicators) regulate the supply of energy. They incorporate tiny measuring devices and condensers that are fixed on a printed circuit board. And Scipio even has an integrated position sensor to ensure the bottle is lying correctly in the sun. The cylindrical device measures the quality of the water, the temperature, the intensity of UV radiation, and calculates the time the bottle must be exposed to the sun’s rays. And the development team never lost sight of the needs of the people intended to use their invention. Maike Taddiken explains: “Easy-to-understand pictograms on the display show the user when the water is ready for drinking – no problem even for children and people who can’t read.”

Next invitation: iCAN in Alaska

Following this initial success the students have no intention of resting on their laurels. They have already received an invitation to participate in the international iCAN competition (Contest of Aplications in Nano-micro Technology) to be held in Alaska next June. In the meantime they will be looking for ways to improve further on their prototypes.

Photo of a group of five men and one woman
The prizewinning team (from left) Konstantin Tscherkaschin, David Horch, Theodor Hillebrand, Maike Taddiken and Yannik Auth.
Close up of a small device to messure the water quality
The components used in Scipio are very tiny. The cylindrical device had to be designed to fit through the neck of a bottle.