Developement of a measuring system for efficiency determination

From May to August 2020 the students Steffen Bißwanger, Leon Dungs, Sara Konrad, Nikola Milenkovski and Alexander Zinn  carried out a project as part of their studies at the TU Darmstadt in cooperation with our project SoWaDi. The goal was the development of a self-sufficient measurement system, which allows the determination of SoWaDi units efficiencies in the field. This is to be achieved by automated data collection of solar radiation, water output and environmental conditions.

In the following you can read some recordings from the students’ laboratory book. There they recorded their progress and described how they overcame the challenges they faced during the project.

Phase 1: Selection of components

09.04.2020 09:45

Today we firstly get to know each other, online of course, and get accustomed to the Solar Thermal Water Disinfection Unit we will work with during the project. Two of our team members already know the unit well. The rest of us are just getting to know it. In order to develop a suitable measuring system, it is important to have a good understanding of the function of the unit and the conditions in which it is used.

08.05.2020 15:15

Some time ago, we were able to agree on which quantities we wanted to measure. The important question now is: How? Today we discuss our latest ideas about which low-cost sensors and designs will give us the best results. A special challenge is to measure the amount of water coming out of the unit. In the past, several attempts have been made, which failed due to different reasons. Temperature variations from day to night have led to unreliable results of load cells and a sensor with moving parts blocked when it was used in wind and weather. But we have a new idea: a cut-off glass bottle with a small hole in the lid can be turned upside down to serve as a collecting container and accumulation device for the minutely water flushes from the unit. We then measure the time it takes for the glass bottle to empty again after a flush.

23.05.2020 17:18

We are finally ready: After 5 hours of discussion we have selected suitable components for all sensors, the computing units of the system, the data transmission and the power supply. Now all we can do is wait until the order arrives and hope that everything fits together.

31.05.2020 13:15

We just got the message that the first package has arrived. Now the real work can begin.

Phase 2: Programming and building the measuring system

31.05.2020 14:45

Except for one team member, none of us has worked with the microcontrollers we want to use for the project yet: Arduinos.

After we have set up the programming interface on the computer, we can finally load the first program onto the Arduino.

31.05.2020 14:46

The Arduino starts blinking. Hurray! Let’s see if it will be as easy to connect and read out the sensors as well.

02.06.2020 12:37

We were able to get the SD card reader, the current meters to measure the sun intensity and the simple thermometers working without any problems. The somewhat more complicated thermometers for the higher temperatures, however, only show strange values so far. Where they come from, we cannot explain. One thermometer shows us 65°C and another 9°C, both temperatures are definitely not correct.

02.06.2020 19:36

We just found a way to correct the strange values. One parameter in the calculation formula is a comparative voltage. While measuring this voltage at the sensors we noticed that it is different for each sensor individually. Now that we have incorporated this into the software, all thermometers show plausible values.

13.06.2020 09:42

We are now already in the middle of June, the weather offers optimal conditions to test the new measuring system. It is therefore about time to finally attach the measuring system to the unit. Therefore we are working at maximum effort to complete the circuit board for the measuring system. We solder all connections by hand. Hopefully our plan will work out. Also, the data transfer via the cellular module still doesn’t work. After we have ordered a better module in the meantime, at least we could get a connection to the mobile network, we unfortunately still haven’t managed to send the data automatically. Slowly time is running out. If we don’t manage to solve this, the whole project could fail.

14.06.2020 21:06

After two days of hard work the board is soldered. The measuring system can finally be installed in itscase, where it will be protected from rain when installed on the unit. We also made important progress with the sending of the data. The microcontrollers are now slowly reaching the limits of their computing capacity, further changes are becoming more and more difficult to implement. Fortunately, only a few minor software problems need to be fixed now, and then the measurements can start soon.

Phase 3: Attaching the measurement system to the unit

20.06.2020 09:16

The time has come: Today we can finally install the measuring system. It has been running continuously since yesterday and is ready for use.

20.06.2020 22:03

We have been waiting for the first data to arrive for 3 minutes now. Now comes the moment of truth. If everything goes smoothly today, we are confident that the measurement system will continue to work for the next three months until too little light is available in October.

20.06.2020 22:04

The first data have reached us. We are relived. We have done it and deserve a break for a while. As soon as we have enough data, we can start evaluating it and start to write a full report.


With the measurements over a period of 30 days, the team has succeeded in finding out which sensors are relevant and suitable for the assesment of efficiency. So that in the future it will be possible to build a low-cost measurement system that can perform all important measurements. Almost the entire team will continue to develop the measurement system on a voluntary basis at Engineers Without Borders in Darmstadt. The new measurement system is called MONA (Monitoring Offgrid Node for Assessment of SoWaDi Performance). In the future MONA will help to collect long-term data in Tanzania and to further develop the SoWaDi unit in Darmstadt. In contrast to her mother, MONA is a little smaller and more compact, and also not as transparent, just perfectly equipped for a world tour.

Video of our presentation “Introduction to SoWaDi”

Hello everybody!

As already announced in the previous blog entry, we had the possibility to give an online talk for SoWaDi supporters on 29.10.2020.

The presentation, which we are now able to provide in form of a video, gives an overview of the idea and the history of our research project, as well as of our project phase in Tanzania in spring 2020 and an outlook into the future. It was held by three members of the project group: Julius Breuer, Sara Konrad and Jan Erik Schliephake. Philipp Erdmann from the Darmstadt regional group was the moderator.

We apologize that the presentation is only available in German. Nevertheless, we would like to make it available here as well. The talk lasts about 30 minutes. Afterwards you can listen to the entire Q&A session of about 20 minutes. Unfortunately, the first 20 seconds of the presentation are missing due to technical difficulties. This is a great pity, but does not diminish the content of the lecture in any way! 🙂

We would like to thank all those who took part and made for an exciting Q&A session with their questions!

If you have any further questions about the lecture or the project, please contact us here:

[1] Icons made by Good Ware from
[2] Icons made by srip from
[3] Icons made by Freepik from
[4] Icons made by Icongeek26 from

Invitation to our SoWaDi online event

Access to safe water has been recognized worldwide as a human right since 2010. However, contaminated water continues to be a major problem for the health of the local population in many parts of the world. Therefore we develop SoWaDi.

SoWaDi stands for Solar Water Disinfection: The solar water disinfection systems developed and researched in the project use solar energy to improve the water quality. Since 2010 we have been developing technical solutions together with local partners in rural areas of Tanzania to improve the water situation for families and at schools.

The aim of our project is to ensure that as many people as possible have access to germ-free water, because clean water protects against diseases such as typhoid fever and cholera. To achieve this, a construction manual is available free of charge. This enables everyone to build and install the system themselves using locally available, inexpensive materials.

The work, which continues despite the corona pandemic, is carried out in close cooperation with our local project partner Kilimanjaro Childlight Foundation (KCF). In Tanzania, together with local school groups and families, six of the systems have already been installed. The local supervisors of the facilities regularly collect and evaluate the data, which is then used to continuously optimize the facilities. In this way, we want to identify possible weaknesses, improve effectiveness and contribute to a long-term and sustainable solution for rural water supply. In July, a team from KCF was able to visit the plants and ensure that they were back in operation in time for the beginning of the dry season.

If you would like to know more about how our solar water disinfection system works, how we continue the research and development work together with KCF in Tanzania despite Corona, or if you have any further questions, please take part in our online event in German language “SoWaDi introduces itself: Solar energy for clean water” on Thursday, 29.10. at 19:00! To get the link to the event, please write an E-Mail to:

A small update from Tanzania

Hello everybody! 

We have some exciting news from Tanzania that we would like to share with you. Our devices TZ03, TZ04, TZ05 and TZ06 are now nine months old, so it is time for a water test to ensure that the quality of the output water is still good. Unfortunately, only TZ03 and TZ04 have been tested so far. The other devices were covered when the test was carried out. Please make sure to follow this blog, we will definitely post the other results as well.

The results from TZ03 and TZ04 look very promising! Both devices use input water which is heavily contaminated with E. coli bacteria. After the treatment, no bacteria were found in the devices’ output water. This result was validated by the laboratory MUWSA (Moshi Urban Water Supply And Sanitation Authority). It means, that water treated by both devices is safe for everyday use. We are motivated by those results as they show us one more time that the SoWaDi-concept of treating water works, even over longer periods of time. The exact test results are posted in the picture-gallery above. If you have any questions regarding the testing, do not hesitate to contact us using the contact-sheet… 😉 

Besides the negative test results, all devices are in a good shape! Minor repair jobs like changing the containers’ tap or cover were done, but all in all the devices mastered the rainy season with no problems.

Here you can see the output of TZ04. The blue bars represent the daily output, the average output is 6 liters per day.

Right now, the devices’ output is relatively low (an overview of the output from TZ04 is displayed in the picture-gallery above). Hopefully, the weather will get a little better, so we can see an increase in output. Let’s keep the fingers crossed! 

Stay safe and healthy! 

Long awaited presence meeting of the project group

Hello everyone, 

Steffens explains the progress they have made within the Advanced Design Project.

After now more than three months since the project meetings have been switched to a virtual way, a long awaited meeting took place again on Friday the 17.07. All SoWaDi members who had time and were in the mood spent a very nice evening on the area of the device. The meeting was decoupled from the actual project meetings and should mainly serve to strengthen the group.

Group photo.

Also present were Steffen and Alex, who together with Sara made our devicethe center of their ADP (Advanced Design Project). In the past semester they have been working intensively on the question of which long-term data are usefuland how to optimize the measurement technology. On Friday they shared their work progress and findings with the entire group. It was very interesting and the three have done a great job in the last months! A separate blog entry on the details of their work is already being planned. 

The coming together was very nice. Until the evening hours we had a picnic together and talked about all kinds of things. However, despite all the joy of the reunion, we also always made sure to wear masks and keep a safe distance. Even though the situation in Germany allows for more face-to-face meetings, we decided to continue to work together virtually. So far the regular meetings have worked well that way  and each group continues to work very hard on its self-chosen work packages.  

While we hope to meet again soon in person, we recognize the urgency to avoid accumulations in order to protect ourselves and our loved ones as much as possible! 

Stay healthy and look forward to an early update from the ADP team!  

Hello everybody!

Visitation of the facility TZ01 at Malage VTC. 

During the last weeks we have received news about our devices from Tanzania and so we take the opportunity to share this news with all interested parties in the following blog entry.

KCF-Team und users at TZ01. 
Visitation of facility TZ02 at Malage VTC. 

The Kilimanjaro Childlight Foundation travelled with a small group to Malage VTC and Kidia to visit the six facilities and exchange information with the users. It turned out that currently only three of the six built devices are in operation. Due to the COVID-19 pandemic and the resulting school closures, the facilities of Kidia Primary and Secondary School are still not in operation, but this is expected to change with schools opening soon.

Those Employees of the Kilimanjaro Childlight Foundation have visited our facilities.

In addition, the weather in Tanzania is still very cloudy , as the rainy season has only recently ended. Therefore, the planned extraction of water samples could not take place, because the devices unfortunately do not provide any output without sunshine. For the same reason another device is still covered, but this one will be active again as soon as the weather allows it. 

At the Malage VTC the devices are running as planned, which makes us very happy! 

We hope that all SoWaDi participants are doing well according to the circumstances and we are looking forward to further feedback from Tanzania as soon as the devices are up and running again. 

Stay safe and healthy! 

TZ04 in Kidia.
KCF-Team and users of TZ04 in Kidia.

Despite the lockdown: the work continues

Hello everyone!  

Our departing people are back in Germany for a month now. During this time a lot has happened and we would like to give you a small update about our current work as well as the situation in Tanzania and in Darmstadt with this blog entry.  

Our current work:

Recommissioning of our first test unit on the Lichtwiese in Darmstadt.

Immediately after the return of Rebecca, Jonas and Julius from Tanzania, the follow-up of the departure started. This includes not only the viewing of pictures, notes, etc., but also constant communication with our project partner, the Kilimanjaro Childlight Foundation (KCF), and the users of the units. Furthermore, the costs of the individual units are estimated and the interviews with the people on site are evaluated. 

We have established a support group that maintains contact with Tanzania to collect feedback and the recording of the weekly sent measurement data to maintain contact with Tanzania. The measurement data collected in this way includes the daily water output of the 6 plants as well as information on the weather. These weather data can be compared with the data of an online database in the future and allow a more detailed analysis of the output data. 

During the departure, minor design changes were also made to the unit, which are now being discussed in the Performance Issues Theme Group and included in the assembly instructions by the Instruction Group. Our goal is to include major design changes in the planned setup of the second test unit here in Darmstadt. 

A special focus is currently on measurement technology. Within the scope of an Advanced Design Project (ADP), 5 students are working on a robust, inexpensive and easy-to-implement measurement electronics, which will be installed in our second test unit in summer. At the same time, scales for characterizing the performance of the system are to be determined. The ADP tendered for this purpose is supervised by the Institute for Technical Thermodynamics at the TU Darmstadt. 

Effects of the COVID 19 pandemic on our work:

The water is drained off at the covered TZ01 unit at Malage VTC.

Of course, the COVID 19 pandemic has a major impact on our work. In this blog entry we would like to give you a short insight into the situation in Tanzania. For this purpose, we have received insights into the current life in Tanzania from Ichikael, our contact person at KCF, and Gasiano, the headmaster of the Malage Vocational Training Center, where the departure team has put the two units of 2017 back into operation this year, which we would like to present to you here briefly.

Ichikael (Communication on the 1st of april):  

Ichikael has a son and also takes care of her nephew. Both of them have to stay at home right now because the schools in Tanzania are closed. She takes over the work of the teachers – unfortunately, the two little ones want to go back to school despite all her efforts. Currently the question arises whether the exams should also be written at home.  

Other facilities such as markets and churches are still open, but mass events have been cancelled. People who do not take the situation seriously are particularly problematic. Many do not particularly restrict their public life, hygienic protective measures, such as washing their hands, are often not taken. 

Although comparatively few people are in quarantine in Tanzania, the tension is still noticeable. The infection figures from Europe are being followed with great concern. 

Gasiano (Communication on the 25th of march):  

The TZ03 unit at Kidia Primary School is also covered.

Gasiano describes the current situation as difficult. It is a pity that his school is closed to students; neverless he sees the situation positvely because of the still low infection figures. The teachers at his school continue to carry out their duties, such as maintaining the school or cultivating the school gardens. The government’s school closures are expected to continue until 17 April and will be closely monitored. If a school opens despite the governments‘ orders, the headmaster risks a permanent closure of the institution.  

Gasiano has five children. His daughter is studying in Xi’an, China and came back to Tanzania in February because of COVID-19. The family is happy that she is at home and everyone is healthy. Through various news channels they are informed about the situation in other countries. Especially the situation in Italy is followed with great concern.  

We are very happy that all users and contributors in Tanzania are doing well according to the circumstances. Although public life is partly restricted, this is the only way to slow down the spread of the virus. The constant contact with the users on site is especially important in these times!  

As some of our units are located on school grounds, some of them have been put into standby mode. For this purpose, the absorber box is covered with a plastic sheet that is impervious to light so that no components are heated by the sun. At the moment three of the plants are in this state. The remaining systems are still in use and measurement data is sent to the support group on a weekly basis.  

Of course, the way of working within the project group has also changed over the last few weeks. Since everyone works in his home office, alternatives for meetings and project group meetings had to be found. For our meetings every second Tuesday we use a program for voice conferences. There is a lot of communication via social media and lectures can be presented via a special website.  

In spite of all the technical helpers, we are looking forward to hours together again reunited in the university group house!  

Stay healthy and until then:  

Kukaa na afya na mpaka wakati huo!  

Behind the Scenes – A Report from the Back Office

Of course the project group did not stop to meet in Germany during the time, Jonas, Julias, Rebecca and Edgar were abroad. Besides back office tasks, we also continued with project work.
That’s me, Sara Konrad.

Hello, I’m Sara Konrad. At the end of this year’s journey, I’ll share a different perspective from the back office. The back office has actively supported the outgoers from a distance, but has also maintained the normal project operations in Darmstadt. 

I am 25 years old and am studying Mechanical Engineering and Energy Science and Engineering. Already since 2015 I have been working for Ingenieure ohne Grenzen in Darmstadt, but I started working for SoWaDi only two years later.

For a long time I was exclusively involved in the organisational work of the whole regional group, wrote newsletters, organised teambuilding events and coordinated the working media of the regional group. It was personally important to me to be involved in development cooperation. However, after two years, during which I was purely involved in organisational work, I wanted to get into a project and decided to join SoWaDi. Especially in the project SoWaDi it is very well possible to enable many people to have a better life situation by improving the water supply.  In SoWaDi I had the feeling to be able to use my knowledge from my studies in the best possible way.

At the beginning of my project work the outgoing team of 2017 had already been back from Tanzania for a few months and the phase of follow-up work was in full swing, so that plant optimisations resulting from the journey were tackled. The trip to Tanzania had shown that the plant could be optimized at some points in order to contribute to higher efficiency and robustness and to simplify the distribution. My task was to deal with the glass breakages that occurred in Tanzania. One of the results was that the highly stressed lower glass pane was divided into several small glass sheets. 

Besides technical challenges of SoWaDi it was not possible for a long time to find a location for a test plant in Germany which would have allowed us to have the plant in operation for more than six weeks. Therefore I was very happy that we finally found a location in early 2019 and a few months later we could build a plant at the TU Darmstadt which will be there for at least 3 years. This enables us to test changes in practice and collect long-term data.  

Besides the skills I have acquired through the engineering work, I have learned a lot about working together and efficiently in large groups. Since October 2018 I have been the contact person of SoWaDi and have learned a lot about successful group management and organisation and was able to use the already acquired skills from my IOG beginning time. 

Furthermore, this work has made me much more sensitive when it comes to intercultural communication and development cooperation. Also the attendance of some seminars for further education of Engineers without Borders has contributed to this. Through this work I have gained a completely different perspective on topics such as everyday discrimination and racism. 

While the outgoing team was working in Tanzania, it was my job to support them as much as possible and to derive tasks that the back office can take over for them. This way they could concentrate fully on their tasks on site, while I always knew what was coming up for them and was involved in the important decisions. 

The activities of our back office team were mainly of an organizational nature: we wrote the blog entries and donation reports, answered questions from the outbound team and in doing so, promoted the long-term orientation of the project. 

All six SoWaDi plants have a unique serial number. Obviously, a type plate should not be missing.
From the users of the plants we regularly receive data about the plants. This allows us to see how the performance changes over time.

In addition, we had enough time during to bring in the communication between us as SoWaDi team in Darmstadt and the users of the facilities. The nice thing about it was to see that not only we could give input to the people on site, but also the dedicated users gave us suggestions for improvement of our work, so that we are already a well-rehearsed team with most of the users. This was a very important sign, which reflects the good course of the departure and hopefully is an example of how things will go when the outgoing team is back in Darmstadt. 

I am also particularly pleased that the project will continue in Germany. The test phase is also entering the next round here in Germany: In cooperation with the Institute for Technical Thermodynamics at the TU Darmstadt, we want to further optimize our measurement technology concept to increase the efficiency of the system. A twin is to join the plant, which is already here in Darmstadt, at the beginning of summer. The idea is that the improvements we will be making to the twin plant will not only be implemented even faster, but above all we will be able to evaluate them directly in comparison with the standard plant. 

Last week, the departure team had important meetings with the project partner, which had to be conducted directly with the responsible persons on site.  These meetings were extremely important, so that the Kilimanjaro Childlight Foundation can be the interface between us and the users in the future, should there be any problems with the installations or with the communication among each other.

On Wednesday 04.03.2020 Jonas, Julius and Rebecca started their journey home with a heavy heart and arrived safely in Germany on Thursday morning.

Now that they have left the country, the first thing to do is to do some follow-up work so that no valuable knowledge is lost.  There have been a lot of exciting discussions on the subject of the distribution of the plant and we have to continuously process the data we constantly receive from the users. 

When the immediate follow-up is complete, the biggest challenge for the team will be to crystallize the other essential project tasks and to focus on the newly set goals. These will certainly include, among other things, the technical challenges that arose during the construction of the six plants, which the outgoing team will report on in detail in the coming weeks. 

All in all, I am extremely pleased that the departure went well despite some minor challenges. We can be really satisfied and proud, the long preparation was worth it. An extraordinary amount was achieved, not only by the outgoing team and by us in the back office, but also by the people on site, most of whom we did not even know before leaving. The fact that the feedback from working together on site was always positive was a welcome reward for the last months of intensive preparation. 

We realize how important it is to continue working on our project. Not only because we ourselves are fascinated by it, but also because the local people see the necessity of the plants and their advantages over existing methods of water treatment. The problem of the water situation is and will continue to be topical in many regions of the world and for all these people it is worthwhile to further revise the plant and to optimise dissemination strategies so that as many people as possible can benefit from it.  

Well prepared for the test phase

A collective meeting: Together with the other project participants, I am delighted about the successful conclusion of the past weeks.
This is me, Samwel Masaga. 

Hello, my name is Samwel Emmanuel Masaga and in this blog I will tell you about the current state of the SoWaDi project and my role in it. First some things about me: I am 25 years old, live in Moshi, studied Wildlife Management at the Sokoine University of Agriculture and work as Project Manager at KCF (Kilimanjaro Childlight Foundation). In this function I have only been working on the project since February and had great respect for getting into the subject. However, with the help of Rebecca, Jonas, Julius and Edgar, it was made very easy for me to get started, so I now feel in good hands with the project. I like the fact that I always have the chance to learn something different, to have new, intensive encounters with different communities and thus broaden my horizon.  Above all, I find it remarkable that the project aims to improve the water situation in our communities.  

In the Secondary School Rebecca gives our workshop on water and hygiene. The pupils work on the different ways of transmission of diseases.

When I was little, we sometimes boiled the water on a fire, but that always involved a lot of work. Before that, firewood has to be collected and brought home. This sometimes involved long journeys and after the working day my parents were usually too tired for that. Drinking it from the tap is much more comfortable. But here in the region it is mostly coupled with health risks. I am convinced that SoWaDi can make a big difference here.  

After the last SoWaDi plant has been installed, information flyers and other material are handed out. In the future, interested visitors of the family can learn more about the plant.

When I was not allocated to the project that long yet, I had the chance to watch the completion of the first plant in Kidia, the second location, together with Jonas and Rebecca. I was very impressed to see the hot water and some steam leaving the plant. Treating water with the sun is a rather unknown technology and many, including myself, find it difficult to understand directly what exactly happens. After seeing the plant in action for the first time, I had no doubt that the water is actually boiled.  

To give you an impression of the last week and my work at SoWaDi I would like to tell you a little bit about it:  

Ichikael and Rebecca meet Mr. Machunda from the African Institute of Science and Technology. He is an expert in the field of materials science.

At the beginning of the week, the construction team, together with Jonas, Julius and Rebecca, completed the sixth and last plant of this trip. Julius and Rebecca held a workshop on water and hygiene at the secondary school in Kidia. During the almost two hours, interesting questions of the about 60 students about different aspects of water and especially about its treatment arose. 

Later in the week, Jonas and Julius went on to the Malage VTC. There they worked on the last open points and took water samples of the first two plants again to make sure that they continue to deliver safe water. Meanwhile, Rebecca and Ichikael travelled to Arusha to meet with Dr. Hilonga from Nanofilter and Dr. Machunda from the Nelson Mandela African institute of Science and Technology. Primarily topics concerning the possible future expansion of the plant were discussed, but contacts were also made to further benefit from each other and to exchange knowledge. 

The head of the laboratory of the local water authority explains to us what is important when taking water samples. Afterwards we practice taking samples.

On Friday I learned how to take water samples together with Rebecca and my KCF colleagues Samier and Ichikael. We were professionally trained by our contact person at MUWSA, the local water authority in Moshi.  

The Kidia construction team proudly presents what we have achieved together. 

The functionality of the plant should be checked at regular intervals during the test phase. For this purpose, it is necessary that water samples of the untreated input water and the safe output water are taken to a laboratory and examined there. My colleagues and I take over the task of taking the samples from the plants and handing them over to the laboratory. Here we have to pay special attention to the fact that mistakes during sampling can lead to incorrect results. I was able to learn all this and much more during the training. I am pleased to be able to actively shape the test phase with this newly acquired knowledge. 

Julius and Mr. Abed next to one of the first plants in Tanzania. At the Malage VTC, they tackle open points together. 
At the meeting on Sunday a lively exchange about the experiences with SoWaDi plants takes place.

At the end of this successful week, we all drove to the Secondary School in Kidia on Sunday to do a “get together” with all users of all the facilities. The aim was for everyone to get to know each other and to be able to support each other in the future if necessary. As a contact person of the KCF I also play an important role in this, especially when Jonas, Julius and Rebecca are back in Germany. We took the opportunity to visit the plant there together, and there was a lively exchange on the similarities and differences between the respective plants.  

Afterwards the plant at the Kidia Secondary School is visited and differences between the plants are discussed.

So far, we have built six plants together at three different locations here in the Kilimanjaro region of Tanzania and have already been able to help some people to get access to safe water. This is what I really wish for: That this project does not just take place in a few spots, but becomes big. It should spread further, not just in one or two places, but throughout Tanzania and beyond. I am sure that there is a demand for SoWaDi plants, which are easy to operate and maintain, in many places in Tanzania. Above all they are an alternative way to get germ-free water without time-consuming wood collecting and without laborious wood fires. I think that currently especially smaller schools and orphanages can benefit enormously from this technology, because the daily output of the plant is still too little for larger facilities. Because it was very easy for me to understand the plant and to get familiar with the project, I am sure that there are always people who are also enthusiastic about SoWaDi. These people will then be willing to take over the task of operation and maintenance and thus contribute to an improvement of the living situation in their environment.

Together – two projects, one region

On Monday I discussed with the teachers of Kidia Primary School what is important for the trouble free operation of the plants.
T his is me, Julius Breuer.

Hello, my name is Julius Breuer, I am 26 years old and I have lived in Darmstadt now for 6 years. There I study Master of Mechanical and Computational Engineering at the Technical University. I rather coincidentally found my way to “Engineers without Borders” via a project of the university and joined the project SoWaDi with enthusiasm: In contrast to my studies, I was able to deal with technical questions in a very practical way. I was able to share this motivation with many others. Together we have learned to approach emerging problems. In the process friendships have developed which I would not want to miss anymore.  

At Maki Secondary School, a teacher and I measure the steepness of the school grounds. For this we use a hose scale. 
Then we measure the height of the building. This is interesting for the location of the rainwater cistern.

In the beginning I took over the evaluation of measurement data at SoWaDi. In order to further improve the evaluation, we decided to build a test facility with measuring instruments. This way we would like to learn how to further optimize the plant. Today it is located at the Lichtwiese in Darmstadt. Since the conditions here are not the same as those where the systems will serve their purpose in the future, this is also a major goal of our current departure: We would like to equip further solar water disinfection plants with measuring instruments for data acquisition on site, in order to create a basis on which we can build in the future.  

The fundament for the Kidia Secondary School is being aligned.
To bend the sheets, the builders use a self-made tool. 
Together students, teachers, our construction team and Jonas bend the copper pipe for the fifth plant.
Step by step the absorber is completed.
During an event on Sunday I explained our plant to interested people from the community.
Meanwhile Jonas and Rebecca present our project in the church of Kidia. 

When planning our departure to Tanzania, a problem became apparent: Unfortunately, we were not able to make good use of the experiences gained during our visit in 2017 and build on them. With the fluctuation of those involved at that time, a lot of knowledge was also lost. We are therefore developing various strategies for knowledge management. One of the tools we are using is a kind of project wiki. But personal contact should not be underestimated when passing on knowledge. So it was also our good luck that Kasimir told us in detail about his experiences, the country and the culture before leaving and answered our questions. In the end, this also increased our anticipation of a journey that would bring new experiences, impressions and perspectives.

We are now at the end of our journey. If we want to stick to our goals, there should be no problems that cost us time, because there are only 10 days left. Although we have almost finished the construction, we still want to connect the different plant supervisors* so that they can support each other and develop a network that ensures the maintenance of the plants on site. We also want to strengthen the contact from Germany and thus contribute to the long-term preservation of the project. In this respect the week was very successful. Like the others last time, I would like to tell you about our last week in the following: 

On Monday we were able to start the week successfully with a user training for the fourth plant.  On Tuesday, Sam from KCF and I set off for Rombo, while Edgar enjoyed his last full day in Moshi before leaving for Germany on Wednesday. In the Rombo region, Sam and I visited the Mamtukuna Folk Development College, which could become a future project partner, as they have all relevant aspects for the construction of the plant. However, there is a lot of rebuilding going on there at the moment, so the location was not yet available for the current departure. Afterwards I met a contact person of a project of the Regional Group (RG) Cologne in Mashati. We had got to know the project of the RG Cologne in advance during an association-wide exchange of experience on the topic of “water, sanitation and hygiene” and found out that we are active in the same project region. Their project is the construction of a large rainwater cistern at a school. This is to improve the water situation at Maki Secondary School. Also the RG Köln was missing important data. Therefore, we interviewed a stone supplier, visited a reference project and surveyed the area for the new facility in terms of building heights and gradients. We also benefit from the cooperation in the region: Through them, we have found our partner organisation KCF and are able to take on smaller tasks for each other before leaving the region.   

On Thursday I drove back to Kidia, where Rebecca, Jonas and I worked with the construction team on the penultimate plant. They had been working on it since Monday and for the first time during this trip they bent the sheets for the absorber themselves. This worked very well with the help of a self-made sheet metal bending device built according to the operating instructions. But there was no time to take a rest, so after the completion of the fifth plant we immediately brought all the necessary materials to the sixth location, in order to start building the last plant on Monday.  

The week ended on Sunday in Kidia in the church. There we were invited to the church service and could present our project to the church community afterwards. We talked about the relevance of safe water. Afterwards we were able to answer the invitation and invite those present to visit one of the plants and ask further questions.   

Looking back on the week, I ask myself more and more: How can we ensure that the newly built solar water disinfection plants function as long as possible, that knowledge about their construction, use and maintenance is preserved and disseminated? The sustainability of our work is of particular concern to me, and the experience I have gained allows me to reflect more critically on development cooperation than before. I must also always keep a critical eye on my own actions. Cooperation is often not as easy as I thought in advance and we have to improvise a lot in order to achieve common goals. Before we left, for example, I didn’t expect language to be as big a barrier as it actually is, since many of our project partners* here hardly speak any English and I don’t speak Swahili.   

I am curious about the next few days and excitedly await the test phase of the six plants that have been erected. Many greetings from Kidia, yours, Julius.