SC 76: Excursion to the City of Chemnitz – A symbol of Renewable Energy Innovations and Energy Efficiency

By Enoch Bessah (Ghana)

The international short course of Renewable Energy Sources and Energy Efficiency [SC76], has been an exciting and insightful experience at CIPSEM for the 21 participants selected from 19 countries across five of the seven continents in the world. The first week was for familiarizing with the course content, Dresden, Germany and among participants. Through our various presentations (country report) and socialisation we shared about our culture and knowledge as well as resources for capacity building through one-on-one chats and lectures. After two weeks of lectures and field visits to German Environment Agency (UBA) at Dessau and German Biomass Research Centre (DBFZ) at Leipzig, it was an exciting moment to prepare early Monday morning to visit the Gold Municipality award winning city of Chemnitz. We were welcome at the City of Chemnitz Environment Agency by Dr. Thomas Scharbrodt, Head of the Environmental Authority in the city. As with other places we visited, the reception was “water, fruit drinks, coffee and tea” available on the table to energize us (keep us awake) throughout the presentations. I enjoyed this part of our excursion because it was an adaptation strategy to the weather by keeping the mouth busy and body warm.
The first presentation on energy transition in the City of Chemnitz was given by Ms. Carina Kühnel from their Environmental Authority. The energy and climate protection policy of the city is guided by three principles: environmental sustainability, social compatibility and economic efficiency and supply security. Chemnitz has a detailed integrated climate protection programme defined by the city council. Energy and climate change can be said to be intertwined. Solving the energy problem is addressing climate change according to my understanding of the climate protection programmes undertaken by the City of Chemnitz and the results achieved so far in their energy transition. The partners with various public and private institutions and organizations to implement defined programs. City of Chemnitz has exceeded the SEKo* 2020 target of 30% renewable electricity in the regional mix by 22% this year. The programmes of the city are worth emulating to tackle the global energy and climate problems at the municipal level.
The second presentation was on innovative heating solution at municipal kindergarten by Mr. Andreas Braumann. The concept of this innovation was to recover waste heat from data centre servers and use it at the municipal kindergarten in the City of Chemnitz. The first period of the implementation was 2011/2012, however, that of the kindergarten was on October 12, 2013. Recovered waste heat from servers is to be used in heating of buildings, domestic hot water and hot water systems. During the period of operation till November 15, 2013, the servers consumed 4.3 MWh of power and produced 10 MWh of heat. It is worth mentioning that useful heat from heating water during the same period was 2.85 MWh. Therefore, the waste recovery innovation from servers is the green way of increasing heat in buildings without direct consumption from electricity or other primary sources of energy. The Director of CIPSEM, Dr. Anna Goerner also made a presentation about solar construction work at FASA AG. Buildings are constructed with the architecture dimensions of solarthermal heating installations. This is another innovation to promote renewables in room heating. There are urban buildings with this design in the City of Chemnitz which we visited after the presentations.
IMG_6662After lunch, we visited three sites in the City of Chemnitz to see what was presented earlier at the Environment Agency. Our first stop was at the Solarthermal settlement developed by FASA AG. The solar systems are installed at an angle for maximum irradiation. Some of the buildings were still under construction which gave us an opportunity to see what is being done as presented in class. The completed solar residence (Solardomizil) and urban houses (Stadthäuser) were already occupied. This is an indication of the level of commitment of citizens to the energy transition plan. Although, Germany has not yet achieved national target in energy but there has been improvement towards the climate actions plan fulfilment. The second stop was at the battery storage system (eins) in the city of Chemnitz. The battery storage system has a rated capacity of 16 MWh. The response frequency of the battery system to changes on the grid is in split seconds. The battery in the system helps to prevent “blackout”, thus guaranteeing reliable power supply from the grid.  Our last site visit was to the municipal waste water treatment plant.
chThe plant incorporates energy efficiency in its operations as it recovers energy from the sludge through biogas generation. Waste water treatment is energy demanding. However, this plant has two of 36000 m3 tanks for biological treatment to generate biogas within 30 days. Electricity produced from the biogas generation covers two-thirds of the electricity demand in the facility. One thing that intrigued me at the waste water treatment plant was the information about the collection of rainwater from the city at the plant. This system although was not elaborated in the visit because it was not a focus, showed me, one practical and proven measure to mitigate urban flood in developing countries.

Our excursion to the city of Chemnitz enlightened us on energy transition at the municipal level which was aligned to the National energy targets and climate action plans. Our since appreciations goes to the CIPSEM team (lead on the trip: Dr. Anna Görner and Ms. Tamara Karp) for successfully organising this visit.