RETO - DOSSO
The aim of the RETO-DOSSO research project is to contribute to sustainable livelihoods in the rural areas of Niger by creating essential basics and enabling rural entrepreneurial activities. To achieve this, the researchers use electricity from renewable sources to provide basic needs such as water and food. Surplus electricity from a decentralized solar energy system strengthens rural economies by generating simple, but creative business ideas as local sources of income.
The laboratory comprises three test stands: Hydrogen Renewable Energy Trainer (HRET), Fuel Cell Trainer (FCT) and Solar Hydrogen Trainer (SHT).
The HRET has various individual modules that can be interconnected. The large number of modules enables not only basic experiments, but also the investigation of real, operational problems such as
shading of PV systems. In addition to the energy source (230 V connection), the test objects in the form of photovoltaics (PV), wind turbine and a fuel cell can be investigated by means of measuring and control units as well as by means of safety devices. For fuel cell operation, there is an external hydrogen generator and two metal hydride storage tanks.
The FCT consists of a low-temperature fuel cell (PEM fuel cell, stack power 50 W) with a metal hydride storage (200 Nl). In addition, there is a variable electronic load, a load in the form of a traffic light, as well as a transformer to raise the output voltage of the fuel cell (4 V… 9.5 V) to 12 V. All measurement data are displayed directly on the FCT by means of analogue displays. The FCT can be connected to a computer. The corresponding software can be used to record measurement data. In addition, the experiments can be carried out with or without computer support.
The SHT is intended to explain the practical generation and application of solar energy. A functioning 230 V operating voltage is provided by two PV modules, 325 Wp each, connected in parallel, as well as an inverter or rectifier with integrated buffer storage, two 12 V lead acid batteries (60 Ah) connected in series. External devices such as the hydrogen generator (up to 72 l/h hydrogen) can be operated via the 230 V operating voltage. Thus, the SHT reflects the overall picture of a modern PV system, with the possibility of hydrogen production.
Decentralized energy system