Clean water from solar energy
Researchers developed a fully independent solar reactor system for purifying drinking water in remote locations. Furthermore, the system did not require the addition of chemicals. Instead, solar energy was used to eliminate traces of organic contaminants from drinking water in rural households of the developing world. The SOLWATER team recognised the need for a robust and low cost system for measuring solar radiation in isolated rural areas. This challenge was met with the construction of two kinds of radiometers, which were based on cheap photovoltaic sensors. The devices measured the power of electromagnetic radiation including visible light. The radiometers' electronic systems used microcontrollers. These took the form of a computer system-on-a chip and contained a processor core, memory and programmable input/output peripherals. The microcontroller was used to calibrate each measured radiation with calibrated measurements appearing on an electronic liquid crystal display as W/m2. The autonomous radiometer system created by the SOLWATER researchers stored measurement data on its memory. The sampling time could be set for between 0.2 seconds and two hours and was capable of recording 4,000 state changes. Once long-term measurements were completed, the data was transferred to a computer using a serial RS-232 connection and suitably developed software. When the radiometer system was permanently connected to a personal computer, the data was transferred automatically and solar radiation plotted in real time.