1)Identify a sustainability problem
Contaminated water transmit water borne diseases such as diarrhoea, cholera, typhoid, and dysentery. Approximately, 502,000 people pass away from diarrhoeal death each year.
SODIS stands for Solar disinfection, and this technological approach is critical for developing countries that suffer from waterborne diseases.
2)Technology
The initial idea of using sunlight to disinfect water was already used in India a long time ago by putting water into trays under the sun. The fundamental concept of this approach is putting water in a transparent container and placing it under sunlight for 6 hours. When water is exposed to the solar UV light, it damages microbes and repairs endogenous microbial mechanisms.
The EU funds the technological development of SODIS technologies, and it aims to reduce childhood diarrhoea and dysentery in rural communities. The advanced technology harvest rainwater to meet water demand in deprived areas. In order to avoid contamination, the technology uses reactors that produce energy through solar panels. However, this simple water technology can be implemented at household level by reaching water temperature more than 45 celsius with the solar infrared light. The setback of the technology is that it takes a long time for disinfecting water to a satisfactory level. It also takes a lot more time under cloudy conditions. In order to overcome this setback, low-cost and simple water treatment techniques like solar concentrators/reflectors are implemented to increase radiation exposure.
https://cordis.europa.eu/article/id/415839-using-the-sun-for-water-disinfection-in-africa
3)Stakeholders
- People live in rural areas without access to treated water mostly in developing countries
- Multilateral organizations, many African organization that seek to solve water contamination
- Sub-Saharan African Countries such as Angola, Burkina Faso, Ethiopia, Ghana, and Kenya
4)Deploying the technology (household level)
- Provide sustainable containers such as polyethylene terephthalate (PET) bottles or clear plastic bags
- Place water and expose them to direct sunlight for 6 hours
- Individuals, households, small communities, and refugee camps use clean water by removing bacteria and virus
*While this simple technology is more applicable to many african countries, community level utilize the enhanced CPC photoreactor to dispense treated water into a collection tank.