Solar and SODIS: Creating Clean Water for the World
Students will be introduced to the range of microbes in the environment, understand the risks of “dirty water” and be able to explain how energy from the sun can purify water through the SODIS technique.
According to Nobel Laureate Richard Smalley, the number one and two challenges for humanity are energy and clean water. This classroom activity will introduce students to a low cost, renewable technique that connects these two issues. During the activity, students will learn about the risks of contaminated water as part of the spring microbe/microscope unit. They will then be introduced to the SODIS technique (solar UV water disinfection) and learn about the different energy sources in sunlight and how they can be used to kill microbes in water. Students practice the scientific method as they choose which two variables they would like to test (bottle vs. plastic bag, reflective surface vs. black tarp, wind cover vs. exposed, angled roof vs. ground, etc.), create a hypothesis on how these variables will affect coliform levels in the water sample (collected from the Willamette River in our case), collect data on agar plates and then share their findings with the class.
