Imagine an end to boiling your water in order to make it safe. Consider how nice it would be to no longer need expensive water filtration devices or potentially toxic water-treatment chemicals. Sounds great, right? Too good to be true, even…

In reality, solar water disinfection (SODIS) really is a good fit for equatorial countries with abundant strong sunlight and few other resources. This water treatment method simply uses the sun’s energy for disinfection. The most common technique is to expose plastic bottles full of contaminated water to the sun for a minimum of one day. The sun’s abundant UV light kills or damages almost all biological hazards in the water. The advantages to this way of treating water are plentiful. It’s easy; it’s inexpensive or free; it offers good (but not complete or guaranteed) bacterial and viral disinfection. Furthermore, the method uses no dangerous chemicals and it does not require constant attention.