How To Use Solar Disinfection: 

Step 1

Fill a plastic bottle with source water.

Step 2

Leave the bottle in direct sunlight for six hours. If it's a cloudy day, leave the bottle out for two days instead.

Step 3

Drink the disinfected water straight from the bottle!

In SODIS, a combination of UV light and heat from the sun destroys disease-causing bacteria, viruses, and parasites.

Why is SODIS special?

SODIS has many advantages that lend it for use in impoverished areas and developing countries, including:

  • Proven reduction in pathogens: up to 99.9999% reduction of some bacteria
  • Low cost of implementation: less than $1 per person per year
  • Ease of use: used by over 5 million people every year
  • No taste change

 

The efficacy and capability of SODIS has been consistently shown in research studies around the world. Current published data on SODIS clearly supports its advantages in several countries, such as:

  • India
  • Cambodia
  • Kenya
  • Uganda
  • Bangladesh
  • Peru
  • Cameroon
  • Costa Rica
  • Ethiopia

This map summarizes the current published research on solar water disinfection and its effectiveness in reducing bacterial loads in contaminated water sources. Each point on the map includes important data and information from a SODIS study. The gold star icons indicate the specific research studies that reveal an especially important fact about SODIS.

Do people use solar disinfection?

 

Over 5 million people in 28 developing countries around the world use SODIS for the treatment of regular drinking water. SODIS has been explored since the 1980's and is a proven method for making water safer to drink.

Figure 1: SODIS Use in 55 countries around the world (McGuigan et al, 2015)

Great! What's the catch?

The simplicity of SODIS does present some challenges to be overcome: water that is too cloudy must be pre-filtered, limited quantities can be purified in each batch, and most importantly, it is hard to tell when the water is actually safe to drink!

Because cloud cover, differences in bottles, and water cloudiness impact purification time, one set of simple guidelines can't address the needs of the diverse communities around the world who could benefit from using SODIS. Learn how the OSPRI solves these problems

Solar Disinfection has great potential, but there is still room for improvement.

Learn how the BBP-designed OSPRI is enhancing SODIS to make it easier, faster, and more accessible.

References:

Altherr AM, Mosler HJ, Tobias R, Butera F. Attitudinal and relational factors predicting the use of solar water disinfection: a field study in Nicaragua. Health Educ Behav. 2008;35(2):207-20.
Andra SS, Makris KC, Shine JP. Frequency of use controls chemical leaching from drinking-water containers subject to disinfection. Water Res. 2011;45(20):6677-87.
Aziz F, Mandi L, Boussaid A, Boraam F, Ouazzani N. Quality and disinfection trials of consumption water in storage reservoirs for rural area in the Marrakech region (Assif El Mal). J Water Health. 2013;11(1):146-60.
Caslake LF, Connolly DJ, Menon V, Duncanson CM, Rojas R, Tavakoli J. Disinfection of contaminated water by using solar irradiation. Appl Environ Microbiol. 2004;70(2):1145-50.
Christen A, Duran pacheco G, Hattendorf J, et al. Factors associated with compliance among users of solar water disinfection in rural Bolivia. BMC Public Health. 2011;11:210.
Conroy RM, Meegan ME, Joyce T, Mcguigan K, Barnes J. Solar disinfection of drinking water protects against cholera in children under 6 years of age. Arch Dis Child. 2001;85(4):293-5.
Dessie A, Alemayehu E, Mekonen S, Legesse W, Kloos H, Ambelu A. Solar disinfection: an approach for low-cost household water treatment technology in Southwestern Ethiopia. J Environ Health Sci Eng. 2014;12(1):25.
Graf J, Zebaze togouet S, Kemka N, Niyitegeka D, Meierhofer R, Gangoue pieboji J. Health gains from solar water disinfection (SODIS): evaluation of a water quality intervention in Yaoundé, Cameroon. J Water Health. 2010;8(4):779-96.
Halperin M, Paz-soldán VA, Quispe V, Paxton A, Gilman RH. Sustainability of solar disinfection to provide safe drinking water in rural Peru. Public Health Rep. 2011;126(5):762-8.
Islam MA, Azad AK, Akber MA, Rahman M, Sadhu I. Effectiveness of solar disinfection (SODIS) in rural coastal Bangladesh. J Water Health. 2015;13(4):1113-22.
Mcguigan KG, Conroy RM, Mosler HJ, Du preez M, Ubomba-jaswa E, Fernandez-ibañez P. Solar water disinfection (SODIS): a review from bench-top to roof-top. J Hazard Mater. 2012;235-236:29-46.
Mcguigan KG, Samaiyar P, Du preez M, Conroy RM. High compliance randomized controlled field trial of solar disinfection of drinking water and its impact on childhood diarrhea in rural Cambodia. Environ Sci Technol. 2011;45(18):7862-7.
Mustafa A, Scholz M, Khan S, Ghaffar A. Application of solar disinfection for treatment of contaminated public water supply in a developing country: field observations. J Water Health. 2013;11(1):135-45.
Okurut K, Wozei E, Kulabako R, Nabasirye L, Kinobe J. Calibrating an optimal condition model for solar water disinfection in peri-urban household water treatment in Kampala, Uganda. J Water Health. 2013;11(1):98-109.
Rai B, Pal R, Kar S, Tsering DC. Solar disinfection improves drinking water quality to prevent diarrhea in under-five children in sikkim, India. J Glob Infect Dis. 2010;2(3):221-5.
Rainey RC, Harding AK. Acceptability of solar disinfection of drinking water treatment in Kathmandu Valley, Nepal. Int J Environ Health Res. 2005;15(5):361-72.
Rose A, Roy S, Abraham V, et al. Solar disinfection of water for diarrhoeal prevention in southern India. Arch Dis Child. 2006;91(2):139-41.
Tedeschi CM, Barsi C, Peterson SE, Carey KM. A pilot study of solar water disinfection in the wilderness setting. Wilderness Environ Med. 2014;25(3):340-5.