Sun in the Oven
by Karyn Ellis
Tuesday, June 23, 2009
Across Africa, cooking fires are projected to release about seven billion tons of carbon in the form of greenhouse gases by 2050. More than 1.6 million people, primarily women and children, die prematurely each year from respiratory diseases caused by the pollution from such fires. Scientists estimate that smoke from wood cooking fires will cause 10 million premature deaths among women and children by 2030 in Africa alone. These statistics can be addressed by promoting inexpensive, effective solar cookers, along with hay baskets (retained-heat devices that extend cooking temperatures after food is removed from a heat source) and fuel-efficient stoves for cooking when sunshine isn't available. These technologies are made with local materials whenever possible, and are easily used and constructed by anyone willing to learn.
Smokeless cookers can dramatically reduce respiratory infections caused by smoky fires, treat drinking water by eliminating waterborne pathogens, reduce the debilitating effects of deforestation, free time from hours of firewood gathering for women and girls and enable young girls to attend school rather than spend their days looking for firewood.
Millions of people become sick each year from drinking contaminated water. Worldwide, about 1.3 billion people do not have access to safe drinking water, resulting in an estimated 1.5 billion cases of diarrhoea each year and the deaths of nearly two million children. Yet, in many of the most severely affected regions, sunshine is an abundant source of energy that can not only cook food but can also heat water to temperatures that kill harmful microbes, making water safe to drink. This process is called solar water pasteurisation.
SCI co-founder Dr Bob Metcalf, a Professor of Biological Sciences at California State University, Sacramento, studied solar water pasteurisation in the early 1980s with one of his graduate students. They found that water heated to 65�C for a short time will be free from microbes including E. coli, Rotaviruses, Giardia and the Hepatitis A virus.
Since thermometers are not accessible to many people around the world, there is a need for a simple device that indicates when water has reached pasteurisation temperatures. In 1988, Fred Barrett of the United States Department of Agriculture came up with the idea of using wax with a specific melting point as an indicator. In 1992, engineering student Dale Andreatta created the Water Pasteurisation Indicator (WAPI), a reusable clear plastic tube partially filled with a wax that melts at 65�C. So, with minimal investment in a simple solar cooker and reusable WAPI, people in developing areas are able to pasteurise their water and make it safe to drink.
While solar water pasteurisation helped, the question still remained as to which water sources were contaminated. The Portable Microbiology Laboratory (PML), designed by Dr Metcalf, contains tests for E. coli. Each PML includes 25 inexpensive and easy-to-use water tests. Using principles and methods from food microbiology, the PML is able to accurately test water in rural areas without the need for electricity, running water, or the expensive laboratory equipment normally needed.
In 2007, as part of its Safe Water Project (SWP), SCI began teaching Kenya's rural health workers how to test water sources using the PML and how to treat contaminated water with a solar cooker and a WAPI. The PML can be used anywhere by practically anyone, and is currently helping Kenyan government ministries in charge of water analysis who have had difficulties gauging water quality in rural areas due to travel limitations and technical expenses. Anticipated outcomes from the SWP include significant reductions in the incidence of waterborne diseases in over 20 communities, and broader community awareness of simple and effective water testing and water pasteurisation techniques. In June 2008, PML was used to help contain a cholera outbreak in Kenya's Nyakach region near Lake Victoria.
SCI is also now exploring collaborations with local solar lighting companies to meet another express need of those who benefit from its programmes.
Successful execution of solar cooking and water treatment programmes in developing areas can drastically decrease hunger, respiratory and waterborne diseases, and deforestation; increase food security, school attendance, and income generation; and empower women by providing entrepreneurial prospects and participation in micro-business.
By Karyn Ellis
Director of International Programs
Solar Cookers International
The Public Service Review is an online publication based in the UK.
To see the article, click on the PSR link on the right and go to Water, Sanitation and Hygiene under Contents on the left.