Solar Water Pasteurizer

Our solution is an affordable, sustainable and scalable way to eliminate diarrheal pathogens from drinking water in distressed urban communities worldwide, and thereby dramatically reduce diarrheal morbidity and mortality. This point-of-use innovation uses only renewable energy (sunlight) and the greenhouse effect, to produce safe drinking water.

Procuring safe drinking water is one of the greatest daily challenges for communities in resource-poor regions around the world.

In these communities, fecal contamination of drinking water sources leads to chronic levels of diarrhea, one of the top three causes of child morbidity and mortality worldwide. 

Where point-of-source water treatment and distribution systems are unavailable, local populations resort to point-of-use treatments, the most common being boiling water. But boiling water is not only unnecessary, but also creates indoor and outdoor air pollution, and burn and fire hazards. Solar pasteurization is a simple, superior solution.

The hypothesis is that the rate of adoption of a new technology is negatively associated with the burden of use, and positively associated with the severity of the problem and fit with daily routines.

To test this theory, a small field trial of the innovation was conducted in two urban slums in Dhaka in 2014. The devices were distributed to twenty households in two very poor, severely water distressed communities (measured by lab tests).

The trial indicated device adoption rates of 90%, and a stark reduction in the rate of incidence of diarrhea among young children in the participating households.

There are two target outcomes. One is to devise a solution that is practical, easy to use, and scalable, the better to promote adoption and regular use by water distressed households worldwide.

The second target outcome is measurable reduction in the rate of incidence of diarrhea in children five years of age and under in households who have adopted the solution. 

The population that will most benefit from the solution is the one most vulnerable to diarrhea: young children in resource-poor communities. 

The point-of-use device will be distributed to participating households. The device is portable, and lightweight. 

Random visits to households and chemical tests of the drinking water, to ensure treatment. - Uptake of device

Self-report of incidence of diarrhea among children by the primary caregiver in the participating household. - Rate of incidence of diarrhea

Unlike other solutions, this one combines multiple benefits:

It uses only sunlight as a power source - renewable energy

It is affordable, and uses only locally available inputs

It is easy stored, and portable

It leaves no carbon footprint, and prevents air pollution

It saves households from burning fossil fuel to boil water

It can be easily maintained by the consumer

The solution is human-centered because it is point-of-use. It functions and provides benefits without large infrastructure investments or other networks or systems. As such, the solution is ideal for poor, distressed, disaster-prone regions and communities, or conflict zones.

In its current form factor, the solution can be not only operated and maintained, but even potentially assembled in the communities for which it is designed. 

The process for treating water, as demonstrated in the video, can be performed by any member of the household, without assistance or intervention by professionals. 

The solution is portable and lightweight, and can be distributed to target communities, to be deployed at point-of-use, by various suppliers, local governments, or by members of the target communities. The solution requires minimal training to operate.

In its current form factor, the innovation costs less than US$30 in inputs that are readily available in developing economies - foam, wood, tape, plastic bag. There are no circuits, expensive materials, or software. 

In the proposed, more resilient form factor, the design will require assembly by a plastics plant, but remains practical and suitable for resource-poor communities. 

Team members are academics, who are pursuing this research as paid employees of academic institutions. 

Research funds and resources for developing of solution to date have been provided by the Government of Bangladesh, and Uppala University, Sweden.

We need assistance to obtain the funds necessary to pilot and scale the solution. 

The primary limiting factor is burden of use. This is a significant obstacle in adoption of new technology or new solutions. 

Therefore, for the solution to succeed, the development path needs to reduce this burden of use. 

Based on surveys conducted during the preliminary 2014 field trial, the burden is the handling of the plastic bag. Thus the desired form factor is one that eliminates the plastic bag, in favor of a molded plastic device. 

We are applying to Solve because we want to create a practical, resilient, scalable device for producing clean drinking water, with a low burden of use, and implement the solution where it is needed. But we cannot do this by ourselves. 

We have taken the innovation to a certain point; now we need assistance from potential partners with complementary aptitudes and resources to make further progress.

Specifically, we seek to find collaborators to develop more resilient version of the technology, with lower burden of use: a compelling form factor for the solution.

Currently, the team working on the solution is a partnership between Dhaka University, Department of Biomedical Physics and Technology, Dhaka University Department of Economics, and a researcher from the University of Liberal Arts, Bangladesh. 

Uppsala University, Sweden, also provided resources to develop the solution. 

Our media partner is Pinhole Films.

We do not have competitors in Bangladesh; no other parties here are using this technology.