Bill Gates has proven his commitment to raising awareness of the issues around sanitation and its importance to economic and social development in emerging markets, by drinking water made from human waste.
The iconic moment was captured on video as Gates consumes the distilled water through the technology developed by Janicki Bioenergy, a small engineering firm based outside of Seattle, works.
As Gates notes in his blog post on the new technology, sanitation in developing countries is a huge problem. Poor waste disposal causes the deaths of hundreds of thousands of children each year and prevents them from developing both mentally and physically.
"If we can develop safe, affordable ways to get rid of human waste, we can prevent many of those deaths and help more children grow up healthy," Gates writes.
The Bill and Melinda Gates Foundation is backing a pilot project for Janicki's project in Senegal later this year.
The technology isn't particularly groundbreaking. Distillation, which purifies a liquid by heating it to a vapor then condensing it, is a basic principle of high school chemistry. Evaporating the water vapour from waste sludge and condensing it creates the water, which is then purified. The remaining sludge is then heated in a steam engine and runs a generator to produce electricity.
Water from waste (or blackwater) has been a hard sell in many geographies, and in the developing countries that Gates targets, there's an operational challenge in collecting the waste before it can be purified. Some startups like the MIT spinout, Sanergy, are working on solving the problem of waste detection.
In Gates' post on the technology he seems to indicate that the company will rely on truckers to take the waste to the Omniprocessor facility designed by Janicki Bioenergy.
"The sanitation system as we know it in the developed world cannot work in developing countries. So what we need in developing country is very simple systems," says Doulaye Kone, senior program officer at Bill and Melinda Gates Foundation.
The next-generation processor will be designed to handle waste from 100,000 people, which can produce up to 86,000 liters of potable water a day and a net 250 kw of electricity, according to Gates. If it helps even one family get a glass of fresh water, it seems well worth.