A new kind of low-cost waste treatment plant that turns sewage into clean drinking water and electricity has been developed, offering a unique solution to sanitation in developing countries.
The Omni Processor, designed and built by Seattle-based engineering firm Janicki Bioenergy, received funding from the Bill and Melinda Gates Foundation and was tested out by Bill Gates on a recent trip to the plant.
"The water tasted as good as any I've had out of a bottle," Gates wrote in a blogpost. "Having studied the engineering behind it, I would happily drink it every day. It's that safe."
The Omni Processor is capable of handling waste from 100,000 people, producing up to 86,000 litres of potable water and 250 kw of electricity every day.
A pilot project of the machine is planned in Dakar, Senegal, next month, while other partners in developing countries are currently being sought.
"Model S100 is scheduled to ship to Dakar, Senegal, in mid-February 2015," Janicki Bioenergy's website states. "This location is perfect for continuing development and measuring real-world performance.
"We are very dedicated to making sure that the Omni Processor works reliably in all locations, and Dakar provides us with an opportunity to establish our support channels, supply chains, and logistics in Africa."
The firm claims that water produced from the sewer sludge is no different to bottled water. By boiling the sludge and filtering the vapour produced to remove harmful particles, it is ensured that the water produced is bio-safe.
"Through the ingenious use of a steam engine, it produces more than enough energy to burn the next batch of waste," Gates said. "In other words, it powers itself, with electricity to spare.
"It might be many years before the processor is being used widely. But I was really impressed with Janicki's engineering. And I'm really excited about the business model. It's the ultimate example of that old expression: one man's trash is another man's treasure."