In a country like the UK, clean water and access to electricity are two things that many of us take for granted – the average person uses 150 litres of water a day, while light is just a flick of the switch away.
In other parts of the world, however, there are plenty of countries that don’t have the luxury of fast access to water and electricity.
But a new wave of technologies is taking advantage of an abundant form of waste – and it might help to provide clean water and power for a number of countries in need.
Steam from sludge
One such technology is the Omniprocessor, a new design in sewage treatment from Seattle-based engineering firm Jonicki Bioenergy. This ‘safe repository for human waste’, funded by the Gates Foundation, can convert unmentionable ingredients into both drinkable water and electricity.
Raw sludge from the sewage system enters the machine, where it’s boiled, removing water vapour and leaving dry solids.
These dry solids are then fed into a furnace, heating it to 1,000°C and producing high-pressure steam that powers a generator.
The generator produces enough power to process the next batch of sewage, with plenty left over to send back to the grid.
The water vapour that’s removed in the initial boiling stage is run through a cleansing system, producing perfectly pure drinking water.
You might not care for where it came from, but if Bill Gates himself can happily drink straight from the machine’s tap, then it’s probably not that bad.
As well as turning human waste into valuable commodities, this revolutionary treatment process could help to prevent the dangerous waste-dumping practices that are contaminating the water supplies of millions of people.
The Omniprocessor is scheduled for a pilot programme in Dakar, Senegal , and it’s hoped that it might eventually be used all over the developing world.
Methane from muck
In India, a project by Clarke Energy uses the anaerobic digestion of bacteria to both treat the sewage and produce a useful gas: bio-methane.
This biogas can be used to as a fuel to generate electricity, powering the sewage treatment plants and providing extra electricity to be fed back in to the grid.
Sewage coming into the plant is dried and fed into a ‘digester’, where it’s naturally processed by bacteria.
The resulting gas is run through a compressor, and can then be used to power gas engines, or simply as a cooking gas. To maximise efficiency, the waste heat of these gas engines is used to heat the digester, encouraging the growth of the bacteria that digest the sewage.
As India continues to grow in population and become more urbanised, the technology could be invaluable in keeping water clean and businesses running – which is why the Indian government is subsidising clean, renewable projects like these.
The future of faeces
UK companies are also making use of sewage to generate electricity for business and domestic use.
We’ve already got a Bristol bus service that’s running on biogas made from human waste, and one UK water company generated more than 200 million kWh of energy from waste alone in 2014 – enough to power over 50,000 homes.
If we want a nation full of clean, sustainable energy – and if we want to help developing countries access clean drinking water – it may be time to get serious about sewage.