Something to smile about

According to Water.org, about 2.6 billion people, approximately half of the developing world’s population, lack even a simple ‘improved’ latrine and 1.1 billion do not have access to improved drinking water. These people obviously inhabit the poorest countries and the ninth poorest country in the world is Madagascar, which unlike most of the countries below it in the list is not in a state of conflict, it is just inherently poor.

From a sanitation perspective around 22 million of Madagascar’s 24 million population don’t have access to a safe toilet – improved sanitation that meets health and safety standards. What is more is that every year much of it is prone to flooding, meaning buried waste does not stay buried for long. It is a massive problem.

A start-up in South London has developed a solution and trials in Madagascar’s capital, Antananarivo, have already proved promising. It started at the Royal College of Art with a master’s degree project from Virginia Gardiner, who is now CEO of Loowatt.

The philosophy was not just to create a toilet, but a whole closed loop system that produces energy and fertiliser rather than waste. There are several components to this system – the toilet itself, waste collection and the processing of that waste.

The clever bit is the design is the toilet. Kaitlin Zhang, public relations and brand manager at Loowatt, outlines the operation: “It has a biopolymer film inside it, and that is taken down through the toilet in what we call a ‘flush by the mechanism’ inside, and that’s where the first one of our patents is based.And then that waste is captured within that film, and that means that anyone handling it doesn’t come into direct contact with that waste.”

Tsiky, the Madagascan word for ‘smile’ is the name given to these toilets, and another reason to smile is that the flush system creates a continuous mechanical seal, which means that odours do not come back up. “This is quite exciting, because that’s one of the things that we wanted to solve,” claimed Zhang.

Another thing requiring resolution was the quality of the finish in the end product. Two years ago the company was growing fast as it progressed from the prototyping and trialling stage.Chris Holden, the company’s head of design, commented: “We were looking at the issues of ramping up quickly and understanding product lifecycle and just having good systems and processes in place. We were also in some respects starting afresh in terms of the design because we didn’t have a particularly great finish to the product. So we were looking at that and just came across the opportunity that Autodesk had with Clean Tech Partners that fitted really well. It actually really suits us because we have an engineer and a designer in Madagascar working on things like the superstructure.”

The superstructure needs to be altered for every installation depending on how the Tsiky is sited. As the Clean Tech Partner programme allows licenses up to a certain value then the teams working in separate locations can work on the same designs without having to pay for the software.

Another interesting aspect of the project is how the company is supporting the project in Madagascar. Already there is an operational team of nine on the African island, but that doesn’t get round the problem of what happens when something breaks or additional parts are required.

“What we’ve seen from our work in Madagascar is that the supply chain is one of the most difficult things to get right,” admitted Holden. “There is little manufacturing infrastructure and shipping parts from the UK involves time - no one wants to wait for a toilet to be fixed and the cost imports can carry a hefty tax of up to 40%.”

The solution lies in additive manufacturing. Holden said: “We’ve been printing parts since we started because of how convenient it is and it provides pretty good value as well when you want to make a custom part in small volumes. It’s an option we’re definitely going with in the short term and what we want to find out is does it translate into a large-scale solution for us?”

Currently the company has an Ultimaker in the UK for prototyping and a RepRapPro printer in Madagascar, mainly used for printing the flush mechanism gears and associated components.

Waste processing

Loowatt has designed a small digester (25m³) but there is no reason why other commercial operations cannot be used. The key point is that the bag material is biodegradable ensuring that from toilet to digester there is no part of the cycle where waste is exposed and therefore can come in contact with users or operators.

Zhang explained how the waste is processed: “A biological process [anaerobic digestion] first of all breaks all the waste down to acids and then micro-organisms eat the acids and create the biogas.”

Biogas is two thirds methane, which is clean burning and used to make electricity.

“But then you have the liquid by-product, which after digestion is around 95% pathogen-free,” continued Zhang. “But in our new treatment facility we pre-pasteurise the waste, so that we make sure there are no harmful pathogens going in, in the first place. Pasteurising it means you can use it as a direct fertiliser.”

To take this one step further, Loowatt is exploring the options for adding composting processes and improving the quality of the end product by using worms. Although it may seem obvious to use this fertiliser directly in the community, not all people grow their own produce. The nitrogen, phosphorus and potassium (NPK) content of the end product can therefore give it a market value.

The real value will be in improving hygiene in Madagascar and already 40 units, serving 260 people have been installed in the capital in a project funded by grants from the Bill & Melinda Gates Foundation’s Grand Challenges Explorations initiative.