Markos Manolopoulos shines a light on EcoSwell, an NGO making waves with solar distillers in Peru and beyond.

The solar distiller is a simple piece of technology that can be used to combat water scarcity in remote areas. A straightforward description of it would be that it uses the heat from the sun to make dirty water or seawater drinkable, through the process of distillation. I’ll go into more detail about this process below, but that’s the basic premise of the technology.

I first came into contact with solar distillers when volunteering with the non-governmental organisation (NGO) EcoSwell, based on the northwest coast of Peru. EcoSwell work to holistically develop their local community, Lobitos (although they have now expanded to other towns too), using a variety of different programmes to address the key issues faced by the community. These include deforestation, pollution, power cuts, and yes, water scarcity.

To understand the problem of water scarcity in Lobitos, a brief background on the geography of the town as well as the water infrastructure in Peru as a whole is required.

Lobitos is located on the north-western coast of Peru, in the province Talara. This is just south of the Equator, meaning the weather is quite stable throughout the year and, of course, very warm. The area is classified as a ‘hyper-arid’ zone due to the extremely low amount of rainfall they receive each year – on average just 10-15 mm, compared to the 800 – 1400 mm we get in the UK. However, this is far from representative of the geography of Peru as a whole, which can instead be understood in three broader classifications: the arid area on the western coast, the Andes mountains across the middle of Peru, and then the beginnings of the Amazon rainforest and the Amazon basin in the East.

Peru does in fact have significant levels of freshwater, constituting nearly 5% of the world’s renewable water sources, yet around 2 million people lack access to an improved water source and 4 million lack access to improved sanitation. This is largely due to the difficulty involved in transporting the water from its supply, through the rugged Andean terrain, and finally to the most remote regions in the west.

What this means is that those in western areas heavily rely on the transportation of water to them, both by rivers and man-made infrastructure. Put simply, they are last in line to receive the water by nature of their geographical position.

More recently, the situation has gone from bad to worse. Previously, a significant amount of water used for agriculture in the regions surrounding the Andes came from glacial melts in the summer months. However, over the past 50 years these glaciers have lost around 40% of their surface area due to rising global temperatures, meaning this essential supply of freshwater is now vanishing fast. To add to the this, the rapid thawing of the glaciers has exposed metals deep within their interior, contaminating what little water is left coming off the mountainside.

“In Peru, 2 million people lack access to an improved water source and 4 million lack access to improved sanitation.”

Couple all of this with an increasing frequency of droughts in the region, and you get more and more farmers pulling water from the national infrastructure before it reaches the northwest. Not only that, but the northern coast itself has a significant oil industry, a water-intensive operation, which also draws from this limited supply meant for humans.

All of these issues are then compounded even further during the climate phenomenon known as “El Niño”, where storms create landslides that impact the water infrastructure of Peru and can leave towns like Lobitos without water for several weeks or months. El Niño is projected to become more impactful amid climate change, with increased rainfall and possible increased frequency leaving these towns stranded for greater lengths of time.

So how does all of this impact the day to day lives of the people in Lobitos? Well, for a start there is an irregular supply of water to the town, and when the water does come it is often dirty given how far it has been transported. In a good week locals can access water 2-3 times, for a few hours at a time, meaning people must collect as much water as possible in plastic containers and then boil it before using as required.

Alternatively, families can consume plastic bottled water, transported by truck to the town at a high financial and environmental cost (not only is this a carbon intensive journey due to the shear miles driven, but it is also damaging the fragile ecosystem in the area as Lobitos lacks sufficient waste management facilities to deal with the plastic).

Overall, water is a daily worry that occupies the lives of people in this community, and the many others like it. Having regular access to it is a worry, storing it is a worry and disposing of it is a worry.

How then can we improve the water security of Lobitos? Is there an option that will not create another host of issues, like plastic bottled water?

The answer is quite simple – use the resources abundant to the people of Lobitos. The town is a coastal community, meaning water is abundant, you just need to know how to use it.

“The solar distiller can produce 2 – 3 litres of distilled drinking water per day.”

This is where the solar distiller comes into play: the distiller uses the simple process of distillation to produce drinking water from seawater. Simply fill it with seawater in the morning, close the lid and then wait for the heat of the day to increase. Inside the distiller temperatures rise to between 85 and 95 ᵒC, evaporating the water (leaving the salt behind), which then condenses on the distiller lid. After this, the clean, salt-free, water runs down the glass lid (which is why it is set at an angle) to the collection jar at the bottom. The distiller must then be cleaned to remove the brine (a small amount of water with a high concentration of salt) and whatever dirt was in the seawater.

In total, the process can generate 2 – 3 litres of distilled drinking water per day, and the distiller itself can last around 5 years. They’re built by local tradesmen using local, largely biodegradable, materials. This is truly a sustainable source of water that does not lead to excessive pollution of the local environment and crucially, is extremely reliable.

It is perfect for Lobitos as its most abundant resources (sun and sea water) can now be used to provide their most scarce resource – clean drinking water. Now, EcoSwell have now finished testing their final prototype, the product of several years of research, that they will begin to scale up locally.

The town of Lobitos, northwest Peru, receives piped water just 2 -3 times per week.


But the problem of water scarcity in coastal communities is not unique to Lobitos; this technology could be beneficial to towns and villages the world over. EcoSwell aim to share their design globally, so that others might build and get value from it.

For example, the Intergovernmental Panel on Climate Change (IPCC) predict that the centre of Africa is likely to face rises in temperatures well above the 2 ᵒC target set out by the Paris 2015 agreement, making droughts increasingly likely. This would make vast swathes of land inhospitable, and prompt mass migrations to coastal regions which are kept cooler by the sea breeze. The IPCC estimates that with a 1.7 °C global temperature rise by 2050, 17 – 40 million people could migrate internally in sub-Saharan Africa, increasing to 56 – 86 million for a 2.5 °C rise.

This mass movement of people will surely put extreme pressures on the resources of the coastal communities, including, of course, the water. The solar distiller could reliably provide clean drinking water for such communities, especially during droughts when other freshwater sources are reduced.

This example is in a very similar vein to Lobitos, but the solar distiller does have broader applications too. Instead of distilling seawater, it could be used to distil dirty water, leaving contaminants within the distiller rather than sea salt. This can provide a much-needed source of water for communities isolated during climate events, particularly floods, which will become more common as weather systems destabilise in the coming decades.

EcoSwell have already begun sharing their designs with other NGOs, including an organisation in Madagascar, but its hard to see why this technology won’t be rolled out far and wide as the pressures induced by our warming planet increase. After all, solar distillers are cheap, can be made locally and are easy to maintain – characteristics not easy to come by when discussing the issues of water scarcity.

I do hope this is a tool increasingly used around the world, especially given that higher temperatures resulting from climate change would actually make the distiller more productive. This could become a staple piece of technology that millions of people rely upon, and while it might not completely solve some of the more complex water supply problems, its simplicity makes it an excellent starting point.

Either way, what is certain is that the opportunities presented by this technology are endless, much like its supply of water!

For more information about the work EcoSwell are doing to aid development in vulnerable communities, please visit their website: