Salt water lamp WaterLight set to power communities without electricity

The portable device takes inspiration from indigenous practices at the borders of Venezuela and Colombia.

Colombian renewable energy start-up E-Dina and WPP’s Wunderman Thompson Colombia division have developed a device which converts salt water into electrical power.

WaterLight is a portable light that can turn half a litre of salt water into 45 days of light, according to Wunderman Thompson.

It has been prompted by the World Health Organisation (WHO) which showed 840 million people worldwide are currently without access to electricity.

Meanwhile, worldwide demand for electricity continues to grow anually and traditional fossil fuel resources are set to deplete.

How it works


WaterLight works through ionisation. Electrical energy is produced when salt water electrolytes react with magnesium inside the device.

As well as a portable light source, WaterLight also charges small devices through a USB port. In emergency situations, it can be powered by urine.

Wundermann Thompson explains that inspiration came from traditional practices of the Wayuu, an indigenous community in the La Guajira peninsula on the Colombia-Venezuela border.

The desert landscape is surrounded by the sea and has limited access to electricity. It’s hoped that the WaterLight will help the community use the sea water to sustainably power their lives without needing to travel to find power. One intended use is to help night fishing, for example.

WaterLight is decorated with traditional symbols and patterns while the wooden surface echoes the ancient art of Kanas weaving. The strap has been created by local craftswomen and incorporates artisanal methods.

The device is waterproof and made from recyclable material and has an expected lifetime of around 5,600 hours which equates to two or three years of use, according to Wunderman Thompson.

Wunderman Thompson global chief creative officer Bas Korsten says: “WaterLight demonstrates how the holy trinity of technology, creativity and humanity can produce a genuinely groundbreaking idea – one which holds the potential to transform life for millions of people.”

WaterLight is poised for a worldwide roll-out, according to the company, adding that many nations such as Sierra Leone and Syria are in  similar positions to La Guajira.

The product is available for purchase by NGOs, governments and private organisations.

Hide Comments (12)Show Comments (12)
  • Neil Littman April 19, 2021 at 10:29 am

    Absolutely brilliant. I can think of a lot of other commercial applications that it could be used for. Also I wondered why such a product has not been available much sooner if the principles were already understood?

  • lien backwards April 25, 2021 at 3:06 pm

    Throws a whole new………….Totally briliant, every one could do with one of these

  • Dinesh Panchal June 24, 2021 at 10:31 am

    I like to have this water light made in India as many people can use it who have no light near by and during travelling by night in small villages from Farm to home
    or on the dark street. If we can get support from Colombia party we can co operate very nicely to serve poor peoples here.

  • Gadepalli Subrahmanyam August 29, 2021 at 3:21 pm

    Mr. Panchal,
    Could you get in touch with me .
    [email protected]/9652837050

  • Tomáš Slouka September 24, 2021 at 7:16 am

    It is a battery. Salt water is an electrolyte and it contains two metallic electrodes. Those electrodes probably won’t be renewable like wood is. So… this is just a glorified battery, nothing revolutionary, nothing purely ecological,

  • Leo Robert Burgunder October 2, 2021 at 3:34 am

    We know the anode is Mg but the cathode material is not specified. Could be carbon. Also not sure how many cells but I think this could also be made from a Zinc or Aluminum anode and Copper cathode cells and pvc pipe fittings as a 8th grade science project. The number of LED’s would dictate the # of cells and lumens emitted. The 5600 operating hour claim seems to good to be true without recharge.

  • jeff didomenico October 11, 2021 at 7:56 pm

    I would love to contribute to this program, who can I speak with ?

  • Lolismo December 30, 2021 at 2:42 am

    So how is this different from using a disposable quadruple A battery?

  • Paul Schifferes March 17, 2022 at 3:26 pm

    This doesn’t “convert salt water to power”. That would be magical.
    The energy comes from the electrode potential of the magnesium, and that will run out as it’s oxidised. The magnesium has to be made by electrolysis in an industrial process. The cathode is copper I think, which also comes with an evolutionary impact. So much reporting on this shows remarkable ignorance of basic chemistry.
    This may be a particularly long life battery, but this is essentially the same battery technology (two metals with saltwater between them) that was used by Volta in the 1790s!

  • Peach L March 18, 2022 at 1:15 pm

    If DesignWeek2022 is considering this device for an award or even featuring it on its website, the organisation really needs to take a good look at itself.

    Debunking the claims:
    1. “WaterLight is eco-friendly, being 100% recyclable and waterproof.” *The magnesium block in the device will be used up in the process, and magnesium chloride salt and caustic Sodium Hydroxide (lye) will be produced. For the magnesium to be recyclable, you’d need to send the salt and the lye to a chemical plant. The impression given in the video is that the device is used in a less developed location. It is unlikely there will be a chemical plant there, hence the 100% recyclable claim is bogus.*
    2. “So, it’s durable and sustainable, regardless of where it ends up.” *Recovering the magnesium from magnesium chloride will cost a lot of energy, not to mentioned the energy involved in transporting the magnesium chloride to the chemical plant and the energy for running the equipment in the plant. It is a poor use of magnesium and it cannot be considered as sustainable.*
    3. “This incredible lantern utilizes the ionization of an electrolyte composed of saltwater, which converts the magnesium inside the lantern.” *What BS is this? The saltwater is the only electrolyte and it is already ionised, while at the sea. There is no need to put it into this device beforehand.*
    4. “This small yet mighty circuit makes it possible to extract around 500 watts for each liter of water!” *’Watts’ is not the correct unit to indicate the amount of energy you can draw from the device. It should be in joules/kilojoules and sometimes milliampere hours together with the voltage. Also, the electrical energy comes from the magnesium, not from the saltwater, which is just there to conduct the electricity. Using ‘watts’ or its equivalent, joules/sec, and saying the energy come from the saltwater just indicate the narrator doesn’t understand the shit he’s saying.

    A magnesium-copper battery like this will generate about 2.7 volts. If the 500 watts figure is correct, it means the device has 185 000 milliampere hours of charge. A current premium smartphone has 5000 milliampere hours of charge, which means this device has 37 times the charge of a premium smartphone! That’s hard to believe.

    5. “Waterlight’s possibilities are endless.” *No, it’s not. After the 45 days, the lantern will stop working and it is thus not “endless”. It will require a major replacement of the magnesium inside to make it work again, but how will you easily find a block on magnesium in a less-developed location? A solar-rechargeable lantern is so much more re-usable.*

    6. “It can benefit off-grid communities in need of an electrical source to supply light, charge a cell phone, or listen to a radio.” *While the device can charge a cell phone, the magnesium will be quickly used up and the device’s life will be greatly shortened if used for this purpose.*

    7. “…and education – for turning on a computer or a television.” *If you have the electricity to turn on a computer or a television, why would you need this weak lantern to light up your surroundings?

  • Rarius June 16, 2022 at 8:12 pm

    This is just an disposable magnesium/copper inefficient battery with an LED.

  • John Crow September 24, 2023 at 10:30 pm

    I have to agree this is a hyped up marketing campaign to sell a not so sustainable battery powered lamp to ignorant and gullible NGOs and governments. someone is on the make

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