Tag Archive: clean water

The Fog Catchers

Water is as important as energy in many communities. This is the case in developed and developing countries. These energy efficient examples of harvesting water from fogs or mists which often occur even in the direst countries (especially near the coast) are an important development.

The following are an example of several entities, many not for profit, undertaking projects around the world.




FogQuest is a Canadian non-profit that uses modern fog collectors to bring drinking water and water for irrigation and reforestation to rural communities in developing countries around the world. Their fog collectors can be used in dry regions and even deserts that receive less than one millimeter of rain each year. But to work, they do require fog and light winds.

FogQuest builds upon the experience gained in projects conducted since 1987, which have repeatedly shown the viability and effectiveness of using fog collectors to produce clean water for people in developing countries worldwide.

Miracle in the Mist
The following video was produced by journalist Lauren Millar for the series Journeys on TVOntario. It was shown extensively on TVO and Discovery Channel in the mid-1990s. It is now on YouTube and provides helpful background on starting fog collection projects in developing countries. These projects in Ecuador were initiated by Bob Schemenauer and Pilar Cereceda in the years before FogQuest was established.

Website: http://www.fogquest.org




By utilizing natural and local resources, the DropNet could greatly improve the drinking water supply in many isolated areas that have limited infrastructure. This fog collector filters tiny water droplets from fog clouds and causes the droplets to coalesce. Each unit can collect 10-20 liters of water per day, and an array of several structures could easily supply a whole village with clean healthy drinking water. Due to its tent like construction the DropNet collectors can be assembled by non-skilled workers on both flat and uneven grounds.

While studying Industrial Design at Germany’s Muthesius Academy of Fine Arts and Design, Imke Hoehler based her final thesis on finding a resolution to this important challenge. Her DropNet fog collector offers a versatile design that literally harvests drinking water from thin air and mist. This easy to assemble design could have a significant impact on the bleak and waterless future many climate scientists believe to be inevitable.

Alisios: agua de niebla

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Developed over the past 5 years on the Canary Islands by Hernando Theo Olmo and Ricardo Gil, the “Water Gardens” are groupings of water-extracting towers for high volume and high quality water. Some of the planned uses are for forests, camping, fire suppression, agriculture, livestock, and human consumption.

According to the website; After years of experimentation and improvement, our NRP 3.0 fog collectors are currently the most technically advanced and productive in the world in the last 50 years in this sector, with a maximum collection of 1,074 liters / day and a life of more than 10 years.
The NRP 3.0 fog collector, have a huge collecting surface of 56 m2 into minimum space, only 1.6 m2, thus reducing the area occupied by 90% and minimizing the visual impact. Its three-dimensional structure gives great stability and prevents the loss of water out of the structure and also minimizes the influence of the wind direction in production of water. It also has a base designed to decant and filter the water before it passes to the tube system.
The materials used give the NRP 3.0 high strength, low weight and high durability.
Due to the rate cost-production, this system allows us to consider definitely the mists as another water resource, complementary to the existing resources, and this,  in a practical, cost-effective, sustainable and innovative. Water from the mist can be used for qualitative and quantitative improvement of the waters from another origin, which can also help  to reduce transportation costs, pumping or treatment of these, saving energy and minimizing pollution.

Website: http://eng.aguadeniebla.com/index


Technion is an Israel Institute of Technology, has come up with an unusual water extraction concept. Two architects invented this low-tech way of collecting dew and turning it into fresh water. It works well for collecting water in virtually any environment, even in polluted areas. About 12 gallons of fresh water can be extracted from air in a single day from one 300 sq ft unit. This technology recently won an international competition.


Future Possibilities

This is a concept  out of Chile. It was a winner of the Holcim Awards “Next Generation” prizes for project visions
For the first time in 2008 , the Holcim Awards competition included a category for the visions of young architects and designers. First prize was presented to architect Alberto Ferandez Gonzalez who was applauded for his coastal fog-harvesting tower concept for Huasco, Chile, which proposes to extract water for agriculture from the “Camanchaca” coastal fog. “Next Generation” 1st prize: Coastal fog-harvesting tower, Huasco, Chile: The tower is 200m high, catching each water particle in the air that comes from the coast to the valley of Huasco River.

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Energy, Clean Water & Hydrogen from One Material


A new wonder material that can generate hydrogen, produce clean water and even create energy. Multi-use Titanium Dioxide (TiO2)


Webbanner Assoc Prof Darren Sun

Assoc Prof Darren Sun

Titanium Dioxide (TiO2)

We covered this story earlier on and I wanted to revive it. It first broke in March. I had a message from one of the good people from the Global Breakthrough Energy Movement showing that this story is still getting a lot of attention. We cover energy subjects here but water is just as important , if not more so in many communities around the world and is in serious short supply. Access to clean affordable water is just as important as having energy independence.

I am also taking this story very seriously as More than 70 scientific papers on Prof Sun’s work in titanium dioxide has been published in the last five years, the latest being papers published in Water Research, Energy and Environmental Science, and Journal of Materials Chemistry. Prof Sun, 52, from NTU’s School of Civil and Environmental Engineering, said such a low-cost and easily produced nanomaterial (TiO2) is expected to have immense potential to help tackle ongoing global challenges in energy and environmental issues.

Prof Sun claims multi-use titanium dioxide can:

1. concurrently produce both hydrogen and clean water when exposed to sunlight
2. be made into a low-cost flexible filtration membrane that is anti-fouling
3. desalinate water as a high flux forward osmosis membrane
4. recover energy from waste desalination brine and waste water
5. be made into a low-cost flexible solar cell to generate electricity
6. doubles battery life when used as anode in lithium ion battery
7. kill harmful microbial, leading to new antibacterial bandages

I am not sure how well the material compares with other materials for achieving any of the above claims on an individual basis. It does however allow for the engineers to come up with some interesting combinations and solutions. It a little like discovering electricity…..now we have it what do we do with it.

After the following press release I have linked several videos that shows other research and applications of TiO2

The good news is NTU is willing to work with commercial partners to fast track this material. I hope many of our readers will have their imaginations stimulated to look at possible solutions and uses. The following press release came out in March but it appears it is now really gaining some traction.

Press Release March 2013

It can also desalinate water, be used as flexible water filtration membranes, help recover energy from desalination waste brine, be made into flexible solar cells and can also double the lifespan of lithium ion batteries. With its superior bacteria-killing capabilities, it can also be used to develop a new type of antibacterial bandage.

Scientists at Nanyang Technological University (NTU), led by Associate Professor Darren Sun have succeeded in developing a single, revolutionary nanomaterial that can do all the above and at very low cost compared to existing technology.

This breakthrough which has taken Prof Sun five years to develop is dubbed the Multi-use Titanium Dioxide (TiO2). It is formed by turning titanium dioxide crystals into patented nanofibres, which can then be easily fabricated into patented flexible filter membranes which include a combination of carbon, copper, zinc or tin, depending on the specific end product needed.

Titanium dioxide is a cheap and abundant material, which has been scientifically proven to have the ability to accelerate a chemical reaction (photocatalytic) and is also able to bond easily with water (hydrophilic).

With the world’s population expected to hit 8.3 billion by 2030, there will be a massive increase in the global demand for energy and food by 50 per cent and 30 per cent for drinking water (Population Institute report, titled 2030: The “Perfect Storm” Scenario).

“While there is no single silver bullet to solving two of the world’s biggest challenges: cheap renewable energy and an abundant supply of clean water; our single multi-use membrane comes close, with its titanium dioxide nanoparticles being a key catalyst in discovering such solutions,” Prof Sun said. “With our unique nanomaterial, we hope to be able to help convert today’s waste into tomorrow’s resources, such as clean water and energy.”

How the wonder material was found

download (21)Prof Sun had initially used titanium dioxide with iron oxide to make anti-bacterial water filtration membranes to solve biofouling – bacterial growth which clogs up the pores of membranes, obstructing water flow.

While developing the membrane, Prof Sun’s team also discovered that it could act as a photocatalyst, turning wastewater into hydrogen and oxygen under sunlight while still producing clean water. Such a water-splitting effect is usually caused by Platinum, a precious metal that is both expensive and rare.

“With such a discovery, it is possible to concurrently treat wastewater and yet have a much cheaper option of storing solar energy in the form of hydrogen so that it can be available any time, day or night, regardless of whether the sun is shining or not, which makes it truly a source of clean fuel,” said Prof Sun.

“As of now, we are achieving a very high efficiency of about three times more than if we had used platinum, but at a much lower cost, allowing for cheap hydrogen production. In addition, we can concurrently produce clean water for close-to-zero energy cost, which may change our current water reclamation system over the world for future liveable cities.”

Hydrogen is a clean fuel which can be used for automotive fuel-cells or in power plants to generate electricity.

Producing hydrogen and clean water

This discovery, which was published recently in the academic journal, Water Research, showed that a small amount of nano material (0.5 grams of titanium dioxide nano fibres treated with copper oxide), can generate 1.53 millilitre of hydrogen in an hour when immersed in one litre of waste water. This amount of hydrogen produced is three times more than when Platinum is used in the same situation.

Depending on the type of waste water, the amount of hydrogen generated can be as much as 200 millilitres in an hour. Also to increase hydrogen production, more nano material can be used in larger amounts of waste water.

Producing low-cost flexible forward osmosis membranes

Not only can titanium dioxide particles help split water, it can also make water filter membranes hydrophilic – allowing water to flow through it easily, while rejecting foreign contaminants, including those of salt, making it perfect for desalinating water using forward osmosis. Thus a new super high flux (flow rate) forward osmosis membrane is developed.

This discovery was published recently in last month’s journal of Energy and Environmental Science. This is the first such report of TiO2 nanofibres and particles used in forward osmosis membrane system for clean water production and energy generation.

Producing new antibacterial bandages

With its anti-microbial properties and low cost, the membrane can also be used to make breathable anti-bacterial bandages, which would not only prevent infections and tackle infection at open wounds, but also promote healing by allowing oxygen to permeate through the plaster.

The membrane’s material properties are also similar to polymers used to make plastic bandages currently sold on the market.

Producing low-cost flexible solar cells

Prof Sun’s research projects have shown out that when treated with other materials or made into another form such as crystals, titanium dioxide can have other uses, such as in solar cells.

By making a black titanium dioxide polycrystalline sheet, Prof Sun’s team was able to make a flexible solar-cell which can generate electricity from the sun’s rays.

Producing longer lasting lithium ion batteries

Concurrently, Prof Sun has another team working on developing the black titanium dioxide nanomaterial to be used in Lithium ion batteries commonly used in electronic devices.

Preliminary results from thin coin-like lithium ion batteries, have shown that when titanium dioxide sphere-like nanoparticles modified with carbon are used as the anode (negative pole), it can double the capacity of the battery. This gives such batteries a much longer lifespan before it is fully drained. The results were featured prominently in a highly respected Journal of Materials Chemistry on its cover page last year.

Next step – Commercialisation

Prof Sun and his team of 20, which includes 6 undergraduates, 10 PhD students and 4 researchers, are now working to further develop the material while concurrently spinning off a start-up company to commercialise the product.

They are also looking to collaborate with commercial partners to speed up the commercialisation process.

For more information, visit;  www.ntu.edu.sg

 Link : http://media.ntu.edu.sg/NewsReleases/Pages/newsdetail.aspx?news=14e3b618-c71c-4f20-935c-2a566af5a298

Other Research and Video’s

The following is a collection of videos of experiments, applications and research with  TiO2

Studying titanium dioxide with photoemission at MAXLab in Sweden

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Self-cleaning and micrometric titanium dioxide

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Titanium Dioxide Raspberry Solar Cell

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Titanium Dioxide Photoelectrochemical Cell (High School Experiment)

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Application of Nano Titanium Dioxide Coating in a Dental Clinic

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