MFA: Water bag design challenge!

Amy Smith (of MIT’s IDDS) somehow got a hold of a mic and madhouse has now ensued! Everyone has been split up by their birth month into groups. They are given 5 water bags (sachets) and told to solve the world’s greatest problems. 30 minutes later we get…

5 Bag challenge

January: The Sachet Kebab
Decreasing litter and polution. People can collect water sachets off the ground easily with a pole and spiked end. It can be placed along the roads, and a lot of trash can just be spiked on the tip of it.

February: Hydro Electric
Generate electricity by using the bags to create small turbines.

March: Light absorbent and heat absorbent bags
They also had a crazy idea of drinking the water, peeing in the bag and selling that to farmers for fertilizer… to much laughter…

April: Potting and a Wallet
Drink the water and make it empty. Cut the top off and put in soil and grow small plants. Take another bag and put a small hole in it for drip irrigation. Second idea: use the bag to put your money in for when it rains.

May: The individual water-shower packet and a purse
Hang the water and put a small hole in it. Create a purse out of it to hold a camera or mobile phone.

June: Waterbelt, glasses strings
They’ve created some really interesting spectacle (glasses) holder. Also, a waterbelt to hold the water as you’re moving around.

Maker Faire Africa: Ghana 2009

July: Water purifier
Uses the light from the sun to help purify the water. It takes a bottle top cut off and used as a funnel as well. It’s shaped like a train, for marketing reasons.

August: Kids toys
Make small airplanes and hats for children and an hourglass made from 2 water bags.

September: Drip irrigation and a pillow
Puncture a bottle or a bag on top to collect water, then use for drip irrigation. Also fill multiple old empty bags with air and put them inside a pillow case to create a pillow.

October: Drip irrigation
Starts with a bag, then a tube made of old empty bags that can direct the water further and over more areas.

November: Water resistant mobile phone case
“Your phone case is not water resistant, ours is. Clap for us.”
“We have created a water wallet, not just a plastic money carrier.”

December: Water sachet lighting system and a sachet wrist watch band
Put full bags on your roof that diffuses the light and warms the water.

Distilling water from volcanic steam vents

A unique water harvesting method has been devised in the drought ridden crater of Mt. Suswa, which is dotted with continuously puffing scorching steam vents.

Tapping steam for condensation
Tapping steam for condensation

Taking advantage of the steam vents that dot this landscape, local Masai have ingeniously tapped the vents for steam that is condensed on long plastic pipes that drip continuously into drums. The local Masai claim that these vents can fill half a drum (approx 30 lt) per hour (though it seemed very unlikely to us). The water is sweet and apparently it feeds a community of several hundred people and their cattle with fresh and clean water.

We saw at tens of these contraptions in a particular zone within the outer crater of Mt Suswa. All were protected from animals by thorn bushes. There seemed to be an ownership structure amongst the users, some were better constructed, had longer pipes, were better protected and maintained. We were told that the systems were installed fifteen years earlier and it did not look like any modifications had been done since then.

pipes1

The water distilling system used here is permanent and produces a continuous supply of clean water that is collected regularly by the local community. The system we observed was in the area called Kishalu – just beyond a school. The system could be more efficient at trapping condensation – much steam was wasted as pipes were quite short, and collection drums were left uncovered and open to evaporation. The beauty of the system is that it works overnight. These water distilleries were introduced to enable the community to survive the dry season when rain water catchments had dried up.

The Suswa system is infinitely better than the water distilling process on the edge of Lake Elamentaita. Here the local Masai Women daily place a piece of zinc sheeting over a steam vent to capture condensation. They produce only 2 liters per day; a days work to produce enough drinking water for a small family for one day.

If there’s an Afrigadget award out there, the Suswa water distilleries deserve it.

josh-and-kadonyo-suswa

For more information about Mt Suswa check out Roving Rasta, and Wild about Africa for satellite images and details about hiking and caves

a tribute to SODIS

Solar water disinfection (SODIS) has been around for quite some time now and with approx. over 340.000 users in Africa alone, this low budget water disinfection “technology” is a smart approach that deserves to be mentioned on AfriGadget.

In areas where piped drinking water just isn’t available or of questionable quality, solar water disinfection is a cheap and effective method for decentralized water treatment as it can be applied at household level. It is a simple method that’s easy to teach and is designed for small scale production.

sodis1
(source )

SODIS uses solar radiation to destroy pathogenic microorganisms which cause water borne diseases:

Sunlight is treating the contaminated water through two synergetic mechanisms: Radiation in the spectrum of UV-A (wavelength 320-400nm) and increased water temperature. If the water temperature raises above 50°C, the disinfection process is three times faster. (source)

The World Health Organization (WHO) even recommends SODIS as a viable method for household water treatment and safe storage.

All you will need are clean & transparent PET bottles, fill them up with water and expose them to direct sunlight for at least 6 hours . Many people also put them on a corrugated roof (to increase temperature) and saturate the oxygen content inside the bottles prior to the sun treatment by filling them up three quarters, shaking them for 20 seconds with a closed cap on and then fill them up completely.

sodis4sodis3
(source)

SODIS may also replace the boiling of water which often requires vast amounts of firewood or other natural resources, so it not only helps people obtain safer drinking water (conventional filter candles are expensive and not always available) but also helps to preserve the local environment.

SODIS obviously can’t substitute really clean drinking water, and it often also requires pre-treatment in case the water turbidity is too high . Users can easily reduce the turbidity though by letting the bottles stand for a while until the particles settle to the ground and then also filter it through a folded cloth.

The best aspect about SODIS though – despite of it’s low budget approach – is that consumers are directly in charge of their drinking water and have a working method that enables them to treat their own drinking water.

The Swiss Federal Institute of Aquatic Science and Technology (Eawag) also published a very informative website on SODIS and provides more details about the technology as well as case studies from around the world.

Elephant Pumps

Here’s an interesting simple, low-maintenance technology:

Elephant Pumps” that were introduced to rural areas in Zimbabwe and Malawi during the last few years. These rather simple, enhanced rope pumps (based on an ancient Chinese technology) where designed for use in rural areas, where the supply of readymade spare parts isn’t that easy.

Cycle option on an Elephant Pump
Cycle option on an Elephant Pump

Now, what makes the Elephant Pump so different from the other popular low-maintenance pump “Afripump” is that it’s locally assembled and maintainable by the local community. Both systems – Afripump and Elephant Pump – may have their pro & cons (80-100m depth, high durability, low-maintenance vs. <40m depth, simple design, cheaper), but I especially like the “bicycle option” added to pumps which were built for schools:

On school pumps Pump Aid often incorporates a “bicycle” system onto the Elephant Pump since this has proved enormously popular with children. Most children in Zimbabwe have never had the chance to ride a bicycle so can even come to school early to “play” on the pump thereby helping to fill the school water tanks. The job of collecting water, once a tiresome chore, becomes fun and children no longer have to leave their classrooms to walk miles carrying buckets of water on their heads from a distant muddy pool.

The British Charity Org “Pump Aid“, which has in the past introduced and promoted these systems in Zimbabwe and Malawi for the costs of GBP 250 (~ USD 460, EUR 310) each, also created a very informative video on how the technology actually works:

“The Elephant Pump yields about one litre of clean water every second for an average well depth of 20 metres.”

It’s simple, it works, it wins! 🙂

[h/t NextBillion.net]

Keyhole Gardens

Following a story on BBC News that fellow blogger Sokari of BlackLooks had already picked up earlier in June (as well as Alison), our reader Zeno dropped in an e-mail, asking if we knew more about keyhole gardens.

Keyhole gardens?

Actually, I had heard about those Folkewall installations in Gabarone, Botswana the other day that are used for greywater recycling, but keyhole gardens were indeed quite new to me. Guess this also shows how many smart solutions still exist out there that will need to be rediscovered and put in use.

Keyhole gardens are a technique used to grow vegetables in a dry climate. They are actually a special form of raised bed gardens: circular waist high raised beds with a path to the center. Walled in by stones, there’s a basket made from sticks and straw in the center that holds manure and other organic kitchen waste for compost.
Since they look like a keyhole from above, they are often called keyhole gardens and also promoted under this name in Lesotho, where the charity organisation “Send a Cow” has been promoting the creation of these special gardens for some time now.

So what makes these gardens so special?

  • the surrounding stones retain the rich soils and keep it safe from erosion
  • the round shape retains moisture
  • compact size, even small plots can be used for gardening
  • raised beds enable the sick and elderly to help with the gardening work
  • center in the middle is used for composting and reuse of greywater (= reuse of nutrients)

“Send a Cow” also created a very informative website on their activies and published some valuable How-to-manuals for us to adopt this smart approach. Please also check out this funny animation on YouTube which puts it in plain enligsh comic style 🙂

Now I am only curious to know if we could also mix the greywater with some collected urine and use that as additional fertilizer. In any case, keyhole gardens are a very appropriate “technology” which certainly isn’t limited to countries with a dry climate.