Design
Introduction
The right of access to water is a fundamental human right. For the first time in history, the global demand for freshwater is overtaking its supply in many parts of the world. The U.N. predicts that by 2025, more than half of the countries in the world will be experiencing water stress or outright shortages. The former United Nations Secretary-General, Kofi Annan, states the 'Lack of access to water for drinking, hygiene, and food security inflicts enormous hardship on more than one billion members of the human family'.
Our project wants to design an optimized modular shape/surface for condensation and subsequent freshwater collection by gravity to solve the fact that in 2025, more than half of the countries in the world will be experiencing water shortage. To achieve this, our modules will be 3D printed in an innovative desiccant filament that allows us to bind ice-nucleating proteins. The project primary focus it to enable bioprecipitation and recover freshwater by passive atmospheric condensation. Being able to functionize 3D-printed shapes with biologicals has a plethora of potential applications.
Comparison to other projects
There are already some potential solutions to water scarcity based on atmospheric water generation:
- There are fog catchers in Lima, Peru. Lima receives very little rainfall during the year, but is covered in thick sea mist from June to November. By building 5 fog catchers and planting over 1000 trees they were able to use water that was otherwise not used (from the fog), instead of water from the dwindling aquifers in Lima. The planted trees, by self-irrigating, help the restoration of the natural water cycle in the region. In addition, the trees help stabilizing the hill slopes and reduce soil erosion.
- There is Watergen, a company that describes its vision as follows: “Water-gen’s vision is to provide humanity with an abundant, renewable source of fresh, clean drinking water, by extracting it directly from the air, our most abundant water resource.” The products they develop, however, need electricity, which is not always and everywhere available in Third World Contries.
- Another ongoing project is WaterSeer. It consists of a device that is planted at two meter under the ground, with a wind turbine head that sits above the ground. This turbine directs air into the underground condensation chamber, where water is collected. A pump is attached for easy access to the water.
A downside to the fogcatchers is that the presence of fog is an absolute must for the devices to collect water. This means that apart from the catchers, water tanks still needed to be installed to provide the community with water in the months where no fog is formed. A pipe installation is also needed to guide the water from the catchers to the water tanks. Apart from this, the success of this method depends greatly on the right geographical and meteorological conditions. Dewpal doesn't have these limitations, and can be used anywhere, anytime, under all kind of conditions. No complex pipe installation is needed, as gravity makes the water flow through a series of collectors to a plastic bottle acting as a water reservoir. Futhermore, fog catchers are quite big, meaning you would need more than one person to set up these nets correctly. With Dewpal, no extra help is needed. Overall, Dewpal is comparable to the fog catchers in Peru, however, thanks to the INP that is attached via synthetic biology approaches, the atmospheric water capture is expected to be higher when our Dewpal can be printed on full scale.
The main reason that our DewPal is better than Watergen is because it needs no electricity. Every Watergen product available on their site needs electricity to work. As our project is developed for use in areas where water is scarce and these areas often coincide with developing and third world countries, electricity will not be freely available at any time. This gives our project a huge advantage over Watergen. The generators are also quite large, while our device is compact and doesn't require more than one person to operate.
A major downside to the WaterSeer project is that a hole of two meters needs to be dug out to install the device. Dewpal is deployable when you get it: you just screw the water collectors on top of each other, the whole stack onto a water bottle, and you're done.
Previous projects all have a shape designed especially to optimize water capture. We did this too, based on the design in the article that can be found here. We tweaked this design so the air can enter our shape (see picture below), meaning we can collect more water than just the basic 'full sphere' structure as we have more active surface.
Also, as you can see in following simulation, the shape can be screwed on all sorts of water bottles so that the water can immediately be collected.
A comparison in the amount of water Dewpal catches and cost price should still be made. However, we do not expect this to exceed the price of previous shown projects. Dewpal is made out of low cost materials, such as PLA and biotine. As we already have the bacteria with INP attached, these only need to cultured, which also shouldn't be too big a cost. Considering all this, we expect the cost of our device to be around several euro. As for the water collection, we see our Dewpal competing with these other projects once we get to full printing size.
Lifecycle
Our Dewpal device consists of a 3D printed shape with a screwcap so it can be attached to water bottles. By doing this, our device has a positive impact on reducing plastic waste, as empty plastic bottles can now be used as a water reservoir, prolonging their life as such. As we can print our 3D shape in many different sizes, bottles of all sizes and shapes can be used as a water reservoir.
As the biological function of the device can deteriorate over time, you will have to renew your Dewpal from time to time, meaning we are still creating plastic waste. However, our shape team came up with a solution for this. The biological functional half sphere of your Dewpal can be disconnected from your screwcap bottom, meaning the screwcap bottom could have a nearly endless life time, while only the biologically functional part would need replacement from time to time. This disconnected half sphere could then again be coated with bacteria to prolong its life even more. Note that this design isn't implemented yet by our shape group, but will be in the future.