Water collecting roofs, preserving our precious resources

Kollekt has the ambition to deploy easy to scale roofs, which will be placed on urban areas in order to collect the water that usually evaporates from the ground. With time, it could provide great amounts of water to cities' inhabitants.

Innovation Overview

Company name: Kollekt

Innovation name: Water collecting roof

Company motto: Water brought life, we preserve it

Innovation summary: Kollekt is a company planning on developing a water collecting solution. It consists in an easily deployable roof that can be used at any location outside: public spaces, apartment buildings, companies’ offices… This system will allow rain water to be collected, stored and extracted underground. The water collected can then be shipped towards the already existing city pipes, for whatever usage is decided by the town or region administration. Solar panels will be placed right under the transparent roof to collect UV light and create small amounts of electricity. Thus, this innovation can be useful at most times, providing more water, and using sunlight to create electricity, which can be very beneficial in areas where access to water is limited. 

Innovation functioning and features

1- How would the system work? 

This innovation would allow to collect and distribute water as follows: A roof will be deployed over a large available urban area in the city, that is not already covered. Outside parking lots, buildings’ roofs, train stations areas can be great examples of where to place this solution. The roof will be made of plastic and will be polished to allow water to flow down easily. This roof will have deeper spots where the water would be redirected, flowing down towards one final spot: a water tank, which will be placed right below ground. The water will be filtrated and treated in this tank, before a pump pushes the water down through a pipe, for it get connected to the closest city's water pipes underground. Then, the clean water can be distributed through these pipes to the closest buildings or other infrastructure that might need it. Another - and more cost saving - solution can be to decide not to filter the water, and use it for non-domestic usage, such as public gardening, industrial processes, large size cleaning etc... The small electric panels can be used to create electricity, which would have two goals. The first one is keep the water moving in the tank to avoid stale water, by a simple moving tale that will be used a few minutes per hour. The second goal would be to help providing power to the pump, which will be required to push the water through the pipe, for it to go to the city pipes. If the electricity created is sufficient, this system can be a self-sufficient sustainable solution to collect and distribute the water that usually evaporates and disappears. 

2- How would the ecosystem work? (construction, location, network…) 

These water collecting roofs can be built in many areas, and in many versions. Simple columns have to be fixed to the ground respecting certain dimensions, where the roof platforms/structures will be added on top of them, to form the overal solution. The roof's material and inclination needs to respect a specific design, in order to allow the water to fall down in the column. This column will hold a tube, that will let the water flow down directly underground, where all the small tubes will gather to reach the underground tank. This process can be repeated every time a new water collecting roof needs to be installed in a public area. For each roof created, the water collected in the tank will be going underground through a pipe that will lead the water to the city’s already existing water pipes network. Once the Kollect's water pipe is connected to the city's water pipes, the water will be merged with the rest of the public water to be distributed wherever the latter is sent to. 

3- How much can it help? 

This innovation will be respectful of the environment as these roofs will only be placed over already urbanized areas, meaning that no nature is being taken away in the building process. Moreover, it has the objective to save space, as we are not using any surface of the ground to collect water or place solar panels, but are rather taking advantage of different height levels to give one surface several purposes: the surface hosting a parking lot also hosts a water collecting system. On top of that, such innovation has the power to be scaled up, and to provide a much greater impact if these water collecting roofs are multiplied in cities. 

Let’s take a concrete example to illustrate that. This innovative roof might have been placed over a large company office building, or over a medium sized parking lot, that is 30 meters long by 30 meters large. With an average rain level of 1 meter per year, this parking would have collected in a year 900 cube meters of rain, which means 900 000 liters of water. This corresponds to the annual water consumption of approximately 20 people. Here is how one roof installed on a parking lot can entirely provide water to 20 people for a year. If this solution is scaled up to hundreds or thousands of similar rooftops across a city or region, water could be provided to several thousands of people per year, considerably helping cities. It could be used to provide water to households, company buildings, public infrastructure and more. 

4- How would it be financially/business relevant? 

This system would require strong financial support for the building phase, most likely from public and administrative organisations, who are the actors that would benefit from an extra source of water provided to the city. Thus, the main profit received by this innovation would be linked to these organisations, supporting and providing enough resources for the company to keep on developing their solution. However, external and advertising activities can be created, such as sponsoring, partnerships with other brands or participation to innovation or sustainability events, in order to help the company grow.

Regarding the costs of the solution, thanks to the solar panels included within it, it would be possible to keep low maintenance costs for each water collecting roof, as the electricity generated will be used to keep the water clean and mostly provide power to the pump. The exact maintenance costs are complex to define, but the building costs would most likely be the highest ones. The solution would aim at using an affordable plastic material for the roof, and easily deployable pillars or feet to decrease the installation costs, knowing that the solar panels installation would be an expensive part (approximately 500 euros per meter square. Finally, the connexion from each water collecting system to the city pipelines distributing the water, which will have to be repeated for each new water-collecting roof built.

Let's take a step back

Pros and cons: 

• Bigger scale than the usual rain water collection systems, only made for private houses/gardens 

• Reusing water that is never being used, as it just evaporates on cities’ asphalt 

• When no rain, the solar panels are probably at use to gather energy

• Easily scalable for higher impact

• No specific space is dedicated only to these roofs, they are added to already existing areas, as a second layer

• Used only on urban areas, preserving nature

• High efforts required for the installation and connectivity to current water pipe solution

• Profitability is not guaranteed

• Administrative and legal agreements to be found with cities’ decision makers to allow the construction of these roofs on public areas

Expansion opportunities: 

An expansion possibility could be to make the columns holding these roofs much higher, and have much wider roofs, covering urban areas of several hundreds or thousands meters square. These transparent roofs, maybe 20 or 30 meters high, would cover houses and small buildings roofs, protecting people on the ground from the rain, and using the solar panels when sun is out. It is expected for such an idea to be perceived as controversial, as it would remind people of Science-Fiction vertical cities, but if transparent and efficient, these roofs could help cities develop in a more sustainable way.

What is the main strength of this innovation?

• Collecting water that is not used in these urban areas
• Potentially highly scalable
• Not taking any space
• Solar panels increasing innovation's self-sufficient

Gallery: