Executive Chairman & Group CEO of Dake Group, an advocate of Innovation and Sustainability – Food Security and Water Conservation.
According to a recent policy report, global water availability could become restricted enough to be considered a crisis by 2025. The United Nations puts the rate of growth in water consumption at more than twice the rate of population growth. With no resource more critical to living ecosystems than water, scarcity would lead to a collapse of food production and accelerated desertification.
More than half the world’s population lives in cities, and by 2050, this proportion is expected to increase to more than two-thirds. This rapid urbanization is beginning to overwhelm infrastructure globally. For instance, the World Economic Forum website identified the main cause of chronic water scarcity, in the southern Indian city of Chennai, as the degradation of natural and man-made water infrastructure. Curiously, the “man-made” infrastructure being referred to here included reservoirs, historically used to collect water during the city’s abundant monsoon.
Rainwater Harvesting: Capturing The Purest Water In The World
Typically, national grids rely on underground water or overground water bodies. A solution that effectively turns this model on its head is rainwater harvesting, which can take advantage of natural precipitation to add huge volumes of water to the grid.
The worldwide rainwater harvesting market reached a value of $857.4 million in 2018 and is forecast to have a value of $1,103.8 million by 2024 at a CAGR of about 4%. As the purest source of water in the world, with zero hardness and minimal chemical contamination or suspended solids, rainwater is ideal for human consumption. What’s more, not all rainwater harvesting needs to be stored in reservoirs. Planners also have the option of creating groundwater recharge infrastructure, which eliminates the need for dedicated storage or energy and chemical inputs to keep the water fresh.
The Need To Harness An Entrepreneurial Spirit
For rainwater harvesting to be implemented at a scale that results in transforming the water security of nations — especially those in arid regions — the solution needs to evolve beyond government-mandated initiatives.
Any new idea, no matter how good, needs a proactive first generation of innovators, implementors and service providers to build and operate its assets. An emerging niche industry needs to be midwifed by an entirely new ecosystem for it to expand to a size that allows it to self-propagate and thrive. However, customized business models are required for such an expansion to be optimal. Depending on existing water sources, population and primary economic activity, each region will present opportunities that are slightly different. Entrepreneurs wishing to enter the space will need to research and identify how best they can create a viable return on investment.
For instance, the availability of cheap land, which also experiences adequate annual rainfall, might encourage self-owned rainwater harvesting infrastructure. Densely populated areas, with a high premium of land, might be better suited for service providers that assist others in developing and maintaining such assets. Rainwater harvesting for agricultural purposes might be ably served by fairly rudimentary filtration, but businesses wishing to supply water for human consumption will need to factor in the cost of purification and keeping stored water fresh for extended periods. The choice of specific technologies also plays an important role in determining whether a rainwater harvesting business will be able to wean end-users away from existing water supply options. No matter how ecologically sound the strategy might be, the truth is that a sound economic model is the most effective way to ensure rapid widespread adoption.
The First Generation Of Eco-Entrepreneurs
There are encouraging signs regarding the emergence of rainwater harvesting driven businesses, and a diverse set of vigorously growing enterprises is already successfully implementing the approach.
Indian startup ThinkPhi’s “UltaChaata” product, literally translated as “upside-down umbrella,” features a raised inverted canopy, which captures up to 100,000 liters per unit during the monsoon season while generating 1.5KW of solar energy during the rest of the year.
Reyhan Jamalova, the 16-year-old CEO of Azerbaijan’s Rainergy, has introduced a solution that harvests rainwater and then generates energy by running this water through a high-speed generator, reducing carbon dioxide emissions to 10g per KW/hr.
One of our products, IDER range, transforms ordinary sand to allow the passage of air while retaining water. The range features pavers and kerbstones that assist efficient harvesting of the rainwater, while the ‘Honeycomb’ storage systems keep this water fresh and algae free for up to seven years.
These, and other such innovative market offerings, are adding a compelling commercial argument to rainwater harvesting, which could mainstream the solution in the very near future.
An Intuitive And Scalable Solution
Perhaps the single greatest strength of rainwater harvesting is that it can be implemented at any scale from a single home to a community, or even at a city or national grid scale. However, despite how intuitive the solution is, it does have its challenges. Water held in underground tanks for an extended period of time becomes stale and is often contaminated by pathogens. Keeping this stored water fresh requires constant aeration or chemical additives — sometimes both — for it to remain potable.
Nevertheless, the additional energy used for aeration can easily be offset by the fact that this model eliminates the energy required for water to be pumped over long distances until it gets to the end user. Emerging technologies, from breathable surfaces created by coated sand to microbial fuel cells, will soon make it possible to keep stored water fresh for extended periods sustainably.
An unprecedented human population is stretching our capacity to support it, with the future looking even more challenging. We anticipate that in just a few decades, water security for large urban populations will require the creation of multiple rainwater harvesting structures, both distributed and interconnected.