See how solar power can solve the problem of water scarcity in India

Fri, 2018-06-15 11:32 -- SCC India Staff

Solar power

When we imagine the possibilities for solar power, we might well see it as the bedrock of a future 100 per cent renewables-powered grid - harnessing the abundance of energy beamed down on us daily, to give 100 per cent reliability of supply and enabling prices to be a tenth of what they are today. We are a tropical country blessed with ample sunshine even during the monsoon months. Yet despite all our plentiful rainfall, we still suffer from severe water scarcity.

The current government is making a compelling push for renewables and explicitly wants to transition us to a ‘Solar Nation’. In no small part to reduce the national import bill as we still source much of our energy externally, notably in the form of oil and coal. But also, because national energy-independence could accelerate the Make in India campaign by providing the cheapest possible power. Of all the possibilities we can then consider, the most fundamental development and national health challenge in need of addressing is our extreme water distress.

A recent World Economic Forum report ranked water scarcity as the top global concern over the coming decades. By some estimates, in India near 160 million people lack access to clean water – the highest of any country in the world. This is compounded by the agricultural sector having the highest water use – over 60 per cent of consumption – meaning that water shortages will also pose a dire threat to national food security. With domestic reservoirs shrinking, water taps could quite feasibly go completely dry. So, it’s not much of stretch to say that India is sitting on a ticking time bomb.

Water management must be both economical and equitable, and presently it is neither. Overutilization of water resources, through diminishing the water table, is leading to very high inequality and misallocation - only those who can afford pumps get clean water, whilst those most in need remain water impoverished. There are two strands to addressing this challenge. Pumping for distribution, and desalinization or water purification, depending on the part of the country being considered. These are parallel needs, each highly energy intensive, so in turn highly expensive.

The effective harnessing of solar power can address both. In the first instance, cheap solar power will allow unconstrained pumping of clean water across immense distances. In the second instance, nascent desalination technologies - such as reverse osmosis - that are currently hamstrung by huge scaling costs, can then take off. Solar power can in effect offer the possibility of a ‘water grid’, enabling far better water management. In the near term, pumping could be done from places where there is good groundwater availability, and ample surface water seasonally. Similarly, rainwater could be harvested from places which were previously unviable and transported to alleviate scarcity elsewhere. In these cases, the water table can then be managed more effectively.

A key future use-case will be for sea-water desalinization plants built along the coast, or possibly at some suitable inland locations, such as Sambhar lake in Rajasthan. Along with abundant sunshine, India is fortunately also blessed with vast ocean access. But the building of this new national-scale infrastructure will be substantial, with massive energy demands to fully service the country. For a large-scale desalination plant, up to 40 percent of its operating cost can go towards power. Solar can thus facilitate this through significantly lower costs, and the pumping of clean water to the central and northern inlands, and even onwards to other countries in similar need.

At the other end of the scale, increased distributed energy offers far wider possibilities for water purification. For example, solar microgrid-powered technologies, that can filter and convert local unpotable water into clean drinkable water. Again, currently scaling is a big challenge, as there is a significant difference between even a small and medium-sized rural village. We have little idea what this will look like geographically in the future, but it is not a stretch to imagine the flexibility solar-power could afford.

So, water security will require us to have vast amounts of cheap power, which can be provided by Solar. However, as with all renewables, this is highly weather dependent and inherently variable, so will increase grid-volatility, which seems like just trading one problem for another. Already today, even with just a small penetration of renewable generation, the intermittency has caused a significant rise in grid balancing costs, and in the future this could be huge. Further, integrating renewable energy and water into a unified infrastructure is taking two already highly complex systems, and making them significantly more so - a double whammy of complexity and volatility.

It is already difficult for us to manage the complexity of each today, with the increased grid volatility due renewables pointing to further challenges for integrating the energy and water systems. So, given this, to realize the vision we must find one additional solution component. A way to address this challenge, which will analyse real-time data across the combined energy and water ecosystem, for optimal management and benefit-to-cost ratio.

This is where Artificial Intelligence and Machine Learning (AI and ML) based software can be that final common jigsaw piece. To crunch the exponential volumes of data required to manage this complexity, balance gird-volatility, forecast future trends, optimise water pumping and desalinization assets, run power and purification plants, and plan future infrastructure. Only AI combined with modern raw computational power, can provide the necessary operational and consumption optimisation to keep this whole multifaceted water-grid running smoothly 24/7. By figuring out where and how best to balance variable power and water demands across the entire country.

In a solar power and clean water future, AI software can manage key aspects of the joint ecosystem, to achieve optimal levels of decision making. Together these have the potential to help India realize the vision of national water security and affordable clean water access for all its people. Thus, enabling this looming demon to finally be defeated and dispelled.