T Pradeep

IIT, Chennai

T Pradeep

Session 1D: Symposium on “The International Year of Basic Sciences for Sustainable Development”

Water: Gaps and opportunities

Abstract: Water is both local and global, just as carbon dioxide. However, while number of water molecules on the planet is roughly constant at 33.4x1045, total CO2 continues to rise. India has just 4% of the global freshwater resources but ∼18% of the world’s population. The country, which was largely rural years ago, has en-masse become urban in the past two decades. With a growth rate over 6% in gross domestic product (GDP), the most populous countries, such as India and China, are increasing their chemical, pharmaceutical, agrochemical, automotive, petrochemical, semiconductor, and many other outputs, which will eventually “enrich” our ecosystem materially. Simultaneously, their rapidly declining water resources will be burdened by unprocessed industrial waste. The World Bank has predicted that achieving a growth rate of 8% or above for India will be possible only with a robust water management system. These emerging issues, like those existing throughout the world, present a complicated suite of problems that will require technological advances, limits on usage, and collective wisdom, and compassion to create sustainable solutions. For instance, the control over carbon emissions by developed countries is probably not the reason for the globe’s survival, but the lack of development in less-developed countries according to the Intergovernmental Panel on Climate Change (IPCC). Sustainable economic and technological development for all is needed, although acquiring a quality of life comparable to the United States for the rest of the world would require significant advances in treating, purifying, and managing water.

Water footprint, estimated by considering production and consumption of goods and services, works out to 2842, 1071 and 1089 m3 per capita per year (PCPY), respectively for USA, China and India, the global average being 1385 PCPY. Therefore, with a water availability of around 1100 m3 PCPY, India has no water to lose and no water to dirty during diverse activities. Besides, the country experiences extremes such as ambient temperatures in the range of -40 to +50oC and rainfall between 210 to 11800 mm, making every possible water technology as necessary. Where do we look for new innovations to address water challenges? Let us look at two suggestions: (1) Make desalination Net Zero. Global CO2 emissions due to desalination were nearly 76 million tons (MT) in 2015, and global methanol requirements in that year were approximately 75 MT. Can an efficient catalytic system make CO2-to-methanol conversion possible with renewable energy so that India contributes to Net Zero as far as desalination is concerned (and subsequently in other sectors)? (2) Implement water audit on every product. We need to count the water cost from food to toiletries. For example, cradle-to-grave life cycle assessments of the process of washing 5 kg of laundry (requiring medium hardness water at 40oC and consuming 120 g of liquid detergent, 49 L of water, and 0.53 kWh of electricity per washing cycle) reveals a primary energy footprint of 6.57 MJ equivalent and a carbon footprint of 0.54 kg CO2 equivalent. This understanding may change the consumer’s choice of detergents, packaging materials, chemicals, building materials, clothing, etc., and consequently lead to new products which are less harmful to the environment, while being affordable. This thought would extend to create new agriculture, clothing, infrastructure, transportation, etc. We may move to more efficient irrigation, ‘water smart’ foodstuff, which will also be animal friendly. Water for all sustainably calls for radically new innovations.

It is clear that water is big in every scale–Gaps, opportunities, wealth and ultimately professional satisfaction.