India's ambitious goal of producing five million metric tonnes of green hydrogen by 2030 has sparked conversations around funding, cost reduction, and production plans. However, amidst these discussions, an essential aspect remains largely overlooked—the crucial role of water supply. Green hydrogen, generated through electrolysis of water using renewable energy sources, holds immense potential for decarbonizing industries such as Iron and Steel, fertilizers, and Oil refineries, among others. Yet, the water requirement for green hydrogen production poses a significant challenge that demands attention and strategic planning. This article delves into the importance of water supply, its impact on green hydrogen production, and the need for sustainable solutions.
The Water Challenge in Green Hydrogen Production:
Water scarcity is a pressing concern in many parts of India, and the water demand-supply gap continues to widen. The International Energy Agency's report reveals that nine liters of water are necessary for every kilogram of green hydrogen produced. Access to freshwater in water-stressed areas becomes a critical hurdle in scaling up green hydrogen production. As the country embarks on its path towards a greener future, it must address the water-related implications to ensure sustainable and efficient production processes.
The choice of energy sources for electrolysis plays a significant role in determining the water requirements for green hydrogen production. When solar energy is utilized, the total water requirement, encompassing the energy source and electrolysis, is estimated to be around 32 kg of water per kg of green hydrogen. Alternatively, if wind energy is harnessed, the cumulative water requirement decreases to approximately 22 kg of water per kg of green hydrogen. Comparatively, the production of grey hydrogen using natural gas consumes 22 kg of water to generate just 1 kg of hydrogen (Source)
Recognizing the need for alternative water sources, the Ministry of New and Renewable Energy acknowledges the potential of municipal and industrial wastewater as feedstock for green hydrogen production (Source). However, the use of grey or saline water presents a challenge. Electrolysis processes require demineralized freshwater to achieve optimal performance. Jaideep Saraswat from Vasudha Foundation explains that impurities and mineral content in seawater or contaminated water reduce the efficiency and performance of electrolysis, hindering the overall effectiveness of green hydrogen production. Several states in India are grappling with water scarcity issues while endeavoring to meet their water demands.
As India strives to achieve its ambitious green hydrogen production targets, it must not overlook the crucial factor of water supply. The demand for green hydrogen necessitates significant volumes of water, highlighting the need for careful planning, efficient water management, and the exploration of alternative water sources. By addressing these challenges head-on and implementing sustainable solutions, India can unlock the potential of green hydrogen while mitigating the strain on water resources. It is imperative for the government, industries, and communities to collaborate and prioritize the integration of water sustainability into the green hydrogen roadmap, ensuring a harmonious and environmentally responsible transition to a hydrogen-based economy.