The post is in continuation with couple of discussions i had recently with some passionate practitioners of Sustainability.
The discussion started at a talk on sustainability . Post my talk, a few students wanted to know more about why i think water and energy have to be discussed in parallel and how do these fit in the overall context of Climate Change and sustainability.
Though i could give convincing answers to the students, i thought, i must write something to be able to myself appreciate the idea better. Hence this post.
Energy – Water Nexus
As Population increase, demands for water and energy threaten to push the limits of what our environment can sustain. Another compelling reason to pay cognisance to the water-energy nexus is climate change, which may result in significant alterations to precipitation patterns with all that implies for altered water availability and the power derived from water.
“The Energy problem is actually a water problem”. Water and energy also affect food security and hence there is Water -Energy – Food Nexus.
United Nations Water asserts in the World Water Development report 2014, ” Water , Energy and food are inextricably linked….The global community is well aware of food, energy and water challenges , but has so far addressed them in isolation,” There are many synergies and trade-offs between water and energy use and food production. Here are some examples from the report ;
Using water to irrigate crops can promote food production but it also reduce river flows and hydropower potential.
Growing bioenergy crops under irrigated agriculture can increase overall water withdrawals and jeopardize food security.
Converting surface irrigation into high-efficiency pressurized irrigation may save water but may result in higher energy use.
Recognizing these synergies and balancing these trade-offs is central to jointly ensuring water,energy and food security.
The world Business Council for Sustainable Development (WBCSD) notes on its portal ,”There is an intrinsic link between the challenge we face to ensure water security and other global issues, most notably climate change and the need to sustainably manage the world’s rapidly growing demand for energy and food.
Humanity needs to feed more people with less water , in a context of Climate Change and growing energy demand, while maintaining healthy ecosystems. ”
The FAO outlines the global challenge posed by the nexus
The situation is expected to be exacerbated in the near future as 60% more food will need to be produced in order to feed the world population in 2050.
Global energy consumption is projected to grow by up to 50% by 2035
Total global water withdrawals for irrigation are projected to increase by 20 to 25% by 2050 (May be much more)(emphasis added).
Though this nexus is well appreciated , one of the paradigms of sustainability is to reduce the direct dependence of one on the other and loosen the nexus to the extent possible . For example rooftop solar energy does not put pressure on the land and does not divert the water from irrigation for running the plant. A kitchen composter does not use any external resource and makes compost for the plants.
The definition of sustainability must be the north star of a sustainability practitioner . For me this definition appealed the most ;
"The paradigm of development where progress is achieved in all spheres of life and in all segments of the society where resources (Natural, Social, Biological and economic) are used in a manner in which its quality and quantity is not compromised for the future generations."
Taking this argument ahead , a practitioner of sustainability must develop scalable and serviceable technologies and processes that are decentralized and hybrid and within the framework of the above definition .