The cost of solar technology has come down, way down, making it is a viable way to expand access to energy for hundreds of millions of people living in energy poverty. For farmers in developing countries, the growing availability of solar water pumps offers a viable alternative to system dependent on fossil fuel or grid electricity. While relatively limited, experience in several countries shows how solar irrigation pumps can make farmers more resilient against the erratic shifts in rainfall patterns caused by climate change or the unreliable supply and high costs of fossil fuels needed to operate water pumps. Experience also suggests a number of creative ways that potential water resource trade-offs can be addressed.
Water security is a major challenge for many countries, especially developing ones. The numbers tell a story of water resources under stress while competition for their use is increasing – by 2025, about 1.8 billion people will be living in regions or countries with absolute water scarcity. Clean water and adequate sanitation is still far from reach for many of the world’s poorest. At the same time, more water is needed to produce food and energy to satisfy the rising needs of the earth’s growing population.
Each year on March 22 we mark World Water Day. It is an opportunity to keep the urgent water issues – from lack of sanitation to transboundary water to climate change -- top of my mind for practitioners, decision makers and the global public. In the coming days we will post here updates and stories from the field, as well as links to some of our partners’ content. But, more importantly, this is an opportunity to hear from you, too.
The theme of this year’s #worldwaterday focuses on water and energy. And for good reasons.
For the last six years, a power plant in San Luis Potosi, Mexico has bought water from a nearby wastewater treatment plant to use in its cooling towers (instead of using freshwater). This operation, Project Tenorio, a public-private partnership, continues today and has already resulted in the reduction of groundwater extraction of at least 48 million cubic meters (equivalent to 19,000 Olympic size pools) and increased aquifer sustainability.
This is a good example of the water and energy nexus in practice: the wastewater treatment plant covers almost all of its operating costs from this additional revenue stream and the power plant gets a more reliable water source that is also 33% cheaper than groundwater in that area.
Treated wastewater has been used to reduce the water requirements of power plants in several other countries as well, as water supply becomes more variable or disappears. In the US, for example, around 50 power plants are using treated wastewater for cooling in order to adapt to water shortages. However, innovative integrated approaches like these are still more of an exception than the norm.
After an intense and exciting week in Stockholm for World Water Week, it is time to look back at some conclusions of the conference and the way forward for next year. I was in Stockholm as a “Lead Rapporteur” and reported in the closing plenary session on “Cooperation to achieve equity by balancing competing demands”; other teams reported on “Managing waters across borders,” “Responding to Global Change,” and “Closing the science-policy-practice loop” (see closing plenary here). This is my attempt to summarize over 100 sessions, you can find all the sessions in the WWW website.
Next week as thousands of practitioners gather at annual World Water Week in Sweden the focus is on cooperation, echoing the UN’s declaration of 2013 as the International Year of Water Cooperation.