Water and energy production have always been inextricably linked, but the amount of water needed to power our lives is increasing, according to the latest forecast from the International Energy Agency.
The role of water in energy, often referred to as the water-energy nexus, is getting more attention than ever before, and last month’s report from the IEA was the first time that the report has given water issues related to energy production its own section.
Energy production sucks up about 15 percent of the world’s total water withdrawal, which could increase by about 20 percent between 2010 and 2035. Much of the increase will be driven by higher-efficiency power plants and expanding biofuels production, according to the report.
“In an increasingly water-constrained world, the vulnerability of the energy sector to constraints in water availability can be expected to increase, as can issues around how the quality of water is affected by energy operations,” the IEA’s report stated.
The water-energy nexus will be a central focus at the inaugural International Water Summit, which is to be held during the Abu Dhabi Sustainability Week in January and hosted by Masdar. For the companies that provide energy infrastructure and the governments that regulate that infrastructure, now is the time to take an increasingly holistic approach wherein water and energy are seen not just as intersecting, but rather are recognized as two equal parts of the same whole.
A holistic approach means looking at every aspect of water use in energy. Sometimes, energy efficiency requires higher energy use, such as with some high efficiency power plant technologies, according to the International Energy Agency. In the U.S., water continues to be the second biggest concern of utilities.
But there are technologies that can vastly reduce carbon emissions and water at the same time. A new coal plant in South Africa, the Kusile project, will use 5 percent of the volume of water compared to a conventional new coal-fired power plant (thanks to dry cooling), according to Dean Oskvig, CEO of the energy division at Black & Veatch, a consultant and project manager for the Kusile power station.
Renewable energy sources, not including large-scale hydro, use far less water than fossil fuels and nuclear power. Butsolarand wind still make up a very small percentage of the overall energy picture, and coal continues to dominate in many regions, including the U.S., China and India. Retiring older coal power plants and limiting water-intensive biofuels are two of the most important changes that could stop the growth of water use in energy production. In areas of the U.S., some farmers are already competing with gas companies for water rights because of the significant requirements for hydraulic fracturing of shale gas wells.
It will not only be power producers that will need to think more critically about water -- water producers will need to think more seriously about energy, as well. In the U.S., for instance, drinking and wastewater systems account for up to 4 percent of the total energy use. That figure is expected to grow in the U.S. and worldwide as populations grow. More water-efficient irrigation also often involves more energy for pumps.
But systems-level thinking, which has been suggested as a method for improving electricity efficiency, can also apply to the water-energy nexus. There are a variety of technologies, both software and hardware, that can increase efficiencies in everything from energy production to agriculture.
Before water can be thought of as part of energy production, water itself needs to be thought of as a single sector, according to a contention in Black & Veatch’s first U.S. water utility industry survey. From 2005 to 2015, there will be a 25 percent increase in the use of treated wastewater or salt water in agriculture and aquaculture, according to the U.N.
“One water qualification that must be eliminated from the water industry vernacular is ‘waste’ water,” the report authors state. “It is time to shift our focus away from the elimination of something undesirable to the opportunity to recover valuable resources such as water, energy, nutrients and beneficial products.”