Water is going to be a high precious product for next century which can match with the rank of what today hydrocarbon products mean to most people across the world. It is going to be a scarce and rare commodity as it rules life.
Water is an integral part of energy development, production, and generation. Water is used directly in hydroelectric power generation and is used extensively for thermoelectric power plant cooling and air emissions control.
Water is also used extensively in energy-resource extraction, refining, and processing, as well as for energy resource transportation.
The World Economic Forum (WEF) published a report in early 2009 highlighting that water use by the energy sector in developed countries averages about 40 per cent of total water use.
Therefore, as global energy consumption continues to increase, as much as 50 per cent by 2030, this growth will place the energy sector into greater competition with other major water users and exacerbate concerns about how to balance water use for domestic supplies, food production, and energy production with public health and economic development.
Unfortunately, this large growth in energy development and the expected increasing water use are occurring at a time when freshwater availability is already being stressed in many regions of the world, including many regions of the United States.
This is due to changing precipitation patterns, increased ecological and environmental concerns and demands for water, and unsustainable surface water and groundwater withdrawal and use.
Therefore, as nations try to balance the demands and availability of water resources to support human health and economic development in the coming decades, it is clear that: the water footprint, like the carbon footprint, will become an increasingly critical factor to consider in addressing reliable and sustainable energy development worldwide.
These issues of the growing interdependencies between the energy and water sectors was first highlighted in a report to Congress prepared in 2007 by Sandia and Los Alamos National Laboratories in cooperation with the National Energy Technology Laboratory and the Electric Power Research Institute (EPRI).
Since then, concerns over water availability and impacts on future energy development have been recognized by energy and water managers worldwide.
The World Economic Forum, the World Business Council on Sustainable Development, and the World Energy Council (WEC) have all published reports outlining the emerging energy and water concerns and the potential impacts on economic growth.
WEC’s September 2010 report on ”Water for Energy,” for example, identifies several regions of the globe where water supply availability is currently insufficient to meet proposed energy development.
Of increasing concern is that the emerging energy strategies of many countries, increased use of biofuels, shale oils, oil sands, coal-to-liquids, carbon capture and sequestration, and gas shales, all have water needs well above those of more traditional energy resources.
The corollary to the above discussion is that the water sector is very energy-intensive, and like the energy sector, the trend for new water and wastewater treatment technologies to meet increasing stringent water quality issues, are much more energy-intensive.
The water and waste sector is typically identified as using about 3 per cent of total US electric power demand. This ranks it as one of the larger electric power use sectors in the United States.
Recent research though has identified that the water system, end-to-end, is responsible for more than 12 per cent of national energy consumption.
That energy is used for conveyance, treating, distributing, heating, pressurizing, chilling and remediating water.
As we exploit poorer-quality water sources-seawater, saline groundwater, and industrial and domestic wastewater-to meet future water demands, the associated energy demands will grow.
For example, wastewater reuse in the United States is growing at 15 per cent a year and desalination is growing at 10 per cent per year, and these two water supplies currently require two to five times more energy per unit of water produced than traditional water treatment technologies.
On the wastewater side, many current water disinfection approaches, such as chlorination, do not use much energy but are being replaced by very high energy use ultraviolet (UV) systems to reduce the formation of harmful disinfection by-products.
And the move to treat and reduce contaminant levels to the part per billion or part per trillion ranges means that sophisticated high energy demand water treatment technologies could likely be required.
To help develop a dialogue on how to address these growing concerns, many agencies have studied ways to reduce these emerging impacts.
For example, Sandia conducted a study in 2007, and other groups like the National Science Foundation, General Accountability Office, National Research Council, Electric Power Research Institute, Department of Energy, and Johnson Foundation have also recently evaluated approaches and research needed to address these concerns. Most ideas fall into three major categories:
Reduce water use for electric power and transportation fuels.
Many approaches exist that could help reduce water consumption for electric power generation, but technologies like dry and hybrid cooling and renewable energy have cost or intermittency issues that must be improved.
Since virtually all new alternative transportation fuels will increase freshwater consumption, major scale-up of these fuels must include approaches that use less water for growing, mining, processing, or refining.
Develop materials and water treatment technologies that more easily enable use of non-traditional water resources.
With freshwater supplies becoming more limited, wastewater reuse and non-traditional water use, including sea water, brackish ground water, and produced water will be needed.
New water treatment technologies that can meet emerging water quality requirements at much lower energy use will be important.
These improvements could reduce energy use for water treatment and pumping, while accelerating the use of non-traditional water resources in the energy sector, such as for cooling or for hydraulic fracking. Improve water assessment and energy and water systems analysis and decision tools.
Compounding the uncertainty of available water supplies is a lack of data on water consumption.
Improved water use and consumption data collection and better water monitoring are needed.
Improved decision support tools and system analysis approaches are also needed to help communities and regions better understand and collaborate to sustainably develop solutions that minimize freshwater demand and consumption.
From the private sector, companies and associations have already started to leverage their talent and resources to address these issues.
For example, EPRI and their power utility affiliates have initiated studies of new low-water use cooling approaches and have helped develop a $16 million large-scale testing facility at a power plant in the southeastern United States to test innovative, low water use cooling technologies.
In the oil and gas area, companies in both Canada and the United States have implemented approaches to use brackish water and water reuse in oil sands and hydraulic fracturing to minimize both the use of freshwater and wastewater disposal.
These efforts all support the broader focus of addressing a more balanced and sustainable use of natural and financial resources to support public health and economic development.
(The author advises US government on projects for future challenges.)