By Holbert Janson
Nexus: Noun; A connection, link, or tie.
If you haven’t yet heard the term, you will likely feel the impact of the water-energy nexus at some point in the near future.
Simply put, there is a critical link between our finite energy resources and our finite water resources. Creating energy is a water-intensive undertaking. Likewise, managing our water needs requires a huge amount of energy. What makes this noteworthy is the fact that many parts of the world, including the U.S., are dealing with shortages in both of these resources.
Managing the two is going to be a global challenge for the next several decades. Many parts of the world, including Texas and the UK, are dealing with current and pending energy shortages. Addressing these shortages is a multifaceted challenge. The fix will require equal parts technology, policy, environmental protection, and fresh water management.
In order to generate more energy, more fresh water is required. Currently the cheapest means of generating electricity on a large scale is by the burning of fossil fuels, particularly coal and natural gas. These also happen to be among the most water-intensive methods of generating electricity.
Wind and solar are among the least water-intensive ways of generating electricity. The problem with these methods is that they are not cost effective with current technology. Both require either subsidies or government mandates in order to compete.
Water plays an important role in just about every stage of the production of energy. For example, the current preferred method for extraction of natural gas from the ground is called hydraulic fracturing – more commonly known as fracking. This method involves pumping massive amounts of water into the ground to break up underground rock formations.
At the point where energy is produced, there is also a large need for water for most types of power plants. Aside from the obvious example of hydroelectric power which uses water directly to produce electricity; water is a critical cooling component for nuclear power plants and fossil fuel-burning power plants.
In drought-stricken Texas where electricity is badly needed, plans for some power plants have been stalled because of a lack of fresh water that is needed to run the plants. Although Texas leads the nation (and much of the world) in the production of wind energy, most Texas electricity still comes from coal or natural gas-burning plants. These plants need water to cool their systems. That means plants need to be built within reach of large fresh water sources, and they must have the permission and permits to access that water.
Most of this water is eventually discharged back to the source, but a significant portion of it is turned to steam and released into the atmosphere; meaning it is lost to the local environment. This has led to a push for better cooling technology for power plants to mitigate water loss.
The link between water and energy means that policy makers at every level must integrate their energy and water policies. This need to harmonize water and energy policies has brought together the American Council for an Energy-Efficient Economy (ACEEE) and the Alliance for Water Efficiency (AWE) to collaborate on ways to steer policy at all levels toward optimal solutions for solving energy problems without exacerbating water problems and vice versa.
Did you know?
- Worldwide, more water is used in the production of energy than for irrigation.
- Nuclear power plants consume the most water per power plant.
- Coal power plants require large amounts of fresh water to cool their systems.
- China and India have plans to build over $700 billion worth of coal power plants over the next 20 years.
- Thirty-nine percent of all freshwater withdrawals in the United States are to support electricity production from fossil fuels and nuclear energy. This equates to 190 billion gallons of water per day.
- Energy production in the United States accounts for over half of the water withdrawn from lakes and rivers each day.
- The energy sector is expected to account for 85 percent of the growth in U.S. water demand over the next 20 years.