Water and energy: A symbiotic relationship
February 08, 2023
February 08, 2023
Water and energy are critical to human life. They are intrinsically tied together, and innovation, demand, and limited resources affect both.
At the heart of our modern world are two central needs: Water and energy. Both are key to the well-being and prosperity of our people and our world. The United Nations recognises this by including the universal availability of sustainable water and sustainable energy as two of their Sustainable Development Goals. And they are both dependent on each other.
Water and energy have a symbiotic relationship. Water is used to produce energy, and energy is needed to produce and move water. The two are forever intertwined.
Whether it is the water consumed and used by people, the water that goes into producing food or the manufacturing of products, or the water required to produce power, two things are clear: Water needs energy and energy needs water. This is called the water-energy nexus and it’s critical in supporting human life on Earth.
Water is the building block of everyday life. From the water we use in our homes for drinking, showering, or cooking to the water needed for growing crops and producing food, it is a critical resource that humans rely on to survive. This water must be captured, treated, transported, and reused in the most efficient way possible to make it suitable for use when and where we need it.
It is here that we see the close relationship between water and energy. We must treat our water resources for communities to safely consume—but the treatment process requires an abundance of energy. For example, the California Department of Water Resources estimates that approximately 12% of the State’s energy use is related to water. And that figure is only likely to rise. The International Energy Agency (IEA) predicts that the energy used to power the water sector will double by 2040.
Another form of water treatment that is being used to combat the global water crisis is desalination. Desalination is the process that separates the salt from seawater, and it’s being used in areas that experience severe water shortages. Right now, over 2.3 billion people live in water-stressed countries. Desalination can provide clean drinking water for communities in need. However, the process requires a significant amount of energy. Some experts believe desalination results in too many harmful emissions to be a feasible option. But if we could power the process with clean energy sources, desalination could be more widely accepted.
Instead of consuming energy, recovering water for reuse—or wastewater treatment—could produce net energy. As mentioned above, treating and reusing as much water as possible is crucial in combating the global water crisis. But it’s also about recovering as much energy as possible. With wastewater treatment facilities, we have the opportunity to separate out organic materials and convert that material into biogas. We can directly use biogas to generate heat and electricity, and we can also further refine it into biomethane—or renewable natural gas (RNG).
As water becomes an even more limited natural resource in the future, the need to capture, clean, and reuse our water will only increase. Treating our drinking water, recovering our wastewater, and desalinating sea water can all help, but these all require energy.
Another key area where water and energy overlap is in power production. Hydroelectric power is a strong and obvious example. It generates clean renewable energy and is dependent solely on water without consuming it. But most forms of energy generation also need water. For example, a traditional thermal powerplant burns fuel—whether coal, oil, or natural gas—to boil water, create steam, and generate electricity. These types of power plants also require water for cooling purposes.
Another important form of energy will be hydrogen, especially green hydrogen—that is hydrogen produced using renewable energy. Hydrogen is the most abundant element in the universe and it releases no greenhouse gases (GHG) during combustion. That’s why experts believe it should be a part of the energy transition. But producing hydrogen requires a lot of water—conditioned water that must be treated before use. This water is put into an electrolyzer that splits water molecules into its two components: Hydrogen and oxygen. The hydrogen can then be used for heating, power, and industry.
Water and energy must work in lockstep as what impacts one directly impacts the other.
Another form of energy that is making strides is nuclear power. Traditionally, nuclear power has faced criticism for being costly, unsafe, or damaging to the environment. But recent advancements in small modular reactors have reinvigorated the industry. After all, if we are going to transition away from fossil fuels, we need a strong baseload energy capacity to replace them with. Nuclear could be that option. Nuclear plants use the process of fission to generate heat, create steam, and spin turbines to produce electricity. So, if we are to consider nuclear as part of our energy arsenal, water will be a key factor.
Most forms of energy production require water. And although solar power and wind power do not, the process of mining minerals and metals for the manufacturing of components for solar and wind technologies does. So, even forms of energy that don’t need water directly for generation require water at some point during their lifecycle.
Another key intersection for water and energy is in the industrial sector. We call this industrial water, and it is used for industrial practices when producing commodities, petrochemical products, mining materials, pharmaceuticals, and more. Food production also accounts for a significant amount of water use. Essentially, most of our everyday products require water to produce, and that requires a vast amount of energy.
One area of particular growth at the moment is the advanced manufacturing market. Recently in the US, grants and incentives have been offered to rebuild the US share of commercial semiconductor manufacturing. There are also grant opportunities for low- or zero-emission vehicle producers, transmission facilities, and GHG reductions technology.
According to the Environmental Protection Agency (EPA), the US uses more than 18 billion gallons of water per day for industrial purposes. These purposes can include fabricating, processing, heating, cooling, or transporting products. Extracting, using, treating, and rereleasing the water all must meet rigorous regulatory standards to ensure facilities are not damaging the environment—or our water supply.
Before manufacturers can rerelease water back into the environment, they need to make sure it is properly treated. That requires a large amount of energy, but it is necessary to safeguard communities as well as the environment. The water-energy nexus is still very much alive in the industrial sector.
The symbiotic relationship between water and energy is critical. This is especially true as we combat the global water crisis while pressing forward with the energy transition. Sometimes it feels like these two goals conflict with each other—and sometimes they do. But at the end of the day, we need water, we need energy, and we need to protect the planet for future generations.
We must work together if we hope to solve some the biggest challenges surrounding the water-energy nexus. To be successful, the water and energy industries must work in lockstep as what impacts one industry directly impacts the other. Our future depends on it.