Over the past several weeks, I've written a lot about the intimate and inextricable connection between energy and water. The energy-water nexus involves a number of technologies, environmental factors and stakeholders. Thus, it’s no surprise that water and energy’s fundamental connection has eluded policymakers for so long. With this post, I review the lessons discussed so far, so that policymakers can understand the key issues surrounding the energy-water nexus and what’s at stake if we fail to act now.
The Bottom Line
Conventional electricity sources, like coal, natural gas and nuclear power plants, require an abundance of water — about 190 billion gallons per day. Because the majority of our electricity comes from these sources, high energy use strains the water system and contributes to Texas’ prolonged drought. Coincidentally, extreme drought could force power plants to shut down.
Climate change is having a profound effect on our weather patterns, making extreme heat and drought more common in Texas and throughout the Southwest. If we don’t set the energy-water system on a sustainable course, we risk a compounded problem.
Finding a solution will require unconventional cooperation and swift action.
To reduce the water footprint of our energy sources, the water consumption of electricity sources should be an integral part of long-term electricity planning, and be reflected in competitive electricity markets.
Today, the lower water impact of wind and solar facilities versus a coal plant is not accounted for in the energy market or by most electricity planners. Renewable energy sources, such as wind and solar photovoltaics, use essentially no water, giving them a vast advantage over fossil-fuel electricity sources. Integrating water use with electricity planning and the wholesale electricity market would help reveal synergies that show just how competitive renewables are with fossil fuels, and speed our transition to a clean energy economy.
Energy efficiency upgrades and reductions in energy use through demand response are some of the most cost-effective energy resources we have. These innovative technologies reduce Texas’ reliance on fossil-fuel electricity and actually bolster our water supply and cut harmful carbon emissions at the same time. Accounting for water use would go a long way towards integrating these unconventional “negawatt” energy resources (technologies that save energy through efficiency) into the power market.
The more we include water and other environmental considerations in the energy market—the faster we can transition to a cleaner, more sustainable energy system.
Of course, it’s a two-way street. The energy and greenhouse gas (GHG) emissions impact of the water system should be a major part of water planning. When water planners consider energy use, they discover unique opportunities to cut energy costs and reduce emissions.
Mirroring the case for energy, water conservation is the best way to preserve our water supply and reduce the energy required for water operations. Simple strategies, such as using reclaimed wastewater for irrigation, can vastly reduce a city’s water needs. State and municipal planners should always weigh the benefits of water conservation initiatives versus building a new energy-intensive water treatment plant or pipeline.
It’s all connected. Conserving energy saves water and conserving water saves energy.
If we break down the longstanding division between energy and water planning, we reveal the most beneficial steps to improve the efficiency of the energy-water system.
San Antonio: A Model for Energy-Water Co-Management
The city of San Antonio offers a good example of effective energy-water co-management. San Antonio Water System (SAWS) prioritizes energy management and has won numerous awards for its energy savings. The water utility’s most innovative project to date is Dos Rios, a combined sewage treatment and biogas plant that reduces harmful air pollution and generates revenue from the sale of biogas. CPS Energy, the city’s municipally-owned electric utility, even installed a 20 megawatt solar farm at the facility to further cut down GHG emissions and water-use.
San Antonio is a unique case: it has the jurisdictional advantage of local control over both its electricity and water. The city maintains control of its electric utility due to an exception for municipal utilities in Texas’ 1999 electricity deregulation bill, and water utilities remain under municipal control throughout the state. CPS Energy and SAWS recognize each other as among their largest customers, and coordinate their planning cycles accordingly.
The city also benefits from a uniquely water-smart population. Until recently, San Antonio received all its water from one source, the Edwards Aquifer. Because the aquifer is a vital water source for a large portion of South-Central Texas, San Antonio residents were raised with water conservation in mind to preserve the aquifer.
The unique factors contributing to San Antonio’s leadership in energy-water co-management can’t be seamlessly transplanted into other cities and counties. The regulatory division between electric and water utilities is complex and varies from state to state. Nevertheless, San Antonio embodies the best practices that could be adopted and applied to many cities’ unique energy-water challenges.
Facing the energy-water nexus head on will take a monumental effort from the highest levels of government. We’re just now realizing the profound connection between energy and water use —but the energy-water nexus will be with us for some time. Climate change is accelerating, and we can expect drought to become more common in the future.
We have to emphasize energy and water co-management as the nation’s energy system slowly evolves and prioritize low-water and low-carbon options like wind and solar. Leaders at the local, state, national and international levels should bridge the divide between energy and water as they develop solutions to transform the global energy system and cope with a changing climate.
This is one of a group of posts that examines the energy-water nexus, Texas’ current approach to energy and water policy and what Texans can learn from other places to better manage its vital resources.