Globally, demand for food, water, and energy is rising sharply. The World Economic Forum says that by 2050, demand for food could grow by more than 50%, energy by up to 19%, and water by up to 30%. The increasing scarcity of these resources—and the potential solutions for managing them sustainably—are closely interconnected, calling for integrated approaches.
The World Economic Forum wrote in a report released last July: “Any disruption in one of these resources reinforces vulnerabilities and trade-offs in the others. Such disruptions also create opportunities for sustainable growth, greater resilience, and more equity.” The idea of synergistic solutions within this nexus has been gaining momentum in both the public and private sectors.
One example is a new initiative in California called Project Nexus, which seeks to put this nexus into practice. The innovative project aims to integrate water management and renewable energy production in some of the sunniest and most water-stressed farmland in the United States by covering miles of irrigation canals with solar panels, producing multiple benefits within the water–energy–food framework.
While the panels generate clean energy, they also shade the canals from harsh desert sun, reducing water losses from evaporation and limiting aquatic weed growth that could choke waterways. In addition, the water beneath the panels serves as a natural cooling system. According to a report by SFGATE, this $20 million state-funded initiative could generate up to 1.6 megawatts of renewable power “along with a host of other benefits.”
Beyond these advantages, placing solar panels above existing agricultural infrastructure could provide key benefits compared with traditional solar farms. They can be adopted more quickly and easily because they avoid land-use conflicts, which have become a major obstacle for utility-scale solar projects across the U.S. “Putting solar panels on existing infrastructure does not require altering the landscape, and these relatively small installations can connect to nearby distribution lines, avoiding the complex process of tying into high-voltage transmission needed for large projects,” according to Canary Media.
The outcome of Project Nexus and similar models appears to be a triple win for water, energy, and food, all while using less land. Project scientist Brandi McKuin said: “The challenges of climate change will force us to do more with far fewer resources… so this is just an example of the kind of infrastructure that can make us more resilient.” She added that the project will not release final figures until after a full year of operation, but current analysis shows performance is on track to meet its goals.
Project Nexus is not the first to install solar panels over canals, but it remains among the few such projects worldwide. The U.S. launched its first and only project of this kind in Arizona late last year, generating power for the Pima and Maricopa tribes, together known as the Gila River Indian Community. While many large-scale renewable energy projects have faced land-use disputes tied to tribal lands, the Arizona project demonstrates that the canal model can be an excellent alternative.
David DeJong, director of the Pima-Maricopa irrigation project, told Grist: “Why disrupt sacred lands when we can simply put solar panels over a canal and generate more efficient power?” In line with the spirit of synergistic water–energy solutions, the project is also working on a system to deliver water to the Gila River Indian Community, which faces water scarcity.
Of course, these pilot projects generate far less power than utility-scale solar farms. But research suggests that if the solar canal concept were expanded to cover 8,000 miles of federally owned canals and waterways in the U.S., the impact could be significant. In 2023, a coalition of environmental organizations estimated that installing panels on all such existing infrastructure could generate more than 25 gigawatts of power while preventing the evaporation of tens of billions of gallons of water.
