California’s ambitious plan to convert its vast network of irrigation canals into solar power systems has the potential to reshape both the state’s water management strategy and its renewable-energy landscape. By installing solar panels directly above open-air canals, researchers estimate that the state could generate up to 13 gigawatts (GW) of clean electricity while simultaneously saving approximately 63 billion gallons of water each year. These figures are based on modeling from a collaborative study by UC Merced and Solar AquaGrid, which highlights the dramatic dual benefit of conserving water and producing renewable energy.
(Source: UC Merced & Solar AquaGrid – “The California Solar Canal Project,” 2021; Nature Sustainability.)

But the impact of canal-top solar installations goes far beyond energy production. One of California’s biggest environmental challenges is extreme water loss from evaporation, especially during long, dry summers intensified by climate change. Shading the canals with photovoltaic panels helps keep the flowing water cooler, significantly reducing evaporation rates. This is particularly important for a state that relies heavily on its interconnected water-delivery system to support agriculture, cities, and ecosystems.
(Source: California Department of Water Resources; NASA Climate Data.)

The strategy also offers a rare “two-in-one” climate solution: the panels generate renewable power at scale while simultaneously protecting a critical water resource. Because solar panels operate more efficiently at lower temperatures, the natural cooling effect of water beneath them enhances their energy output compared to panels installed on hot, dry land. This cooling-boosted efficiency has been demonstrated in similar projects in India’s Gujarat region, which pioneered the canal-top solar concept nearly a decade ago.
(Source: International Journal of Renewable Energy; India’s Gujarat Energy Research and Management Institute.)

Beyond performance gains, canal-top solar helps reduce operational and maintenance costs. Unshaded canals often face algae growth, weed intrusion, and temperature fluctuations that degrade water quality and restrict flow rates. By covering these canals, municipalities can slow biological growth and reduce the labor required to manage vegetation and debris. This translates into long-term savings and improved efficiency across California’s water-delivery infrastructure.
(Source: California State Water Resources Control Board.)

Another advantage is that the system avoids common land-use conflicts associated with large ground-mounted solar farms. In many regions, solar installations compete with agricultural land, wildlife habitats, or community development. California’s canal system offers thousands of miles of existing infrastructure—nearly 4,000 miles statewide—that can support solar arrays without displacing farmland or natural ecosystems. Even partial coverage could supply electricity to millions of homes, underscoring the vast scalability of the approach.
(Source: U.S. Bureau of Reclamation; U.S. Department of Energy.)

The initiative is currently being tested through Project Nexus, a pilot program launched by the Turlock Irrigation District (TID) in partnership with UC Merced, Solar AquaGrid, and the California Department of Water Resources. The pilot aims to measure long-term energy yield, durability, evaporation reduction, and overall cost-effectiveness. Results from Project Nexus will guide statewide decisions and could influence national policy on water-energy management.
(Source: TID Press Release; California DWR.)

If successful, California’s model could extend to other drought-prone states such as Arizona, Nevada, and Texas—regions where water scarcity and high solar potential intersect. With climate change intensifying drought cycles across the American West, this approach offers a promising blueprint for future-focused infrastructure that supports both environmental resilience and clean-energy expansion.

In essence, California’s solar-canal initiative is more than just an upgrade to traditional solar power deployment. It represents a bold rethinking of how infrastructure can serve multiple climate-critical functions at once. By integrating energy production, water conservation, and modernization of public utilities, the project could signal a transformative shift in the way the United States manages essential resources in a warming world.