Solar energy is a key component of the strategy to meet global climate goals. As technologies improve and costs decrease, we can expect continued, rapid solar development. But land is a finite resource, and utility solar energy requires a sizable land footprint. Nevertheless, there are options to reduce its land-intensity. In this piece, we examine solar’s true footprint and outline some of the less land intensive options for farming the sun.
Solar’s opponents claim that photovoltaics are a land-hungry endeavor that will eat up open spaces and rob us of agricultural roots before even scratching the surface of our energy needs. But let’s look at the facts: by conservative estimates, it would take around 22,000 square miles (sq mi)—less than the land area of West Virginia— to power the entire United States with solar. As new, more efficient technologies come online, this number could rapidly shrink to 10,000 sq mi or less—similar to the area of Maryland.
Globally, researchers assert that land availability should not prove to be a problem, even in a solar-centered international market. Current electricity consumption could be met by PV covering 0.3 percent of global land area. We should not constrain ourselves, however, to standard, utility-scale installations. The future of solar should deploy all options available, including floating PVs (“floatovoltaics”), agrivoltaics vertical PV, and building integrated arrays. Let’s take a closer look at these options.
Solar panels require space, but that need not be on land. Floating solar, also known as “floatovoltaics” or floating solar photovoltaics (FSPVs), are PV modules sited on bodies of water. Panels may be mounted on pontoons, polymer floats, or thin, flexible membranes. The National Renewable Energy Laboratory (NREL) estimates that FSPVs could divert panels from more than 8,100 sq mi of land; installations on one quarter of man-made U.S. reservoirs could produce around 10 percent of the country’s current power generation. Floating panels tend to operate more efficiently and are up to 22 percent more productive as water cools the equipment. They also provide environmental and water use benefits by preventing evaporation and overgrowth of algal blooms.
California became host to the world’s first large-scale FSPV system in 2011, and since then installations have spread across the globe. In 2022, the U.S. Army deployed a one megawatt floatovoltaic array at Fort Liberty in North Carolina as part of its resilience and security strategy. Currently, FSPVs make up only two percent of U.S. solar installations, and projects tend to be more costly than land-based solar. But development is now accelerating, and will only continue to grow as innovation drives costs down. The floatovoltaics market is projected to surpass $10.09 billion by 2030, up from $2.55 billion in 2021.
A few months ago, we published a piece detailing the mutually beneficial partnership between agriculture and solar. While many fear that solar farms will steal and damage valuable agricultural acreage, studies show that properly-managed solar farms will not negatively impact host land. What’s more, co-locating crops and PVs can alleviate land use concerns while increasing both agricultural and solar energy productivity. For more information on the benefits of agrivoltaics and important project considerations, check out our article here.
Upright solar systems are another emerging option to alleviate land use concerns. Vertical, bifacial solar panels consume minimal ground space and can be deployed alongside farmland, railroads, highways, parking lots, fences, or residential areas. Alongside agriculture, upright panels may serve as windbreaker “fences” and help increase yield; others have proposed use as sound barriers along noisy corridors. Recent studies have suggested similar or even improved productivity over traditional, south-facing panels when lined facing east-west. While this technology is currently more expensive than traditional PV systems, proponents argue that vertical panels costs offer electricity for extended periods of time. In addition, costs will likely decrease in line with technological improvements.
Building Integrated Photovoltaics
Building integrated photovoltaics (BIPV) serve as both structural building components like roofs, facades, and windows and as means of generating electricity for on-site or grid use. These technologies—such as thin films, crystalline panels, or solar shingles—may be inserted at the time of initial design and construction or added to existing buildings via retrofit. These options are initially more expensive than traditional building materials, but may provide significant cost savings over time and contribute to energy security and independence. The BIPV market is expected to grow at a 22.8 percent compound annual growth rate in the coming years, reaching a $99.7 billion market valuation by 2031.
A Bright Future
In the face of land use and permitting concerns, there are actually a multitude of innovative options to drive us toward a bright solar future. Leyline looks forward to seeing what is next for these exciting technologies.