How much land would it take to get most of our electricity from solar and wind power?

Critics of wind and solar routinely raise concerns about how much land would be required to decarbonize the US power sector. Fortunately, the answer is relatively little. A recent National Renewable Energy Laboratory (NREL) study shows that it would take less than 1 percent of the land in the Lower 48 — that’s an area comparable to or even smaller than the fossil fuel industry’s current footprint. And when wind and solar projects are responsibly sited, the environmental and public health impacts would be far less harmful than those from extracting, producing, and burning fossil fuels.

A key role for wind and solar

The fact that renewables will not require an inordinate amount of land is welcome news because limiting climate change’s worst impacts will require us to cut global heat-trapping emissions roughly in half by 2030 and to achieve net-zero emissions by 2050, according to the Intergovernmental Panel on Climate Change (IPCC). Acknowledging that the United States is a leading contributor to carbon emissions, the Biden administration has committed to cutting US emissions 50 to 52 percent below 2005 levels by 2030. Most studies show that achieving these targets will require an unprecedented increase in wind and solar power to decarbonize the power sector and meet the increased demand for zero- carbon electricity to replace fossil fuels in building, industrial and transportation sectors.

A 2022 NREL study found that, to achieve President Biden’s goal of generating 80 percent zero-carbon electricity by 2030 and 100 percent by 2035, we will need to increase wind and solar power from about 14 percent of the US electricity mix in 2022 to between 60 and 75 percent by 2035 under the main scenarios. When combined with modest increases in geothermal and hydropower capacity at existing unpowered dams and upgrades to existing facilities, renewable energy would provide 70 to 85 percent of total US electricity generation by 2035. NREL projects that most of the remaining generation would come from existing nuclear plants and a small amount from gas plants, carbon capture and storage, hydrogen, and biogas.

NREL also found that meeting the growing demand for zero-carbon electricity means overall US generation capacity would need to roughly triple between 2020 and 2035, including a combined 2,000 gigawatts (GW) of wind and solar capacity. This would require growth rates in the range of 43 to 90 GW per year for solar and 70 to 145 GW per year for wind by the end of the decade, which would mean more than quadrupling the current annual deployment rates for each technology.

Although siting, permitting, and ramping up manufacturing for all of this new wind and solar generation will be challenging in this timeframe, NREL’s study and other studies suggest that it is technically and economically feasible. For example, about 930 GW of wind and solar capacity and 420 GW of storage projects are now awaiting approval to connect to the transmission system, according to Lawrence Berkeley National Lab. This year alone, developers are planning to install 29 GW of utility-scale solar. That’s more than double the current record and represents more than half of all new US capacity, according to recent Energy Information Administration (EIA) data. EIA also projects US battery storage capacity to more than double in 2023.

The federal Inflation Reduction Act (IRA) also will make a big difference by making available hundreds of billions of dollars in new incentives for these technologies. NREL’s 2022 Standard Scenarios study found that these federal incentives would accelerate the deployment of wind and solar, helping to reduce US power sector carbon dioxide emissions to 80 percent below 2005 levels by 2030.

NREL LAND-USE MODELING Total area occupied by wind turbines and solar photovoltaic infrastructure (solid colored boxes) is roughly equal to the land occupied by railroads. (Map courtesy NREL: Denholm et al. 2022. Examining Supply-Side Options to Achieve 100% Clean Electricity by 2035.)

Comparatively small footprint

NREL found that the land area directly occupied by wind and solar infrastructure by 2035 would make up less than 1 percent of the land in 94 percent of the country and less than or equal to 7 percent of total land area in just three states. A key reason why a relatively small amount of land is needed is because only 2 percent of the total area within a wind farm is occupied by wind infrastructure, while the remaining 98 percent is available for agriculture, grazing, or other uses. Offshore wind turbines also have a relatively small footprint and are able to use much larger turbines than land-based projects. Rooftop solar deployment, meanwhile, doesn’t require any land.

Of course, to deliver all this clean energy from wind-rich regions in the Midwest and Plains states to major load centers in the East will also require a lot of additional transmission lines. NREL found that total US transmission capacity would have to increase by 1.3 to 2.9 times current levels by 2035. This would require 1,400 to 10,100 miles of new high-capacity lines per year, assuming new construction began in 2026.

But the big news is NREL found that the total amount of land needed by 2035 to achieve our clean power goals with wind, solar, and long-distance transmission lines (19,700 sq. mi) would be:

equivalent to the land area currently occupied by railroads (18,500 sq. mi)
less than half the area of active oil and gas leases (40,500 sq. mi)
less than one-third of the area currently needed for ethanol production (59,500 sq. mi), and
only slightly more than the historically disturbed land area for coal mining (13,100 sq. mi).

Plus, NREL’s main “All Options” scenario projects roughly 250,000 wind turbines in the United States, which is considerably less than the nation’s 1.5 million oil and gas wells.

Environmental and public health benefits

Perhaps most important, though, is the fact that replacing fossil fuels with wind and solar will dramatically reduce the amount of land needed for mining, drilling, transporting, producing and using fossil fuels. Land used for these activities — and for disposing of coal ash and other wastes — often creates significant long-term environmental and public health problems for local communities.

By contrast, the land-use impacts of wind and solar projects tend to be short-term and reversible. As mentioned above, 98 percent of the land needed for a wind farm is available for agriculture, grazing, or other productive uses. Co-located solar and agriculture, or “agrivoltaic,” systems can make agriculture more sustainable by improving both energy and food production. Utility-scale solar projects also can be built on previously disturbed and contaminated land that was remediated for reuse, including brownfields, landfills, abandoned mine lands, invasive species-impacted land, gravel pits and quarries, Resource Conservation and Recovery Act (RCRA) and Superfund sites, and retired coal- and natural gas-power plant sites.

And, unlike fossil fuels, electricity generated by wind and solar does not use water or produce any emissions or wastes that can contaminate the air, land or waterways. When wind and solar projects reach the end of their useful lives, they can be removed and the land can be easily restored.

That said, mining some critical minerals for wind turbines, solar panels and batteries can have significant land-use impacts. Stringent policies and safeguards are needed to avoid, minimize and mitigate these impacts. Most of this mining currently occurs in other countries, but the IRA and the infrastructure law both include incentives to source more of these minerals domestically. In addition, several efforts are underway to recycle and reuse wind turbine components, solar panels and batteries instead of disposing them in landfills. (See more on these issues in these recent UCS blogs.)

Responsible siting required

Transitioning to a clean energy economy that relies heavily on wind and solar is a big and vitally important undertaking. Minimizing land use impacts will require responsible siting of wind and solar projects that avoids use of sensitive, or otherwise inappropriate, land and waters.

Fortunately, NREL’s modeling takes much of this into account in its report and related video:

For wind power, NREL excludes protected land (such as state and national parks, conservation areas, and water bodies), urban areas, and mountainous or difficult terrain. It also considers state and county setbacks as well as height ordinances and excludes land that conflicts with other existing infrastructure, such as buildings, roads, railroads and radar.

For utility-scale solar, NREL also excludes “prime” or “important” croplands and farmlands as designated by the US Department of Agriculture. It also limits potential new solar PV facilities to sites within 12.4 miles of existing transmission in most scenarios.

When these assumptions are taken into consideration, roughly 29 percent of the land in the lower 48 states is available for wind development and 39 percent could be used for solar development under most of NREL’s scenarios.

NREL doesn’t consider changes to land use patterns, including climate change impacts on land availability. But its implications are clear and heartening: If we develop wind and solar production in a responsible and sustainable way, the land-use demands are manageable and the environmental, public health, and land-use benefits of replacing fossil fuels will be enormous.

Originally published by the Union of Concerned Scientists, The Equation. By Steve Clemmer