The U.S. Will Need a Lot of Land for a Zero-Carbon Economy
The U.S. Will Need a Lot of Land for a Zero-Carbon Economy
At his international climate summit last week, President Joe Biden vowed to cut U.S. greenhouse gas emissions in half by 2030. The goal will require sweeping changes in the power generation, transportation and manufacturing sectors. It will also require a tremendous amount of land.
Wind farms, solar installations and other forms of clean power take up far more space on a per-watt basis than their fossil-fuel-burning brethren. A 200-megawatt wind farm, for instance, might require spreading turbines over 19 square miles (49 square kilometres). A natural-gas power plant with that same generating capacity could fit onto a single city block.
Achieving Biden’s goal will require aggressively building more wind and solar farms, in many cases combined with giant batteries. To fulfill his vision of an emission-free grid by 2035, the U.S. needs to increase its carbon-free capacity by at least 150%. Expanding wind and solar by 10% annually until 2030 would require a chunk of land equal to the state of South Dakota, according to Bloomberg and Princeton University estimates. By 2050, when Biden wants the entire economy to be carbon free, the U.S. will need up to four additional South Dakotas to develop enough clean power to run all the electric vehicles, factories and more.
Power Densities: Renewables Need More Space
Wind-energy footprint
including turbine spacing
296 m2
Hydropower
14 m2
Solar
0.8 m2
Coal
0.3 m2
Nuclear
0.1 m2
Natural gas
37 m2
Wind
Note: Assumes 100-watt television operating year-round
To be clear, Biden’s plan doesn’t need to entirely rest on wind and solar. Nuclear energy, which requires far less space, is also emission free. Same for hydroelectric power. Plus, wind farms can be installed at sea. Solar panels work wonderfully on rooftops. And plenty of companies are placing bets that fossil-fuel plants can be retrofitted to burn hydrogen or equipped with systems to capture their carbon dioxide emissions.
But no matter how you slice it, the U.S. will need to dedicate more land to producing power in an emissions-free future. Here’s how researchers at Princeton University’s Net-Zero America project estimate it can be done.
Today, the U.S. Uses 81 Million Acres to Power Its Economy
51.5 million acres
Liquid biofuels: ◼ Soy ◼ Corn farming
8.7M
Hydropower
7.1M
◼ Solar and ◼ wind energy farms
4.8M
Petroleum and gas pipeline easements
3.0M
Oil and gas drilling operations, fracking-sand mining
4.8M
Power line easements
0.6M
Coal mining, transport and waste storage operations
0.23M
Nuclear power plants and uranium mining
0.15M
Fossil-fuel power plants
Right now, the current U.S. energy sector requires about 81 million acres (33 million hectares) of land. That estimate includes not only energy sources fueling the electric grid, but also transportation, home-heating and manufacturing.
Energy Land-Use Framework
81 million acres
51.5 million acres
Biofuels
(dedicated corn for ethanol,
soy for biodiesel farmland)
8.7
Hydropower
6.7
Wind farms
(total footprint)
4.8
Power lines
3.5
Oil/
petroleum
products
4.4
Natural gas
0.07
Direct wind
footprint
0.6
Coal
0.5
Solar
0.23
Nuclear
0.15
Power plants
Two-thirds of America’s total energy footprint is devoted to transportation fuels produced from agricultural crops, primarily corn grown for ethanol. It requires more land than all other power sources combined but provides just 5% of the nation’s energy, making it the most land-intensive major fuel source.
= 1 million acres
8.7 million acres
Hydropower
3.5 million acres
Oil/gasoline
51.5 million acres
Biofuels
Here’s how 81 million acres of energy acres lumped together looks on a U.S. map. Our current energy footprint is about the size of Iowa and Missouri combined, covering roughly 4% of the contiguous U.S. states.
Princeton University’s Net-Zero America Project maps various pathways to reaching a carbon-free U.S. by 2050. Each path has unique land-use challenges, from siting hundreds of new nuclear reactors to finding homes for one million wind turbines.
The most land-intensive plan eliminates all fossil fuels and nuclear plants. Wind and solar provide 98% of electric power by 2050. The U.S. energy footprint quadruples in size. Wind farms occupy land areas equivalent to Arkansas, Iowa, Kansas, Missouri, Nebraska and Oklahoma.
In this highly electrified economy, wind and solar provide four times the electric power capacity of the 2020 U.S. grid. Electricity powers all vehicles, heats homes and powers many industrial processes. When demand peaks and the grid needs an extra boost, it will come from a mix of batteries, hydropower and combustion turbines burning carbon-free synthetic fuels and hydrogen.
Is there even enough open land to build 250 million acres of new wind farms?
The short answer is yes, according to estimates from the U.S. Department of Agriculture.
The contiguous U.S. is home to 654 million acres of pasture and 391 million acres of farmland. In many instances, wind turbines can be incorporated into those areas and have limited impact.
Plenty of U.S. ranch and farm owners already lease land for annual royalty payments, totaling $820 million last year.
Princeton's study estimates that 11% of electric power could come from offshore wind farms by 2050. Another 3% of generating capacity could come from rooftop solar. In sunnier places, such as California, rooftop solar could generate 74% of electricity, according to the U.S. National Renewable Energy Laboratory.
If the U.S. wants a carbon-free economy by 2050 using the least amount of land, it will need to rely far less on wind and solar and instead build hundreds of nuclear plants and natural gas plants outfitted with systems to capture the carbon dioxide before it escapes into the atmosphere.
In this model, the current pace of wind and solar development remains constant, but carbon-capture and nuclear power grow at historically unprecedented rates.
Wind and solar would contribute 44% of electricity generation, and 50% would come from emission-free nuclear and natural gas power plants with carbon-capture technology. Methane, an especially potent emission that's a central component of natural gas, would be aggressively curtailed via better monitoring of pipelines and other equipment. Any leaks would be offset by systems that filter greenhouse gases from the air, improved farming methods and other means.
Under this scenario, the U.S. would need to build 250 nuclear plants with capacity of at least 1 gigawatt, or several thousand smaller modular reactors. Natural gas and nuclear energy are very compact power sources. A conventional 1-gigawatt reactor operating on 1,000 acres produces the same power as a wind farm spanning 100,000 acres.
Needless to say, expanding nuclear power will present serious land-use challenges. While no one wants a power plant in their backyard, many people don’t want nuclear power on their planet.
To make 300 new natural-gas fired power plants emission-free, a network of carbon-capture pipelines and storage facilities would be built. That would require land easements totaling 500,000 acres, about half the size of Rhode Island. To drive down costs, Princeton estimates it will take about $100 billion in private and public investment in CO2 capture demonstration projects over the next decade.
The most difficult land-use challenge in any scenario may be building transmission lines.
For example, in 2011, former President Barack Obama created the Rapid Response Team for Transmission to speed the permitting of five Western transmission line projects. Only one is under construction so far. Three still face permitting delays. The fifth was canceled.
Transmission line capacity would need to more than triple under the high-renewable scenario laid out by the Princeton researchers. Without it, many new wind and solar projects would be stranded.
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