The United States needs to deploy 40–90 GW of solar and 70–150 GW of wind energy every year until 2030 to decarbonize the country’s power sector by 2035, a report by the U.S. National Renewable Energy Laboratory (NREL) and the U.S. Department of Energy (DOE) has said.

The report estimates the move to cost $330-$740 billion in additional power systems costs between 2023 and 2035.

Electricity generated from renewable sources totaled 795 million megawatt-hours (MWh) in the U.S. in 2021, surpassing the 778 million MWh of electric power generated from nuclear reactors. According to Energy Information Administration (EIA), wind and solar energy primarily contributed to the boost in power generation from renewables.

The report recommends concentrating on four scenarios — All options, Infrastructure renaissance, Constrained, and No carbon capture and storage (CCS) technologies.

Wind and solar provide 60%–80% of the generation in the least-cost electricity mix in all the main scenarios.

The report suggests that research and development, manufacturing, and infrastructure investment decisions will help determine the exact technology mix costs over the next decade. It also says that the mix of technologies to achieve the net-zero carbon target in power generation is the main uncertainty in all four scenarios.

The report projects that the overall generation capacity would grow to roughly three times the 2020 level by 2035, including a combined 2 TW of wind and solar capacity. This would require growth rates in the range of 43-90 GW every year for solar and 70-145 GW annually for wind energy by the end of 2030, which would more than quadruple the current annual deployment levels for each technology in many scenarios.

The study highlights that the grid emissions could decline to 68-78% below 2005 levels by 2030, while the longer implications of the new laws are uncertain.

Additionally, NREL represented seasonal storage in one of its models as clean hydrogen-fuelled combustion turbines, which can also include a variety of technologies under various stages of development, assuming they achieve similar costs and performance.

The report found significant uncertainty about seasonal storage fuel pathways, including synthetic natural gas, ammonia, and alternative conversion technologies such as fuel cells.

Bipartisan law and Inflation Reduction Act

The report comes just after the U.S. announced the Inflation Reduction Act (IRA), which along with the Bipartisan Infrastructure Law, is estimated to reduce the economy-wide greenhouse gas emissions in the country to 40% below 2005 levels by the end of the decade.

Apart from higher technology costs, the report also highlights a few critical hurdles in decarbonizing the power sector. One of them is the investment required in doubling or tripling transmission capacity for connecting the new green energy capacity to the grid. However, the report says that the Inflation Regulation Act could mitigate the cost of installing new infrastructure.

The report suggests analyzing the unprecedented deployment rates that require a corresponding growth in raw materials, manufacturing units, and a skilled workforce. NREL recommends continued research, development, demonstration, and deployment support to bring emerging technologies to the market.