The US Department of Energy Solar Energy Technologies Office (SETO) and the National Renewable Energy Laboratory (NREL) have released the Solar Futures Study, which states that solar could account for as much as 40% of the nation’s electricity supply by 2035 and 45% by 2050 with aggressive cost reductions, supportive policies, and large-scale electrification.

The study focuses on three future scenarios, two of which assume that the US electric grid will be 95% decarbonized by 2035 and 100% decarbonized by 2050. The three scenarios were modeled with different assumptions – the reference scenario, the decarbonization scenario, and the decarbonization with electrification scenario.

The reference scenario outlines a business-as-usual future, including existing state and federal clean energy policies. However, it lacks a comprehensive effort to decarbonize the grid.

The decarbonization scenario assumes policies drive a 95% reduction from 2005 levels in the grid’s carbon dioxide emissions by 2035 and a 100% reduction by 2050. The scenario assumes aggressive cost-reduction projections for solar and other renewable and energy storage technologies than the ‘reference scenario.’ However, it uses standard future projections for electricity demand.

The decarbonization with electrification scenario goes further by including large-scale electrification of end-uses and analyzes the solar’s potential to contribute to a future with complete decarbonization of the US energy system by 2050.

Under the reference scenario, installed solar capacity increases by a factor of seven by 2050, and grid emissions decline by 45% by 2035 and 61% by 2050, relative to the 2005 levels.

Meanwhile, the decarbonization scenarios show cumulative solar deployment of 760 –1,000 GW by 2035, serving 37%–42% of electricity demand, while the remainder is met largely by other zero-carbon resources, including wind.

Similarly, the decarbonization and the decarbonization with electrification scenarios predict a cumulative solar deployment of 1,050–1,570 GW by 2050, serving 44%–45% of electricity demand, with the remainder met by wind, nuclear, hydropower, and other renewables.

The study suggests that for solar to account for as much as 40% of the nation’s electricity supply by 2035 and 45% by 2050, the US must install 30 GW(AC) of solar each year between 2021 and 2025 and ramp up to 60 GW(AC)/year from 2025 to 2030.

Under decarbonization and the decarbonization with electrification scenarios, the study found that the grid can be decarbonized to 95% by 2035 without increasing electricity prices due to technological improvements and enhanced demand flexibility.

Compared to a reference scenario, the net incremental cost of a 100% decarbonized grid in 2050, coupled with further electrification of buildings and transportation, will be roughly $210 billion. Avoided climate damages and improved air quality will result in overall net savings of $1.7 trillion.

The study suggests that the solar industry could employ 500,000–1.5 million people by 2035.

In the decarbonization with electrification scenario, solar electricity could power about 30% of all building end uses and 14% of transportation end uses by 2050. Simultaneously, energy storage with 12 hours or less of energy capacity expands from 24 GW in 2019 to more than 1,600 GW in 2050.

The study points out that in 2050, ground-based solar technologies will require a maximum land area equivalent to 0.5% of the contiguous US surface area, which could be met using less than 10% of potentially suitable disturbed lands, avoiding conflicts with high-value lands in current use.

The report suggests that the availability of materials will likely not limit solar growth, especially with materials recycling.

Technology breakthroughs and more participation in recycling and the circular economy will maximize the use of recoverable materials and yield benefits in energy and materials security, improved social and environmental outcomes, and new jobs and domestic manufacturing opportunities.

According to the US Solar Market Insight 2020 Year-in-Review report, released by the Solar Energy Industries Association (SEIA) and Wood Mackenzie, the US solar industry grew 43%. The US installed a record 19.2 GW of capacity in 2020.