In 2024, new installations of large-scale ground-mounted solar in the United States reached 30GW, a significant 56% increase compared to the 19GW added in 2023. This accounted for over 54% of all new electricity generation capacity added nationwide last year.
These figures are recorded in the latest 2025 data update report on large-scale solar installations from Lawrence Berkeley National Laboratory (LBNL).
The data reveals that the 2024 growth was not evenly distributed geographically. It was concentrated primarily in Texas, the Midwest, and non-ISO (Independent System Operator) regions of the West and Southeast.
The ERCOT (Electric Reliability Council of Texas) grid led with 7.6GW of new large-scale solar capacity added in 2024. It was followed by the MISO (Midcontinent Independent System Operator) grid (6GW), and the non-ISO regions of the West and Southeast (primarily Florida), each adding approximately 4.7GW.
The LBNL report provides multi-dimensional data covering large-scale solar deployment and the overall market.
Installed Costs of Large-Scale Solar
LBNL’s report indicates that the average capacity-weighted installed cost for large-scale solar power plants saw a slight increase between 2023 and 2024, rising from $1.59 per watt (AC) to $1.61 per watt (AC). This “solid” 2024 data is based on records from 425 projects, covering 92% of the year’s new capacity.
However, significant regional cost variations existed. The ERCOT region had the lowest prices, below $1.50 per watt (AC), while most other ISO regions hovered around $1.50 per watt. The New York ISO (NYISO) was a notable exception, with prices exceeding $2.00 per watt.
LBNL attributes these differences to factors such as land availability, prevailing local labor costs, and expenses for transmission network upgrades.
Nationwide, the average Levelized Cost of Energy (LCOE) for large-scale solar increased by 13% last year: rising from $53 per MWh to $60 per MWh without factoring in tax credits, and from $36 per MWh to $41 per MWh after accounting for the Investment or Production Tax Credit. The report cites rising financing costs, increased capital expenditures, and slightly lower projected performance as factors driving the national average LCOE increase.
Single-Axis Trackers Dominate, Crystalline Silicon Expands
Nearly all (99%) new large-scale solar projects built last year utilized single-axis trackers instead of fixed-tilt structures. In 2024, only 12 projects used fixed-tilt mounts, compared to 236 projects employing tracking systems.
The cost of tracking systems decreased in 2024, and their ability to generate more electricity per installed watt made them more attractive to project developers. Fixed-tilt systems are now primarily used only in “special” circumstances, such as extreme terrain or areas with higher severe weather risks.
Deployment of crystalline silicon (c-Si) module technology also expanded significantly in the large-scale sector last year. Annual c-Si PV installations nearly doubled, jumping from approximately 13.3GW in 2023 to 23.4GW in 2024.
In contrast, thin-film module installations remained relatively stable, increasing only slightly from 5.24GW in 2023 to 6.13GW in 2024—a gain of less than 1GW. This is likely because First Solar remains the sole major domestic thin-film manufacturer.
As of the end of 2024, the cumulative installed capacity of c-Si modules in US large-scale solar reached 79.19GW, compared to 30.74GW for thin-film technology.
