Berkeley Lab’s new report on the US utility-scale solar segment counts it to have contributed 18.5 GW AC in 2023
Solar PV + storage projects are gaining ground as 52 such facilities came online last year
With module prices falling, developers have oversized the DC array capacity relative to the AC inverter capacity to enhance revenue and reduce output variability
The US expanded its cumulative installed utility-scale solar PV capacity to 80.2 GW AC across 47 states, with the addition of a record 23.9 GW DC/18.5 GW AC in 2023 with most such projects built in the eastern Midwest, the mid-Atlantic, and southern parts of the country, according to the Lawrence Berkeley National Laboratory in a new report.
Titled Utility-Scale Solar, 2024 Edition, the report covers the empirical trends in deployment, technology, cost, performance, PPA pricing, and value in the US. It covers projects larger than 5 MW AC capacity. Texas led with 4.3 GW AC.
While utility-scale solar is largely well spread out in the US, there still are some regions that are yet to join the bandwagon. Montana and South Dakota, for instance, had their first large solar projects at 3x80 MW in 2023, and Alaska brought online a 6 MW facility. West Virginia’s maiden utility solar project came online this year with 80 MW capacity. Still, North Dakota and New Hampshire await their utility-scale solar turn, according to the report.
Storage-hybrid projects also proliferated last year as 15 existing projects added batteries, and 37 new ones. Together, 52 PV+ battery hybrid plants totaled 5.3 GW AC of PV and 3 GW/10.5 GWh storage came online.
In a recent report on hybrid power plant capacity in the US, Berkeley Lab counted 667 GW of hybrid capacity in the interconnection queues at the end of 2023, of which solar PV and storage accounted for close to 92% (see 667 GW Hybrid Project Capacity In US Interconnection Queues At 2023-End).
According to the utility-scale report of Berkeley Lab, among the utility-scale solar projects installed in 2023, the fixed tilt facilities are increasingly only being built on particularly challenging sites, or in the least sunny regions of the northeast, whereas tracking projects mainly dotted high-altitude states such as Oregon, Minnesota, Wisconsin, and Michigan.
Single-axis tracking projects are still the most popular as 96% of all new capacity utilizing tracking was based on this technology. Trackers remain popular as the upfront cost premiums have been on a downward spiral. According to Lawrence Berkeley researchers, tracking projects cost $0.2/W more than the fixed tilt projects on average.
The US market is also dominated by crystalline silicon solar modules. After a temporary decline in the relative growth in 2022, these expanded their market share again in 2023 to 72% of newly installed capacity. In comparison, thin-film modules reported a record annual deployment of 5 GW AC.
“As module prices have fallen (faster than inverter prices), developers have oversized the DC array capacity relative to the AC inverter capacity to enhance revenue and reduce output variability,” reads the report.
In terms of costs, the report writers believe that the installed costs of PV declined by 8% since 2022 to $1.43/W AC ($1.08/W DC) in 2023. Based on a sample of 7.1 GW AC representing 76 plants completed in 2023, costs fell by 75% since 2010.
According to the report, larger solar projects of over 50 MW AC capacity cost 13% less than the smaller ones within the range of 5 MW AC to 50 MW AC.
The levelized cost of energy (LCOE) of new 2023 projects increased slightly to $46/MWh before the tax credits but continued to fall to $31/MWh with the federal incentives. Nevertheless, for most new solar projects, analysts believe that Production Tax Credit is more beneficial than Investment Tax Credit.
As for power purchase agreement (PPA) prices, the newly signed longer-term PPA prices have increased since 2021 to an average of $35/MWh in 2023.
Going forward, the report counts at least 1.085 TW of utility-scale solar plant capacity in interconnection queues at the end of 2023. Of this, 53% or nearly 571 GW is paired with storage. The analysts caution though that historically only 10% of the requested solar capacity is built, as companies may submit exploratory interconnection requests or may face high interconnection costs or other development challenges.
The complete report is available for free download on Berkeley Lab’s website.
According to Wood Mackenzie and Solar Energy Industries Association (SEIA), the US installed 32.4 GW DC of new solar PV capacity in 2023, comprising 22.5 GW DC utility-scale solar (see 2023 US Solar Installations Set Record With 32.4 GW).