Dive Brief:
- Hybrid power plants comprised 55.2% of active bulk solar capacity and 51.7% of active bulk energy storage capacity in the U.S. interconnection queue at the end of 2023, according to a Lawrence Berkeley National Laboratory briefing released last month. LBNL limited its analysis to plants with capacity greater than 1 MW.
- Hybrid plants accounted for a much smaller share of active wind (14%), gas (12.4%) and “other” generation pending interconnection, the briefing said.
- Inflation Reduction Act incentives for standalone energy storage installations did little to dampen interest in hybridized facilities in 2023, LBNL Energy Policy Researcher and briefing co-author Joe Rand said in a Sept. 30 webinar.
Dive Insight:
Solar-plus-storage facilities represented more than 92% of proposed hybrid bulk power plants and 86% of known hybrid bulk generation capacity in the U.S. interconnection queue as of year-end 2023, according to the briefing. The queue had 2,532 bulk solar-plus-storage proposals totaling approximately 575.5 GW of generating capacity at that time, with about 95% requesting to come online by 2029.
Proposed wind-plus-storage and wind-solar-and-storage facilities were a distant second and third, accounting respectively for 5% (35.3 GW) and 4% (26.2 GW) of generating capacity across 80 and 48 projects, LBNL said.
“Solar-plus-storage is by far the dominant configuration in the queue,” Rand said.
Installed solar-plus-storage capacity increased dramatically beginning in 2020 and overtook nuclear-plus-fossil, fossil-plus-solar and fossil-plus-storage as the leading configuration by 2022, according to the briefing.
Overall, the U.S. interconnection queue saw 18% more hybrid plants and 33% more generating capacity added in 2023. Hybridized proposed storage capacity in the queue increased by 48% while standalone proposed storage capacity rose by 52% in 2023, the briefing said.
The U.S. powered on 80 new hybrid power plants with 7.9 GW of operational generating capacity and 11.6 GWh of operational storage capacity in 2023, according to the briefing. Year over year, the hybridized facility count grew by 21%, generating capacity increased by 19%, storage capacity rose by 59% and storage output potential jumped by 67%.
Solar-plus-storage accounted for 66 of the plants added in 2023 and represents 288 of the 469 hybrid plants commissioned to date in the United States. Arizona (16) and California (15) added the most new solar-plus-storage plants in 2023, according to the briefing.
“The Southwest saw a lot of activity this year,” LBNL research scientist and briefing co-author Will Gorman said in the webinar.
Energy storage tends to account for a greater share of overall hybrid power plant capacity in regions with greater renewables penetration. In both California Independent System Operator territory and the non-ISO portions of the Western Interconnection, the median storage ratio is about 50% for existing solar-plus-storage facilities and 100% for proposed solar-plus storage plants, according to the briefing.
The storage ratio on the Hawaiian grid is already around 100%, Rand noted.
“It’s reasonable to assume that future hybrid plants will feature a relatively higher storage proportion compared to those that are already in operation,” he said.
Hybridized facilities account for at least one-third of total proposed solar capacity in several major grid regions, including CAISO (98%), the non-ISO West (81%), the Electric Reliability Council of Texas (49%), the Midcontinent Independent System Operator (35%) and the non-ISO Southeast (34%).
The LBNL briefing also analyzed 105 active and under-development power purchase agreements involving solar-plus-storage generators, mostly in Hawaii, California, New Mexico and Nevada. It found a notable increase in mainland PPA pricing from 2019 to 2024 and generally higher pricing for facilities with storage ratios at or near 100%.
Because power purchase agreements take time to negotiate, LBNL’s pricing analysis does not fully reflect the recent downtrend in lithium-ion battery pricing, Gorman said in the webinar.
But rising demand for firmer, lower-carbon generation may account for some of the recent observed increase in PPA pricing for hybrid facilities, Gorman said.
“PPA prices are a little bit more complicated than just taking in the raw materials costs,” he said. “If there is a huge amount of demand for these types of resources … people supplying these products can potentially offer a higher price.
