Solar Plus Storage Leads Hybrid Power Project Market in US

Solar plus storage hybrid projects stood out as frontrunners, with 213 projects out of 374


At the end of 2022, there were 374 hybrid power projects (each with capacities of 1 MW and above) in the United States, a 25% year-over-year increase, according to Lawrence Berkeley National Laboratory.

The hybrid projects comprise solar plus storage, wind plus storage, wind-solar plus storage, thermal plus storage, and solar plus wind power projects.

These projects accounted for 41 GW of generating capacity, a 15% increase from the previous year. The integration of energy storage surged to 5.4 GW/15.2 GWh, representing a 69% and 88% growth, respectively.

The annual briefing by Berkeley Lab provides a detailed map of existing hybrid or co-located projects across the U.S. It includes power purchase agreements (PPAs) and generation interconnection queues, providing information on development trajectories.

The report encompasses “co-located hybrids,” involving two or more resources (varied generations and/or storage) independently, and “full hybrids,” characterized by synchronized operations of co-located resources.

Solar plus storage hybrid projects were the most popular, with 213 projects. These projects had storage capacities of 4 GW/12.5 GWh, a storage-to-generator capacity ratio of 49%, and a storage duration of 3.1 hours.

Solar hybrid

Massachusetts led solar hybrid installations, with 80 projects, with 75 of these projects featuring a combination of solar plus storage. All these projects incorporated solar capacities below 7 MW.

California was second with 52 solar hybrid projects. Among these, 21 projects stood out for their substantial solar capacities, each reaching the threshold of more than or equal to 100 MW.

The hybrid landscape features an array of approximately 20 diverse configurations, encompassing combinations such as fossil hybrids, wind plus solar, geothermal plus, and more.

There was a surge in solar plus storage hybrid projects in 2022, with 59 out of 62 additions falling under this category. By the year’s close, there was almost as much storage capacity within solar plus storage hybrid projects as in standalone storage projects (~4 GW each). Solar plus storage edged out standalone storage by about 2 GWh (12.5 GWh vs. 10.4 GWh, respectively), underscoring the dominance of solar plus storage hybrid projects in the evolving energy landscape.

Hybrid power projects accounted for 37% (500 GW) of generation capacity, increasing from 31% in 2021. Hybrid power projects, including solar, represented 48% (457 GW) of this capacity. Proposed hybrid power projects are concentrated in the West, particularly within the California Independent System Operator region.

The Inflation Reduction Act (IRA) of August 2022 has introduced a significant shift in the energy storage landscape. Under the IRA, standalone storage systems now have access to the investment tax credit (ITC), eliminating the previous requirement for storage to be paired with solar to access the credit—a change set to take effect in 2023. While this change appears to lessen the incentive for combining batteries with solar installations, the full impact on the hybridization trend remains to be seen. This report acknowledges several factors contributing to the uncertainty around how this policy shift might influence hybridization.

The timeline of the IRA’s passage in August 2022 and the subsequent implementation of the standalone storage ITC in 2023 suggests that the market’s response is still evolving. Additionally, the closure of application windows in major regions and varying policies have shaped the context for this shift. Despite the potential impact of the standalone storage ITC, there are compelling reasons to believe that the hybridization trend might persist, underscoring the complexity of the evolving energy storage landscape.

In July 2023, the Federal Energy Regulatory Commission (FERC) issued Order No. 2023, titled “Improvements to Generator Interconnection Procedures and Agreements.” This order mandates transmission providers to permit multiple generating facilities or storage resources to co-locate on a shared site with a single point of interconnection. These entities can collectively submit a single interconnection request.

Notably, interconnection customers can now add resources to an existing request without it being classified as a “material modification,” which could have previously caused delays. The order’s impact on the trend toward hybridization is still uncertain, given that some regions already implement such practices.

Hybrid Project Proposals Surge

The interconnection queue data showed increased developer interest in hybridization. At the close of 2022, there were 51% more hybrid projects, representing 59% more generating capacity, in interconnection queues across the U.S. than at the end of 2021. There were 457 GW of solar capacity proposed as a hybrid, representing ~48% of all solar capacity in the queues.

Over 50% of hybrid power projects feature storage (358 GW), and wind hybrid projects totaled 24 GW (about 8% of wind capacity in the queues).

The report noted that operational solar plus storage projects, on average, have greater storage ratios (49%) and longer durations (3.1 hours) than other hybrid setups. Planned solar plus storage projects are inclined to have higher storage ratios and longer durations (although rarely exceeding 4 hours).

Almost 70% of hybrid capacity in the queues has applied for online deployment by 2025’s conclusion, with 12% having secured executed interconnection agreements (IAs). The ambition is for approximately 92% of hybrid capacity to be operational by 2028. Solar plus battery combinations are the primary choice for requested hybrid capacity additions until 2028.

There are over 56 GW (13%) of solar plus battery projects with executed IAs, while other hybrid types have much less, with standalone storage at 23 GW (7%).

In August last year, the Ministry of Power in India issued guidelines for competitive renewable power procurement by thermal and hydropower generators under the Generation Flexibility Program. The program intended to allow flexibility in generating and scheduling thermal and hydropower stations by bundling renewable energy and storage.

Wind-Solar hybrid projects have been hailed as the most viable option to manage intermittency issues faced by India’s standalone wind and solar power sources. Hybrid projects go a long way in optimizing land and transmission systems and providing a longer-duration power supply. On the sidelines of Mercom India Solar Summit 2022, experts stated how states like Rajasthan, Karnataka, Andhra Pradesh, Gujarat, and Haryana have seen the most hybrid project developments. While other states are slowly picking up on the pace for hybrid projects, the segment has a lot of ground to cover.

India’s installed hybrid capacity stood at 4.9 GW, according to data from Mercom’s India Solar Project Tracker.