In a continuous effort to shift to a ‘storage-first strategy’, US residential installer Sunrun ended the last quarter of 2024 with an energy storage attachment rate of 62%.
Up from the 60% registered during Q3 2024, the attachment rate for customers opting for batteries with their solar PV installation varies per region, with the two island regions of Hawaii and Puerto Rico at nearly 100% energy storage attachment rate followed by California with approximately 89% and Texas at 66%. The rest of the country, however, was at 10% during Q4 installations.
Try Premium for just $1
- Full premium access for the first month at only $1
- Converts to an annual rate after 30 days unless cancelled
- Cancel anytime during the trial period
Premium Benefits
- Expert industry analysis and interviews
- Digital access to PV Tech Power journal
- Exclusive event discounts
Or get the full Premium subscription right away
Or continue reading this article for free
As storage capacity installation grew in double digits during Q4 2024, added solar PV grew by 6% year-on-year to 242MW in Q4 2024. On the other hand, 392MWh of storage was added in Q4 2024, up 78% from the same period in 2023.
The company’s total installed storage capacity reached 2.5GWh, while installed solar PV is at 7.5GW at the end of 2024.
For the third quarter in a row, the company generated a positive cash generation, with US$34 million in Q4 2024. Sunrun expects this to continue throughout every quarter in 2025, as it will prioritise its cash generation.
As a consequence of that priority, the company expects to target higher-value offerings, which comprises the increase in the storage attachment rate by ten points up to 66%. It ended 2024 with a storage attachment rate of 57%.
Storage to offer backup power capabilities
“We continue to advance programmes that generate value for customers, the grid and Sunrun. We have 16 grid service programmes active across the country, with over 20,000 customers participating, said Mary Powell, Sunrun’s CEO, during an earnings call following results of Q4 2024.
As the company continues to increase the attachment rate of storage and its installations, this offers Sunrun more grid service opportunities. It currently has 16 grid programmes across nine US states, with virtual power plants (VPPs) in states such as California, Puerto Rico. In October, it unveiled its latest programme in New York.
“During 2024, Sunrun’s virtual power plants successfully supported power grids across the country with a combined instantaneous peak of nearly 80 megawatts, a capacity greater than many traditional fossil-fuel power plants. Sunrun is leading in establishing a platform to turn homes and vehicles into smart, controllable load that can be dispatched into, and improve the electric grid,” added Powell.
In September, PV Tech spoke with Chris Rauscher, head of grid services & VPPs at Sunrun, about the use of VPPs and how these could open new residential solar PV and storage markets in the US if used to power data centres (Premium access).
Finally, Powell also commented on the change of administration and how the importance of energy independence for American citizens would not impact the demand for residential solar and/or storage systems.
“The fundamental long-term demand drivers for our business are incredibly strong and unrelated to any political party affiliation. Americans want greater energy independence and control of their lives and their pocketbooks.
“The country also needs more power from all sources to fuel rapid growth in electrification, and data centers, and our growing fleet of energy resources will be part of the solution. For these reasons, it is no surprise that support for the energy we provide spans across all party lines,” said Powell.
Domestic content bonus to increase as more domestic equipment becomes available
Furthermore, the 10% investment tax credit (ITC) adders will make solar more affordable and accessible to a broader consumer population, according to Sunrun.
Domestic content qualifications accounted for 36% of the company’s volume in Q4 2024, and is expected to keep rising in the coming quarters as more domestically-produced equipment becomes available.
The weighted average ITC in Q4 2024 was at around 39.8%, up from the 37.7% registered in the previous quarter. In the first month of 2025, the numbers have continued to increase up to 42%, while the company expects to have a full-year weighted average ITC around 44%.
Looking ahead in 2025, the company targets to add between 170-180MW of solar PV during Q1 2025, while for the full year it expects the volume to be nearly flat year-on-year. Storage capacity is expected to see a 30% growth, year-on-year, in Q1 2025 with 265-275MWh of added capacity.
Sunrun’s guidance for cash generation in 2025 sits in the range of US$200 million to US$500 million.
Earnings call transcript from Seeking Alpha.
