Berkeley Lab has released the latest edition of its Tracking the Sun annual report, detailing significant trends in distributed solar photovoltaic (PV) systems across the United States. This year’s report, based on data from approximately 3.7 million systems installed through the end of 2023, provides insights into system characteristics, design, pricing, and the rising prevalence of solar-plus-storage systems.

The report has highlighted several key findings that provide a detailed overview of current trends in the solar energy market. Among the most significant findings include:

Growing residential system sizes

Residential PV systems have increased in size over the past two decades, reaching a median of 7.4 kW in 2023. This growth aligns with advancements in module efficiency, allowing for more capacity despite spatial constraints like shading and roof obstructions. Roof-coverage ratios have remained stable, typically between 20-40%.

Diverse non-residential adoption

In 2023, non-residential PV systems were primarily installed on commercial properties (50%), with agricultural properties making up about one-third of installations. Notably, small agricultural systems (

Source: Energy Markets & Policy

Increasing battery storage integration

Battery storage attachment rates continue to rise, with 12% of new residential PV systems and 8% of non-residential systems including storage in 2023. Hawaii leads with exceptionally high attachment rates of 95% for residential and 88% for non-residential systems. In California, residential storage attachment rates climbed to 14%, with new net billing tariffs boosting these figures to around 60% by year-end.

Source: Energy Markets & Policy

Price trends

Median installed prices for residential PV systems fell by approximately $0.1/W from 2022 to 2023, continuing a decade-long decline. Conversely, non-residential system prices increased for the first time in 15 years, rising by $0.1-0.2/W. The report highlights that pricing variability exists due to factors such as project characteristics, local market conditions, and regulatory environments.

Source: Energy Markets & Policy

Pricing variability

Installed prices for stand-alone PV systems show significant variability, ranging by about $2/W between the 20th and 80th percentiles for residential and small non-residential systems, and about $1.4/W for large non-residential systems. Key pricing drivers include the inclusion of battery storage, system size, and whether the installation is on new versus existing residential construction.

Source: Berkeley Lab

The 2024 "Tracking the Sun" report provides a comprehensive overview of the evolving solar landscape in the United States. It highlights critical developments in system sizes, technological advancements, and market trends, offering valuable insights into the future of solar energy. As the industry continues to innovate and adapt, these trends will play a pivotal role in shaping the trajectory of renewable energy in the country.