By Galen Barbose and Naïm Darghouth, Lawrence Berkeley National Laboratory, Electricity Markets & Policy Group January 2, 2020
Berkeley Lab’s annual Tracking the Sun report summarizes installed prices and other trends among grid-connected, distributed solar photovoltaic (PV) systems in the United States. The latest edition of the report, released in November, focuses on systems installed through year-end 2018, with preliminary trends for the first half of 2019. The analysis is based on project-level data from approximately 1.6 million systems, representing 81% of all distributed PV systems installed in the United States through the end of 2018.
Key findings from this year’s report include the following:
Distributed PV Systems Keep Getting Bigger, More Efficient. Median system sizes in 2018 grew to 6.4 kW for residential and roughly 50 kW for non-residential systems, though the spread in system sizes is also quite wide—especially for non-residential systems, with 20% larger than 200 kW. Increasing system sizes over time partly reflect a steady growth in module efficiencies, which rose a full percentage point to a median of 18.4% among systems installed in 2018. The report also details trends among other ystem design and project characteristics, including panel orientation, inverter loading ratios, solar- plus-storage, use of module- level power electronics, and third-party ownership.
Installed Prices Continued to Fall through 2018 and into 2019. The report focuses its analysis of installed prices specifically on host-owned distributed PV systems. Among these systems national median installed prices fell year-over-year by 5-7% across the customer segments shown in the figure below. Those declines are broadly in-line with trends over the past five years. National median installed prices in 2018 were $3.7/W for residential, $3.0/W for small non-residential, and $2.4/W for large non-residential systems. Considerably lower prices are observed among many systems, however.
Installed Prices Vary Widely Across Projects. For example, among residential system installed in 2018, prices for host-owned systems ranged from $3.1/W to $4.5/W between the 20th and 80th percentile levels, and prices for small and large non- residential systems varied across similarly wide ranges. The report explores sources of that pricing variability, including differences in system size, module- and inverter-type, mounting-type, location, installer, host customer-type, and new construction vs. retrofits. This year’s report also contains a more-formal statistical analysis to isolate the effects of individual pricing drivers, including characteristics of the local PV market related to market size, competition, and installer experience, among other factors.
Within the residential segment, median prices fell year-overyear (YoY) by roughly $0.0-0.2/W across the five largest states in the dataset. Notably, all five sawlower annual price declines than the aggregate national drop. By extension, smaller markets saw larger declines, suggestive of the greater cost-saving opportunities that may exist in less mature markets. Among non-residential systems, YoY changes in median installed prices varied much more dramatically across states, as might be expected given the more-diverse set of projects and smaller sample sizes. For that reason, YoY changes in median prices for nonresidential systems can be somewhat erratic, at both the state and national levels.
Notes: Installed-price trends are based on a subset of the larger data sample, consisting of 680,000 host owned systems. Solid lines represent median installed prices, while shaded areas show the 20th to 80th percentile range. Large residential systems consist of projects larger than 100 kW and, if ground-mounted, less than 5 MW-AC. Ground-mounted projects larger than 5 MW-AC are addressed in Berkeley Lab’s forthcoming Utility-Scale Solar Report.
The report can be downloaded via trackingthesun.lbl.gov. For questions on the report, feel free to contact
Galen Barbose at Lawrence Berkeley National Laboratory (510-495-2593, GLBarbose@lbl.gov) or Naïm Darghouth (510-486-4570, NDarghouth@lbl.gov).