SolarAPP+ Performance Review (2024 Data)

Nissen, Katie [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000349372617); Dalecki, Emily [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000210790451); O'Shaughnessy, Eric [Clean Kilowatts, Plymouth, MI (United States)]; Xu, Kaifeng [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000319832694); Akar, Sertac [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000195980037); Frey, Noah [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000183453475); Botin, Pablo [National Laboratory of the Rockies (NLR), Golden, CO (United States)]; Castelao, Guilherme [National Laboratory of the Rockies (NLR), Golden, CO (United States)]; Tagani, Jaclyn [National Laboratory of the Rockies (NLR), Golden, CO (United States)]

doi:10.2172/3016084

DOE OSTI · 3016084

SolarAPP+ Performance Review (2024 Data)

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Abstract

The Solar Automated Permit Processing Plus (SolarAPP+) platform is an online portal to facilitate and expedite rooftop solar photovoltaic (PV) and battery storage permitting processes. SolarAPP+ allows PV contractors to upload system specifications, have that information automatically reviewed for code compliance, and receive instant approval for code-compliant systems, reducing authority having jurisdiction (AHJ) staff time needed for review. SolarAPP+ also provides inspection checklists to verify installation practices and adherence to approved designs. This report is part of an ongoing series of reviews of SolarAPP+ performance. Consistent with previous performance reviews, we summarize SolarAPP+ adoption trends to date and compare various metrics for PV systems permitted through SolarAPP+ versus systems permitted through traditional AHJ permitting processes. As of the end of 2024, 799 AHJs had expressed interest in the platform, with 264 fully adopting (215) or piloting (49) the platform. In 2024, 861 installers submitted 37,393 permits through the SolarAPP+ platform, including 27,375 permits for PV+storage systems. SolarAPP+ permits accounted for around 43% of all permits issued in all participating AHJs, and more than 60% of all permits in several participating AHJs. We compare permitting timelines through SolarAPP+ to traditional AHJ permitting processes to assess the platform's performance. Consistent with previous SolarAPP+ performance reviews, we find that permitting timelines are significantly shorter for SolarAPP+ projects. Based on median timelines, a typical SolarAPP+ project is permitted and inspected 12 business days sooner than traditional projects. We estimate that automatic SolarAPP+ permitting saved around 18,400 hours of AHJ staff time in 2024. Finally, we estimate that SolarAPP+ eliminated over 100,000 business days in permitting-related delays in 2024.

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14 SOLAR ENERGY 25 ENERGY STORAGE 97 MATHEMATICS AND COMPUTING energy storage permitting photovoltaic residential solar solar SolarAPP+

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Nissen, Katie [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000349372617), Dalecki, Emily [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000210790451), O'Shaughnessy, Eric [Clean Kilowatts, Plymouth, MI (United States)], Xu, Kaifeng [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000319832694), Akar, Sertac [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000195980037), Frey, Noah [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000183453475), Botin, Pablo [National Laboratory of the Rockies (NLR), Golden, CO (United States)], Castelao, Guilherme [National Laboratory of the Rockies (NLR), Golden, CO (United States)], Tagani, Jaclyn [National Laboratory of the Rockies (NLR), Golden, CO (United States)]. 2026-01-29. SolarAPP+ Performance Review (2024 Data). https://doi.org/10.2172/3016084

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