Horizon: August 2, 2026 through August 2, 2027 — the window covers New York's statutory signing deadline, Connecticut's implementation date, expected UL 3700 system certifications, and the first year of FCC Covered List enforcement on power inverters.
The Calendar (6)
By end of 2026 (statutory deadline; no earlier date specified)scheduled
Governor Hochul must sign or veto the SUNNY Act (A.9111C/S.8512C)
Date basis: New York state legislative procedure — the bill was passed May 28, 2026, and reporting confirms Hochul has until the end of 2026 to act
This is the single highest-profile pending legalization decision in the balcony solar sector, covering the largest renter population among the states considering these bills.
Swing: A signature makes New York the ninth or tenth state (depending on final sequencing with other pending states) to legalize plug-in solar and, per reporting, takes effect 90 days after enactment; a veto or an unsigned bill lapsing at year-end would leave New York's roughly 53 million-household national rental-solar-access gap unresolved in the state and could chill legislative momentum in the 30 other states where similar bills have been introduced.
Watch for: An official signing or veto statement from the Governor's office, or any public statement on the bill's status.
90 days after New York enactment, if and when Hochul signsexpected
SUNNY Act takes legal effect in New York, if signed
Date basis: Reporting describing New York's standard 90-day post-enactment effective-date provision for this bill
This is the date balcony solar becomes legally usable without utility interconnection barriers in New York, contingent entirely on the prior signature catalyst.
Swing: If signed promptly, plug-in systems become legal for New York renters and homeowners within roughly three months; any delay in signature pushes this date out correspondingly, and if unsigned, this catalyst does not occur at all within the 12-month horizon.
Watch for: New York Department of State or Public Service Commission guidance implementing the law's utility-oversight exemption.
October 1, 2026scheduled
Connecticut's balcony solar provisions under HB 5340 take effect, including the 1,200-watt device cap and third-party certification requirement
Date basis: Connecticut Public Act 26-127 (HB 5340), signed by Governor Lamont on May 20, 2026, with an October 1, 2026 effective date for plug-in solar provisions
This is the first state-law implementation date in the horizon that directly tests whether UL 3700-certified or equivalent products are commercially available for compliant sale, given the law's requirement that devices be certified by an organization such as UL Solutions.
Swing: If UL 3700-certified complete systems are on the market by this date, Connecticut becomes a live proof-of-concept for the full legal-plus-safety stack; if certification lags, retailers and installers face a compliance gap between what the law requires and what hardware is actually certified.
Watch for: Connecticut PURA guidance or rulemaking on installation safety, and retailer listings citing UL 3700 or UL Solutions certification specific to Connecticut compliance.
Ongoing through 2026, pace described as 6–18 months from December 2025 standard finalizationexpected
Additional manufacturers complete UL 3700 full-system certification testing
Date basis: Manufacturer testing-pipeline estimates reported alongside the UL 3700 standard's December 2025 finalization
Full-system UL 3700 certification (beyond the single microinverter component already achieved by Hoymiles) is the benchmark multiple state laws reference by name as the compliance bar for complete plug-in kits.
Swing: Faster-than-expected certifications would let states with UL 3700-referencing statutes (including Connecticut and pending New York) point to a complete compliant product stack; continued delay would leave the market reliant on UL 1741-certified microinverters alone as the practical safety benchmark, as is presently the case.
Watch for: UL Solutions public certification database listings or manufacturer press releases naming specific UL 3700-certified complete systems (panel plus microinverter plus cordset).
Following the FCC's July 28, 2026 Covered List additionscheduled
FCC begins processing Conditional Approval applications for specific foreign-produced power inverter models
Date basis: FCC Public Notice DA 26-786 (released July 28, 2026), which appended guidance documents on Conditional Approval submission criteria
Most microinverters used in current plug-in balcony solar kits are foreign-manufactured; whether specific models secure Conditional Approval determines whether they remain importable and legally authorizable in the U.S.
Swing: Approved models continue receiving new FCC equipment authorizations and remain available to balcony-solar manufacturers; models without approval cannot receive new equipment authorizations, tightening supply of low-cost imported microinverters just as multiple state laws are taking effect.
Watch for: FCC equipment-authorization database entries showing new FCC IDs granted under Conditional Approval for power inverter models, or public announcements from manufacturers like Hoymiles, APsystems, or EcoFlow regarding compliance status.
January 1, 2029scheduled
Expiration of the FCC's software/firmware waiver window for previously authorized foreign-produced power inverter models, unless extended
Date basis: FCC Covered List guidance confirming the waiver covers only models authorized before July 28, 2026, and expires January 1, 2029 unless extended
Although this date falls beyond the 12-month horizon, it is the documented outer boundary of the current grace period for previously authorized foreign inverter models, relevant to any multi-year purchasing decisions balcony-solar retailers make now.
Swing: An extension (as occurred with the FCC's earlier drone and router Covered List waivers) would preserve continuity for existing inverter models; no extension would force a hardware transition for any still-reliant foreign models by that date.
Watch for: FCC rulemaking notices regarding waiver extensions, expected to surface analogous to the drone and router precedents cited in the FCC's own guidance.
Facts & Figures (7)
The claims behind this analysis, each with its verification status — including what is contested, unverified, or could not be established.
The NYS Legislature passed the Solar Up Now New York (SUNNY) Act (A.9111C/S.8512C) on May 28, 2026, and it has been awaiting Governor Hochul's signature since; her office has stated the bill is under review.
Sets the baseline status of the marquee catalyst in this calendar — NY's law is passed but not yet enacted.
✓ GROUNDED
Under New York's legislative procedure, Hochul has until the end of 2026 to sign or veto the SUNNY Act, and if she signs it, the law takes effect 90 days after enactment.
This is the only hard, sourced deadline governing when New York's law could take effect.
✓ GROUNDED
UL 3700, the first North American safety standard specifically for plug-in PV systems, was published in December 2025, and UL Solutions launched the associated certification program in January 2026.
UL 3700 is the certification standard multiple state laws reference by name, so its certification pace gates real-world compliance.
✓ GROUNDED
Hoymiles launched the HiFlow Pro microinverter in mid-July 2026 as the first U.S. product certified to meet UL 3700, though a correction from one outlet noted it is not yet certified by UL Solutions but designed to meet the standard.
Signals the certification pipeline is active but full UL Solutions-certified complete systems have not yet been confirmed to market.
✓ GROUNDED
On July 28, 2026, the FCC's Public Safety and Homeland Security Bureau added foreign-produced power inverters to its Covered List, restricting new equipment authorizations for unapproved foreign models on national security grounds; the restriction covers networked inverters used in home solar and battery systems among other categories.
This is a supply-side wildcard — most plug-in balcony solar microinverters currently sold in the U.S. are foreign-manufactured, and the new Covered List rule constrains which future models can be authorized.
✓ GROUNDED
Connecticut's HB 5340, signed by Governor Lamont, set balcony solar rules to take effect October 1, 2026, with a 1,200-watt cap and a requirement that devices be certified by a nationally recognized testing organization such as UL Solutions.
Connecticut is the first state with a dated implementation deadline that falls within this 12-month horizon, testing whether certified hardware is actually available by then.
✓ GROUNDED
New Hampshire's SB 540 (Chapter 89), signed by Governor Ayotte on May 28, 2026, took effect July 27, 2026, though its building-code provisions are contingent on a nationally recognized standard being certified.
New Hampshire's law is already in effect but has an internal trigger tied to UL 3700 certification completion, creating a second dated dependency on the certification timeline.
✓ GROUNDED