Project notes
About the project
This residence sits on Sunset Islands — a short chain of private islands in Biscayne Bay, reached by a single causeway. That geography is exactly why the homeowner wanted serious storage alongside his solar: when a hurricane takes the causeway down, utility restoration is often the last priority, and homes on the islands can wait days for FPL crews to reach them. Sprightful designed a 62-panel, 28.52 kW rooftop array paired with the largest battery bank of any home in our 22-project case study set — four Tesla Powerwall 3 units plus two Expansion Packs, stacking up to 81 kWh of usable storage.
For the roof itself we specified REC's Alpha Pure-RX 460 — a premium, all-black, lead-free module engineered in Norway and backed by REC's 25-year ProTrust warranty on product, performance, *and* labor. At ~22.3% efficiency and with a gridless "twin-panel" face, the Alpha Pure-RX squeezes more watts out of each square foot of Sunset Islands rooftop real estate and disappears into the architecture from street view — no silver gridlines, no visible busbars. Rather than add string inverters or microinverters to the stack, we DC-coupled the PV directly to the Powerwall 3 units — each Powerwall 3 ships with an integrated 11.5 kW solar inverter, so four of them in parallel comfortably handle the full 28.52 kW array with zero extra hardware, a tighter monitoring footprint, and better battery-charging efficiency (DC-to-DC instead of DC-AC-DC). Signed October 6, 2025; permit approved and final inspection passed December 22, 2025.