Home batteries are now a leading-edge solution for managing energy costs and power backup. Many systems pair solar with external inverters, and that approach remains a solid choice for a wide range of homes. At the same time, some newer batteries incorporate integrated power conversion to accept direct DC input while still providing the flexibility of an AC-coupled architecture. This is ideal in new solar scenarios as this can streamline energy flows, reduce installation steps, and help capture more of the energy available.
The aPower S is the epitome of the new home battery innovation.
It’s FranklinWH’s latest home battery engineered to natively connect to solar, turning every ray of sunlight into usable stored energy with much higher efficiency than conventional storage systems. By integrating the power conversion system (PCS) directly into the battery, the aPower S minimizes external hardware, simplifies installation, and unlocks the full output of today’s high-performance solar arrays. Lastly, the aPower S is backwards compatible and can be AC coupled with the previous aPower versions, providing additive capacity, power output, and enhanced system reliability.
Direct Solar Connection — Designed to Capture More, Faster
The aPower S accommodates a direct DC solar input, letting energy from your panels flow straight into the battery without unnecessary conversions. This results in higher capture efficiency and more of your own generation stored for later. Its proprietary Global MPPT (Maximum Power Point Tracking) algorithm continuously tunes to real-world conditions, such as clouds, partial shade, varied roof pitches, even east–west splits, so the system always hits the maximum power point for solar panels and maximizes solar harvest instead of leaving watts on the table.
- High PV accommodation: Up to 20 kW of solar input per unit, well-suited to large homes and high-output modules.
- Fast recharge: 8 kW charging rate helps rebuild reserves quickly.
- Multi-channel design: Connect independent arrays on different roof planes/buildings and add capacity over time without re-wiring the whole system.
- Unrivaled efficiency: Industry’s highest round trip efficiency (RTE) of 90.5%, minimal energy loss.
- Handles high-current solar panel: Industry-leading solar input capacity of 15 A per channel.
Whole-Home Backup without Load Constraints
Energy storage isn’t only about hours it claims on the spec sheet. Rather, it’s about what your home can actually run when it matters. The aPower S is sized and engineered for your whole real lifestyle, not just a handful of “critical loads.”
- 15 kWh usable capacity and 11.5 kW continuous power per unit (with PV): Enough to run your entire home, not just the basics such as lights and a refrigerator.
- High surge output: Built to easily handle start-ups of heavy-duty appliances (eg., a 5-ton A/C) and simultaneous appliance use without nuisance trips.
- Scales as needs grow: Expand up to 225 kWh per system (15 units per aGate) for larger homes, EV-heavy households, or future electrification plans.
- Unique backward and cross-version compatibility: The aPower S can be AC coupled with the aPower 2 for added capacity, power and reliability.
- UPS-level power quality: Handles all types of home loads and offers exceptional power stability and reliability.
In practice, that means comfort and continuity: air conditioning stays steady, cooking and cleaning continue as normal, EVs keep charging, and the list goes on and on. Your daily routines go uninterrupted as if an outage has never happened.
If an extended blackout ever drains the battery completely, Black Start takes over: when sunlight returns, the system automatically recharges and restarts—no breakers to flip, no manual reset, just a quiet return to normal.
Built to Stand the Test of Time
Power systems should be able to protect against daily wear, and the aPower S is engineered to prove it. It undergoes rigorous tests to ensure it can endure harsh conditions: extreme temperatures, storms, salt air, dusty garages, and years of daily cycling.
- Proven durability: 20,000+ safety and reliability tests validate the design under thermal stress, vibration, ingress, long-cycle operation, and more.
- Long-term warranty assurance: Industry-leading 15-year or 60 MWh throughput warranty, giving confidence for both occasional backup and frequent daily cycling.
- Exceptional weatherproof capability: IP67 rating keeps out dust and shields against heavy rain—resilient in storm seasons and outdoor installs.
- Broad operating temperature range: Works from -4° F to 131° F, suitable for desert summers, snow-belt winters, and coastal climates.
- No fans, fewer failure points: Natural convection cooling avoids moving fans as a common point of failure, cuts maintenance, and keeps sound to about 30 dBA—quiet enough for living spaces.
Technology That Looks as Good as It Works
Energy hardware doesn’t have to be industrial and unattractive. The aPower S well blends itself into modern architecture with:
- Lightweight aluminum-alloy enclosure: A clean, modern profile that’s easy to place and visually unobtrusive, with the rigidity and corrosion resistance homeowners expect in coastal or humid areas.
- Automotive-grade exterior finish: Durable coatings help the surface resist fading and abrasion over years of sun, rain, and routine cleaning, so the unit keeps its fresh, sleek look.
- Customizable LED light strip: Offering both status cues and unique ambient glow, the strip communicates state of charge and system activity at a glance.
Whether mounted indoors or outdoors, the aPower S reads as part of the architecture—sleek, quiet, and purposeful, rather than a piece of industrial gear bolted to the wall.
Who Is the aPower S for?
Here’s where the aPower S is the most compelling choice: whether you’re grid-only today or pairing storage with solar now or off-grid:
- Large properties or advanced loads: Homes with multiple HVAC zones, well pumps, pool equipment, workshops, or EV charging that require true whole-home power, not just a few “critical circuits.”
- New solar-plus-storage plans: For homeowners starting fresh with both solar panels and a battery system, the aPower S makes installation easy and efficient. As the battery accepts direct DC input from new solar arrays while still supporting AC connections, you may also start with storage first and add solar later.
- Maximizing solar value: The Global MPPT algorithm helps capture more usable energy from varied roof planes and orientations, converting daytime sun into evening energy reliability and bill control.
- Off-grid: For customers aiming to go completely off-grid, the aPower S is an ideal solution. By landing PV on the aPower S and AC coupling it with the aPower 2, you gain increased power, expanded capacity, and enhanced reliability.
- Whole-home backup expectations: Keep whole-home powered through outages with UPS-grade stability and seamless transfer.
- Challenging climates or grids: Suited to regions with frequent blackouts, extreme heat/cold, coastal exposure, or steep time-of-use pricing where reliability and peak-shaving matter.
- Room to grow: Scale from a single battery to multi-unit systems for very advanced use, such as families adding EVs, heat pumps, or additional living space, without redesigning the electrical plan.
- Design for longevity: Minimalist exterior, quiet fanless cooling, and a long-term warranty for homeowners who want equipment that perfectly fits into home environments and endures.
Final Thoughts
The aPower S retains the aPower 2’s core strengths in storing, protecting, and delivering electricity whenever you need it, while adding integrated direct-DC solar input and advanced Global MPPT algorithm to adapt to lighting conditions and maximize solar harvest.
If you’ve been looking for a home battery that keeps pace with the future of home energy, this is it.
