Tesla Powerwall vs. FranklinWH: Which Backup Battery Fits Your Home?
Updated August 2026 with the latest rates and program details from PURA, Eversource, and state program filings.
Thesis: Powerwall 3 and FranklinWH aPower 2 are both elite batteries — the right choice comes down to whether you're optimizing around solar conversion or whole-home capacity and expansion. We install both, so here's the spec-sheet-honest comparison.
Tesla Powerwall 3
13.5 kWh of usable capacity with a strong 11.5 kW of continuous power — enough to start and run heavy loads like well pumps and AC. Its standout feature is the integrated hybrid solar inverter with 97.5% round-trip efficiency, meaning solar panels can connect directly to the battery without a separate inverter, simplifying the system and squeezing more usable energy from every ray of sun. It uses safe lithium iron phosphate (LFP) chemistry, and installed pricing in 2026 typically runs $13,500–$16,500 depending on the home. The app is the most polished in the industry.
FranklinWH aPower 2
Bigger per unit: 15 kWh of capacity with 10 kW continuous and 15 kW peak output, also LFP chemistry, rated to operate from −4°F to 131°F — a real consideration in a New England winter. Its aGate controller is a true whole-home energy manager that integrates cleanly with generators, and the system scales to a massive 225 kWh across 15 units. It carries an industry-leading 15-year warranty (most competitors, including Tesla, are at 10), with typical installed pricing around $17,500 for the first unit.
Don't skip the program money — in either state
In Connecticut, the Energy Storage Solutions program pays homeowners performance incentives for letting their battery support the grid at peak — under the framework effective April 2026, program materials cite up to $1,500–$2,750 per year in the first five years for a typical home battery. In Massachusetts, the ConnectedSolutions program pays $275 per average kW delivered during summer peak events — commonly working out to around $1,000–$1,500 a year for a well-sized battery. Either program meaningfully changes the payback math.
How we help you choose
We look at your usage, your outage history, what needs to stay on when the grid drops, and your budget — then design around the answer, not around one manufacturer's catalog. That's the advantage of installing both.