The first question everyone asks about a home battery is not whether it works — it is what it actually costs to get one on the wall. The honest answer is that the sticker price you see in a brochure is only about two-thirds of the real number. The rest is labor, permits, and the electrical work nobody mentions until the quote lands.
Every storm season, the same question lands in my inbox: should I buy a home battery or a standby generator? People usually expect a brand recommendation. What they actually need is a decision about how their house fails — and the answer changes completely depending on whether your outages are two hours or two weeks.
A customer called me last winter, frustrated. He had bought four 12V 100Ah deep-cycle lead-acid batteries, wired them for 48V, and connected them to a 5,000W inverter. His plan: power the furnace, fridge, lights, and router through a 2-day outage. The math on paper said he had 4.8 kWh of usable capacity, and his daily critical load was around 4.5 kWh. He should have had just enough to scrape through 24 hours.
Tesla is the default answer. Someone hears “home battery” and thinks “Powerwall” — the same way people used to say “Kleenex” for tissues. That brand recognition is earned. The Powerwall 3 is a genuinely good battery: 13.5 kWh, 11.5 kW continuous output, integrated inverter, clean industrial design, and the Tesla app experience that the rest of the industry is still chasing.