What is better than a Tesla Powerwall for a large home?
For a large home full of technology, a system built to condition power all day is usually a better fit than one built to store it. The two products are designed around different problems.
A Powerwall is an energy storage system. Its main jobs are to store solar energy and to back up the house when the grid fails. That is a good match for a smaller home with solar on the roof. A large home in Weston, Nantucket or Newport usually has a different list of worries: a network rack that can’t reboot during a video call, a theater processor that keeps dying, lighting control that loses its mind after a flicker, and a wine room that has to stay cold. Those are power quality problems as much as outage problems.
| Energy storage battery | RoseWater HUB | |
|---|---|---|
| Main job | Store energy, often from solar, and back up the house | Condition power continuously and back up the house |
| When the grid is up | Waits in standby | Carries the load and cleans the power 24 hours a day |
| When the grid fails | Switches over | No switch. Zero transfer time |
| Sags, surges and noise | Not its job, per RoseWater | Voltage regulation, noise filtering, surge and lightning protection |
| Service sizes | Varies by product and quantity | 100 A (HUB20), 200 A (HUB40), 208 V three-phase |
| Needs solar? | Usually paired with solar | No. Solar is optional, up to 10 kW |
| Battery chemistry | Usually lithium | Advanced lead-acid (carbon) |
How many Powerwalls does a large home need?
The number depends on your loads and on Tesla’s current specifications, which a Tesla installer can confirm. What matters more is that adding units adds storage and output, but not a different kind of protection.
Stacking several storage batteries can give a big house enough energy to ride out an outage. It does not change what happens on a normal day, when the batteries are waiting in standby and the grid’s sags and surges go straight through to the equipment. If your main frustration is equipment that keeps failing or rebooting, more storage will not fix it.
Does a Powerwall condition power or only store it?
Storage batteries are designed to store energy and back up the home. RoseWater’s position is that they are not built to condition power or stop sags and surges, and that is the core difference between the categories.
Conditioning means correcting the power before it reaches your equipment. A RoseWater HUB is always online with double conversion. Power comes in, is converted and rebuilt, and leaves as a clean 120 V, 60 Hz sine wave with total harmonic distortion under 3%. When the voltage sags, the batteries fill the gap. When a surge or lightning strike comes in, non-sacrificial protection rated for up to 40 strikes of 140,000 V takes it. Our How It Works page covers the full design.
Integrators who install HUBs see the difference in service calls. One New York integrator, Nick DeClemente of Elevated Integrations, compared service reports year over year after a Hamptons install and said “our service calls were reduced by 80%.” Results vary by home, but the pattern is common enough that RoseWater reports integrators seeing up to 95% fewer service calls.
Can a home battery back up a full 200 amp panel?
Yes. The RoseWater HUB40 provides 40 kW of continuous power conditioning on a 200 A service.
- HUB20: 20 kW on a 100 A service in one cabinet, 84 inches high. Good for a 100 A service or a subpanel of critical loads.
- HUB40: 40 kW on a 200 A service in two 52-inch cabinets that sit side by side or stacked. It won CEDIA’s 2023 Best New Hardware award, and an outdoor enclosure is available.
- 3-Phase systems: 30, 45 or 75 kVA on a 208 V three-phase service, for the largest homes.
The HUB20 and HUB40 start with 28.8 kWh of storage. The HUB20 expands to 86.4 kWh and the HUB40 to 172 kWh. 3-Phase batteries are sized per project. Homes larger than one HUB can carry use multiple HUBs in one design.
Do I need solar to use a Powerwall alternative?
You don’t need solar for a RoseWater HUB. It charges from the grid or a generator and does its full job without panels on the roof.
That matters in New England, where plenty of large homes have no good roof for solar, sit in historic districts, or simply have owners who don’t want panels. If solar comes later, a HUB accepts up to 10 kW through RoseWater’s SBX10 solar box. See battery backup without solar for more.
What RoseWater does differently
RoseWater started by studying how mission-critical facilities keep their power clean, then built that approach into a cabinet for homes. The company was founded in 2012 and installed its first HUB in 2015. The HUB has no transfer switch and no eco mode, its critical parts are hot-swappable from the front, and it has built-in remote monitoring with alerts that can go to the owner, the dealer and RoseWater. It uses advanced lead-acid batteries rather than lithium, which our battery chemistry guide explains.
How to choose
If you mainly want to store solar energy in a modest home, a storage battery is a reasonable choice. If you own a large home with serious technology in it, start with a list of what must never go down and let that decide. Our Power Plan tool builds that list in a few minutes, and our comparison page lays out the options. We design the system, coordinate your licensed electrician and RoseWater’s commissioning team, and support it afterward. You can also reach us directly.
