Tesla
Powerwall 3
11.5 kWContinuous AC
13.5 kWhOne base unit
185 AMotor start · 1 second
Full battery output from one base unit. Add battery-only Expansion units for runtime, or full Powerwalls for more power. Tesla specs ↗
Residential battery comparison
Two systems. Different ways to scale.
Tesla Powerwall 3 vs Canadian Solar EP Cube 2.0
What it costs
- Entryfrom $2,499 installedFridge, furnace fan, and a few key circuits, overnight.
- Valuefrom $5,400 installedWhole home overnight from one wall mounted bank.
- Premiumfrom $17,999 installedWhole home plus EV charging through an outage.
Four tiers on the battery page, each with its runtime.
See every priceFixed-size battery
Canadian Solar · Eternalplanet
EP Cube 2.0
11.5 kWAC · ≥15 kWh battery-only
5 to 40 kWhPer inverter system
185 AUp to · 1 second
Smaller energy increments, generator charging, and native EV integration. Small battery configurations have lower nighttime output. EP Cube specs ↗ Integration ↗
A 200A panel is not
a 200A battery.
a 200A battery.
At 240V, 200A represents 48 kVA of service capacity, not the home’s actual demand. One 11.5 kW system supplies roughly 48A at unity power factor. Whole-home connection still needs a plan for simultaneous loads, motor starts and outage duration. Tesla ratings ↗ EP Cube ratings ↗
Keep the roof. Check the battery connection.
Both systems support AC-coupled existing solar. Powerwall 3 does not require a working microinverter roof to be rebuilt as DC solar. EP Cube 2.0 also supports existing AC PV systems. Exact inverter model, settings and array size still matter. Tesla retrofit guide ↗ EP Cube Canada ↗
Existing roof DC → microinverters → AC house circuits → battery system’s built-in conversion stage → stored DC energy.
During discharge, the battery inverter converts stored energy back to AC. This is a conceptual energy path, not a wiring diagram.
During discharge, the battery inverter converts stored energy back to AC. This is a conceptual energy path, not a wiring diagram.
Tesla: check the AC-solar ratio
The published limit is 7.68 kW of third-party AC-coupled PV in the backup circuit per Powerwall without Expansion. Tesla uses the smaller of inverter AC rating or array DC rating. A qualifying Expansion configuration at the 11.5 kW power setting permits up to 10 kW AC-coupled PV. Expansion does not add inverter output. Exact limits ↗
EP Cube: verify the proposed topology
AC coupling is supported, but the current product page does not establish an APsystems model-specific approval or a battery-dependent AC-PV limit. The 24 kW figure is DC input, and 7.6 / 11.5 kW battery discharge ratings are not AC-solar input limits. AC coupling ↗ Rating definitions ↗
Will the solar run through an outage?
It depends on the approved backup arrangement and inverter response. Tesla describes frequency shifting to reduce or shut off third-party solar when generation exceeds what the loads and battery can absorb. Do not promise continuous roof production when the battery is full. Confirm the actual microinverter model and grid profile for either system. Tesla operating limits ↗
Which is better value?
Compare a 13.5 kWh Powerwall with at least 15 kWh of EP Cube if you want 11.5 kW battery-only output from either. Keep working roof equipment unless a documented constraint justifies changing it. A lower installed cost per kWh is not proof of a shorter payback; annual savings need household imports, exports, tariffs and battery losses. Tesla ratings ↗ EP Cube ratings ↗
Do not confuse input, output and storage. A 20 or 24 kW solar array rating does not mean that much AC backup power. LRA is a brief motor-start current rating, not sustained household power. Manufacturer expansion maxima below are not an Alberta installation approval.
What changes when the grid goes down?
Explore rated battery-only output and illustrative runtime. This model uses 240V, balanced loads, no solar and new batteries. It is not a CEC load calculation.
Build the two systems
Factor is an assumed allowance for losses and conditions, not a manufacturer efficiency. Runtime = nominal energy × (1 − reserve) × factor ÷ load.
Battery-only · no solar contribution
Backup headroom
200A service reference48 kVA
0240V × 200A · not measured demand
Power vs runtime
Tesla Expansion units add 13.5 kWh each, but no separate AC inverter. EP Cube modules raise battery-only power from 3 kW at 5 kWh, to 7.6 kW at 10 kWh, to 11.5 kW at 15 kWh and above. More modules beyond that extend runtime, not the inverter ceiling. Tesla ↗ EP Cube ↗
Manage the heavy loads
Illustrative demand: a 40A EV charger at 240V draws 9.6 kW, leaving only 1.9 kW on an 11.5 kW inverter before other loads. Reduce or suspend EV charging, electric heat and other discretionary loads during backup. EP Cube lists a 5.75 kW per-phase maximum; a total-power pass is not a phase-balance check. EP Cube ↗
Nameplate maximum configurations only. Tesla: up to 4 inverter units plus 3 Expansion units on the leader; EP Cube: up to 3 inverter systems. Equipment selection, interconnection, location, aggregate storage and load management need separate local design review. Tesla ↗ EP Cube ↗
Installed cost per stored kWh
Canadian dollars. Different evidence quality, shown explicitly. These fixed cost baselines are separate from the sizing simulator; edit them to compare actual quotes.
Powerwall 3 · 13.5 kWh
An earlier Raydn planning scenario, not an approved offer or current supplier quote. Assumes one Powerwall 3, gateway and a standalone battery installation. Before GST; equipment pricing, actual labour and site scope must be confirmed. The separate panel project is excluded.
EP Cube 2.0 · 15 kWh
No invented installed price. Raydn has a dated supplier component list, but the landed kit, required accessories, labour and retrofit arrangement need a current written quote. This comparison uses three 5 kWh modules for the 11.5 kW battery-only rating. Configuration ratings ↗
Match the scope first.
13.5 kWh and 15 kWh are not identical capacities, but both selected systems reach 11.5 kW battery-only output. Compare backup coverage, gateway, solar integration, commissioning, freight, warranty support and tax on the same basis. The simulator does not automatically reprice larger systems. Tesla ↗ EP Cube ↗
Cost model boundaries
Cost/kWh = installed total before GST ÷ nominal storage capacity. This is not lifetime energy cost or a payback forecast. No rebate, energy savings or bulk-system discount is assumed. New solar, generator, EV charger and major service reconstruction are excluded unless the entered quote includes them. Inputs stay in this browser tab and are not sent anywhere.
Source register & reading notes
Manufacturer specifications take priority over reseller comparisons. Technical basis: North American split-phase models; Canadian Powerwall warranty. Checked September 22, 2026.
Important interpretation notes
Continuous output is not surge output
185A LRA describes motor-start capability for one second. It is not a continuous 185A supply and is not converted here into a peak-kW claim. A comparable separate peak-kW rating is not provided in the cited tables.
Tesla’s 15.4 kW rating is conditional
The current Tesla North American table explicitly labels this “off-grid (PV only, −20°C to 25°C).” It requires the 11.5 kW configuration and installation conditions in Tesla’s manual. The dashboard does not treat it as nighttime battery-only power. Read the exact table ↗
EP Cube’s charge and discharge rows differ
The V1.4 table lists 3 / 5 / 6 kW battery charging for 5 / 10 / ≥15 kWh, but 3 / 7.6 / 11.5 kW battery discharge at 240V. The original PDF table was visually checked because flattened text extraction can mix these rows. The LRA row is “up to 185A”; verify actual motor-start performance for the ordered small-stack configuration. Original table, page 3 ↗
Warranty comparison is region-specific
Tesla’s Canadian warranty effective June 20, 2025 specifies 80% retention, not the 70% often quoted elsewhere. EP Cube’s terms here are the North American datasheet summary, not an assertion that every contractual exclusion is identical. Obtain the Canadian sales warranty with the equipment order. Tesla warranty ↗ EP Cube summary ↗
Alberta installation is a separate design gate
200A identifies the service/panel context, not actual demand or storage permission. This dashboard makes no CEC compliance determination. Manufacturer scaling ceilings are not a promise that the maximum storage configuration can be installed at a particular home. Review actual loads, motor starts, phase balance, winter temperature, siting, gateway compatibility and local requirements before quoting.