Tesla Powerwall 2
The Tesla Powerwall is a rechargeable lithium-ion battery stationary home energy storage product manufactured by Tesla Energy. The Powerwall stores electricity for solar self-consumption, time of use load shifting, and backup power.
Tesla released its residential Powerwall 2 solar batteries in 2016. These batteries use a common Lithium Nickel Manganese Cobalt Oxide chemistry and the Powerwall 2 features a Total Capacity of 13.5kWh and a Usable Capacity 13.5kWh.
The Powerwall 2 has a storage capacity of 13.5 kilowatt-hours (kWh) given it is coupled with a solar array that has adequate sunlight and production capabilities. The Powerwall 2 is able to provide a full day’s energy back up during cloudy conditions or low/limited light on winter days. During the bright summer, the Powerwall 2 may power your home for up to 2.5 days.
A system serviced by two Powerwall 2s may result in an additional 12 hours during low light conditions. On sunny days, adding a second Powerwall 2 may allow an additional 72 to 96 hours of capacity. To go off grid permanently, the average Texas home would require 3 or more Powerwall 2 batteries. Tesla allows you to connect a maximum of 10 Powerwall 2s in a single residential storage system.
The Powerwall 2 has a roundtrip efficiency rating of 90% with 3% degradation.
Round-Trip Efficiency
In order for a battery to function, a small amount of electric power is required for its operation. The total amount of charge that comes out of a battery subtracted from the amount of charge that went into the battery is expressed as a percentage ('%'). This is called Round-trip Efficiency. The U.S. Energy Information Administration, assesses average round-trip efficiency at approximately 80%. The Tesla Powerwall 2 demonstrates a round-trip efficiency of 90%, well above average.
The Powerwall 2 can operate continuously at 5.8 kW, with 10 kW possible in short bursts.
Continuous power is a measurement, expressed in kW, of a battery's potential to release a sustained energy for a given period. Peak power is a measurement, expressed in kW, of a potential maximum power output in short bursts. The Powerwall 2 provides 10 kW of peak power and 5.8 kW of continuous power.
The Powerwall 2 has a roundtrip efficiency rating of 90% with 3% degradation.
WARRANTY
Tesla backs the Powerwall 2 with a 10 year unlimited through cycle warranty. Tesla also guarantees at least 70% of capacity at end or warranty term.
The Powerwall 2 comes with a 10 year, unlimited cycle warranty and a 4-year workmanship warranty covering any repairs, replacement parts, shipping, and installation related issues. Tesla guarantees the Powerwall 2 will have 70% of its original 13.5 kWh capacity, at the end of the tenth year. Tesla offers what may be the strongest battery warranty available in 2023.
The Battery Dimensions are 1150.0 mm L, 755.0 mm W, 155.0 mm D.
System Compatibility
The Tesla Powerwall 2 is compatible with most common solar inverters brands on the market.
Solar Battery Metrics
| Manufacturer | Tesla |
| Model | Powerwall 2 |
| Capacity | 13.5kWh. |
| Chemistry | (NMC) Lithium Nickel Manganese Cobalt Oxide |
| Depth of Discharge | 100% |
| Round Trip Efficiency | 90% |
| Monitoring | Tesla Powerwall Gateway |
| Cooling | Liquid Cooling |
| Dimensions | 1150.0 mm L, 755.0 mm W, 155.0 mm D |
| Weight | 114 kg (251.3 lbs) |
| Warranty | 10 year, unlimited cycle warranty |
- PRO-10-year warranty with unlimited cycles
- PRO-70% capacity guaranteed at the end of the warranty
- PRO-Five-year warranty extension as optional upgrade
- PRO-Seamlessly integrates with Enphase inverters
- CON-Only available in a single 13.5 kW size, limiting customization
Notes:
| Solar Batteries Configuration | |
|---|---|
| Cooling | Liquid Cooling |
| Dimensions LxWxH | 1150.0 mm L, 755.0 mm W, 155.0 mm D |
| Manufacturer | Tesla |
| Warranty | 10 year |
| Weight | 114 kg |