Panasonic EverVolt Vs. Tesla Powerwall Battery Comparison
Panasonic has worked with Tesla to supply their batteries since 2009. However, this long-time relationship may be coming to a close.
In March of 2021, Panasonic sold its shares in Tesla. Although it still has a supply agreement until 2030, Tesla has now turned to other battery manufacturers, like CATL.
Because of the close relationship of these companies, their battery options should come close. However, the truth is that they’re some differences.
The Differences Between AC and DC Batteries
Batteries store direct current (DC). An inverter switches DC to alternating current (AC), so it’s usable in the house. Once in the home, a rectifier, often in power cords, changes the current back to DC, so it can power household gadgets.
Each time the electrical current switches between AC and DC, some energy loss occurs. AC-coupled batteries require the current from the solar panels to invert from DC to AC and back to DC before storing electricity. When ready to use it, the battery then switches the current back to AC, decreasing efficiency with each transition.
DC batteries have a power optimizer or hybrid inverter that transfers the DC from the solar panels to the battery. Then when needed, an inverter transforms the current to AC for household use. While slightly less efficient, AC batteries can connect with a wider variety of preinstalled solar arrays, making it easier and cheaper to add energy storage.
Powerwall 2: An AC-coupled Battery
The Powerwall 2 is an AC-coupled battery. It claims 90 percent round-trip efficiency.
EverVolt AC and DC Batteries
Panasonic has both DC and AC versions of the EverVolt. The DC version has 89 percent round trip efficiency, while the AC battery has 84 percent.
Comparing Charge Capacity and Maximum Power Rating
Two factors that help customers determine which battery to purchase include the charge capacity and maximum power rating. The charge capacity tells them how much power the battery can store. The maximum power rating indicates the max discharge rate. Together these two factors determine battery usability, which helps customers better compare battery options.
Tesla Powerwall Capacity and Max Power Rating
The Tesla Powerwall has a capacity of 13.5 kWh and a max power rating of 5kW. These numbers mean a fully charged Powerwall can provide 13.5 kWh of power at a rate of 5kW per hour.
While one Powerwall will only power a few essentials, up to six Powerwalls can stack in the same system. Most homeowners can power all their needs with either two or three Powerwalls.
Panasonic EverVolt Capacity and Maximum Power Rating
Both the AC and DC versions of the EverVolt have the same capacity and maximum power ratings. Each battery type has standard and plus models. These models have between 11.4 -17.1 kWh capacity and 4.4 – 5.5 kW of maximum continual power.
Up to two Plus EverVolts can stack with one Panasonic inverter. While impressive, the EverVolt base model still stores and discharges less electricity at once than the Powerwall 2.
Home Battery Warranties
A quality warranty can make all the difference. Typically battery warranties last about ten years. Discover the warranty coverage that Tesla and Panasonic offer below.
Tesla Home Battery Warranty
Tesla offers a 10-year limited warranty and 70 percent of the guaranteed charge capacity. Unlike other battery warranties, the Tesla warranty doesn’t have a set number of cycles it will cover, which means homeowners don’t need to stress over how often they use their battery.
Panasonic Home Battery Warranty
Panasonic will guarantee up to 60 percent of the charge capacity for the lesser of ten years or 7.56 MWh per module. While this technically is within the industry standard, it isn’t as good as the Tesla warranty.