How the Tesla Powerwall Works
Inner Workings of the Powerwall
There are four main components in a Powerwall. These include the connection point, active liquid thermal controls, battery inverter and the battery module. Together, these components make on-demand solar power a reality for many solar homeowners.
The Importance of the Connection Point
The connection point is the point were the Powerwall connects to both the home and the solar array. It is the channel for the battery to charge and discharge through.
Active Liquid Thermal Controls on the Powerwall
Batteries tend to get hot when used. Ever use a laptop for a couple of hours and then felt the bottom of it while putting it away? It gets pretty warm.
A larger battery powering a home produces even more heat. To prevent the battery from overheating, cooling-liquid regulates the temperature.
Batteries typically produce direct current. The current going into, and out of, the battery switches to alternating current with the help of an inverter.
The Powerwall is a lithium-ion home battery. The ions in the battery move across it, which generates an electric current while it charges and discharges the battery.
Tesla Powerwall Features and Specs
- Total Energy: 14 kWh
- Usable Energy: 13.5 kWh
- Max Continuous Power: 5 kW
- Peak Power: 7 kW for 10 seconds
- Round-Trip Efficiency: 90 percent
- Dimensions: 45.3in x 29.6 in x 5.75in
- Weight: 276 lbs.
- Mounting Types: Floor and wall mount
- AC Voltage (Nominal): 120/240 V
- Internal Battery DC Voltage: 50 V
- Grid Frequency: 60 Hz
- Amps: 30 or less
- Warranty: 10-year limited warranty
Use power whenever you need it, even in an outage.
Why Lithium-Ion Batteries Are More Widely Used
Lithium-ion and lead-acid batteries are the two main battery types used for solar energy storage. Home batteries are typically lithium-ion.
Lead-acid batteries are cheaper, but they are also heavy, have a low depth of discharge, and a shorter lifespan. Not only is this battery clunky but, in the long run, it won't perform as well, which is why Tesla uses a lithium-ion battery for its home battery.
While there are pros and cons to lithium-ion batteries, the application of this technology has increased over the years, which has spurred continued research and development of this battery type. Some of the reasons why this battery is preferred are its high energy density, low self-discharge, low maintenance, cell voltage and that they are ready to go without priming.
Powering Your Home With Powerwalls
Because the average Powerwall produces about 5 kW of continuous power, at least two Powerwalls are recommended for the average house. However, how many home batteries are needed depends on the electricity usage of your home and the desired electricity offset.
Although two homes may use the same amount of energy, the storage needs of the homeowner may be different. Homeowners that want to power their entire home during an outage will need more storage than someone that only wants to power a couple of essential appliances. Both of these homes would need less storage capacity than an off-grid home.
What Sets the Powerwall Apart?
The three main home battery competitors on the market include Sonnen, LG and Tesla. All of these competitors have high-quality home batteries. However, some features make the Powerwall stand out in the crowd. Two of these features include its built-in battery inverter and the monitoring app.
The Powerwall's Built-In Battery Inverter
Tesla has partnered with Panasonic, which is known for its high-quality products — meaning these batteries are well designed. One of the well-designed features of the battery is the battery cooling technology used to keep the battery temperature regulated.
Increased Functionality With the Gateway App
The Tesla Powerwall also has a robust management system. This system allows the customer to see how well the battery is performing and control when they want to use the stored energy in a sleek and intuitive app. This app is especially useful for time-of-use solar customers because they can schedule the Powerwall to run during the times of the day and week where energy costs the most.
Learn More About the Tesla Powerwall and Battery Backup
If you would like to learn more about how home batteries and other battery backup options fit into solar, check out one of our many blog posts covering these topics.