The Tesla Powerwall 2 is an efficient and attractive battery storage solution for your home.
Tesla first introduced the Powerwall in 2015. At the time production was limited, but several years later there are now over 200,000 units that have been installed globally.
But what exactly is the Powerwall and how does it work?
The Powerwall is a rechargeable battery system that is installed with solar power on your home. The excess energy you would normally send back to the grid throughout the day as your panels are producing is instead stored in your battery.
This stored energy is then used for a variety of things:
To power your home overnight when there is no solar being produced and reduce your reliance on grid energy.
To ‘top up’ your power throughout the day if you are using more than the solar is producing (meaning you won’t be pulling energy from the grid).
To provide continuous power in a black out.
Once the energy stored in the Powerwall has been depleted, it will recharge the following day from your solar power.
The Tesla Powerwall 2 has a storage capacity of 13.5kW, which is generally a suitable size for standard homes. This will run most standard loads - lights, power points, small appliances – along with larger loads for air conditioners, cook tops, dryers, hot water systems, pool pumps and even to charge Electric Vehicles (EV).
It’s important to note that the more appliances running, particularly the high energy appliances listed above, the faster the stored power will be used and to take this into consideration when choosing your battery storage solution.
For homes and businesses with a higher usage, the great thing is you can maximise your storage with up to 10 units installed.
This does have to be approved by the grid provider and for an application of this size, Ergon would need to perform a technical assessment prior to approving, which usually involves a fee payable to them.
I’ve already got Solar Power. How easy it is to add a Tesla Powerwall 2?
The great thing about the Powerwall is its compatibility.
Many home battery systems require the addition of a hybrid battery inverter, which means quite often you have to replace your existing solar inverter. While for some this might be the better option if you have an older inverter, or are interested in a different storage option, others may be wanting a more seamless transition.
The Powerwall has its own battery inverter built into it, eliminating the need for an additional hybrid inverter. This means it can be connected to an existing battery-ready solar inverter without the need for additional hardware to make it work.
Battery compatible inverters are already on the market, so it’s definitely worth talking to your Solar Installer to see whether the inverter you currently have, or are looking at getting, is compatible with a Tesla if that is the battery you are thinking of having installed.
I like to monitor what my system is doing. Am I able to do this with my Tesla?
Tesla are known for their ever-advancing technology. The Powerwall can be connected to your home WIFI and monitored through the Tesla App and website. Through the monitoring portal you can view the power flow and charge level, product details such as serial numbers and software versions. By having your system online, it will allow remote software updates to be applied as necessary.
It also does allow you to modify some of the settings, however these will be configured correctly while your accredited installer is on site and we recommend to avoid changing them as it can impact the system’s performance.
What do I need to do in a blackout?
When the grid power goes offline, the Powerwall with instantly disconnect from the grid and restore power to your home, effectively continuing as an ‘off-grid’ system. This will keep your appliances running without interruption. It’s so fast you might not even notice the back-up kick in and you won’t need to reset the clocks!
After five minutes with no grid connection, the Powerwall will notify you via the Tesla App so you are aware you are running on your back up energy supply and may need to adjust your household usage. When the grid comes back on, you’ll receive another notification.
Many solar and battery options don’t offer this complete back up. The inverter requires the grid supply to produce solar so while the grid is down, no power can be produced to power the house or recharge a battery. Once you have used the stored energy in the battery, you would have to wait for the grid supply to come back on and your solar to start working again.
One of the appealing things about the Powerwall is the ability to recharge the battery even when there is no grid supply. It will keep the solar running throughout the day without the need for the grid. Any power you aren’t using directly in your household will go back into the battery.
It’s important to be mindful that when in a black out and if it does span for prolonged period (for example a Cyclone hits and the power is out for several days), that the solar and Powerwall is powering your home day and night so to avoid depleting the saved energy throughout the day if you wish to have power overnight.
What happens to the excess power if my battery is already fully charged?
Many people aren’t home during the day so a significant chunk of their solar power is sent back to the grid for Solar Credits.
While we strongly recommend using your solar power during daylight hours – setting timers to run high energy appliances like washing machines, dryers, dishwashers, pool pumps – if you aren’t using all the solar you are generating, it will go back to your battery first. Once the battery is fully charged, any excess for the rest of the day will be exported back to the grid and the applicable Solar tariff rate applied.