Tesla Energy Powerwall FAQs


Other than the actual Tesla Energy Powerwall, what else is needed?

You will need a compatible inverter.  The currently compatible inverters are the SolarEdge Inverter for single phase.

Maxx-solar is able to provide and recommend an installer for all the system requirements for your own personal needs including but not limited to, the Tesla Energy Powerwall, a compatible and appropriate inverter and solar panels.


Which inverters can be used with the Tesla Energy Powerwall?

Currently the SolarEdge (Single Phase properties) is the only one able to work in conjunction with the Tesla energy Powerwall in South Africa.


Will the batteries be reduced in price anytime soon?

After currency conversion, shipping costs to South Africa, South African import tax and duties, warehousing costs, freight costs and so forth, it is unknown if the cost is going to decrease anytime soon. However, should our Rand strengthen in the near future, this will play a part in decreasing the prices. At the moment we are already offering the Tesla Powerwall and compatible inverter at the most competitive pricing we can around South Africa.

Can Finance be arranged for the Tesla Energy Powerwall?

Kindly contact our Cape Town or Johannesburg offices to explore possible options under 021 813 9370.


How long has Maxx Solar been operational and what areas do we cover?

The maxx | solar energy group with headquarters in Thuringia in Germany provides its customers with all services related to photovoltaics, including the planning, construction and maintenance of residential, commercial or agricultural PV power plants. Through maxx | solar energy South Africa (Pty) Ltd., the maxx group extends it presence into South Africa. The service and product range of maxx | solar energy (Pty ) Ltd. includes consulting, planning, procurement, installations, maintenance and wholesale. As a long-time partner of German PV system integrator IBC SOLAR, the Thuringian company and its subsidiary in South Africa stand for the highest quality standards in photovoltaic technology. This quality standard has been integrated as a part of the certification by the RAL Quality Assurance Association and by TÜV Thüringen. The maxx I solar academy – an independent training centre for solar technology – was founded in 2011 together with the DGS Solar School Thuringia. The maxx I solar academy is represented by four branches in South Africa and has trained more than 700 participants.

Embedded generation / Off Grid

Can I sell my excess power to Eskom?

At the present moment in time there are two municipalities who are experimenting with this concept. Once we have had a successful trial run we are hoping that various municipalities and Eskom will be open to this idea for all residential and commercial properties


Is there any regular maintenance on the Tesla energy Powerwall?

No, unlike many other batteries available, the Tesla energy Powerwall does not require any monitoring or maintenance by the owner. In the unlikely event of any servicing or troubleshooting, a maxx I solar accredited installer will provide this service.


What are the details of the warranty for the Tesla energy Powerwall?

The Tesla Energy Powerwall come standard with a 10 year limited warranty (The first of its kind!).

The limited warranty covers defects in parts and workmanship. It also covers at least 60% energy retention after a 10 year period, provided it is registered and used within Tesla’s terms and conditions. By the end of the warranty, the Tesla Energy Powerwall will retain at least 60% of its initial energy capacity. The duration of time it keeps working past the end of the warranty is dependent on a variety of factors including type of operation and environmental conditions.


What is all the “Hype” about the Tesla Energy Powerwall?

The Tesla Energy Powerwall is a state of the art Tesla battery specifically designed for residential and light commercial applications. The Tesla Powerwall enables the storage of energy such as Solar Power.  The Tesla Energy Powerwall is used to store solar energy during the day for use in the evenings. Another feature of the Tesla Powerwall is that it can also provide backup power in case of a grid outage.

What is inside the Tesla Energy Powerwall?

The Tesla energy Powerwall contains lithium ion batteries, a DC/DC converter, liquid thermal control system, and a battery management


What are the dimensions and weight of the Tesla energy Powerwall?

Dimensions are 1300 mm (L) x 860 mm (W) x 180 mm (H). The Tesla Powerwall weighs about 100 kilograms.

Does the Tesla Energy Powerwall make any noise?

The Tesla Energy Powerwall is a silent battery system; however the packaging does contain a small fan as part of the cooling system. The fan itself is virtually silent and the noise level when the fan is in operation is less than 50dB.

Where is the Tesla Energy Powerwall manufactured?

The Tesla Energy Powerwall’s are manufactured in Tesla’s Gigafactory in Nevada, USA.

How much should a Tesla Energy Powerwall reduce my electricity bill? What is the payback period for Tesla Energy Powerwall?

There are a variety of factors influencing the savings that can be generated by using a Tesla Energy Powerwall, the electricity rate in your area, how your solar system has been set up among several other factors

How is the Tesla Energy Powerwall different to the other batteries that are currently available on the market?

In comparison to other batteries and battery systems on the market, Tesla Energy Powerwall, when paired with a compatible inverter is easy to install and setup. Unlike other battery systems the Tesla Energy Powerwall will continue to work seamlessly without any maintenance from the homeowner. The Tesla Energy Powerwall is also the most aesthetically pleasing battery on the market.

Is there more than one use for the Tesla Energy Powerwall?

Yes, you do not need a PV/Solar power system to operate the Tesla Energy Powerwall. The Tesla Energy Powerwall can be used for load shedding or backup power during grid maintenance. The Tesla Energy Powerwall can be charged using power from the grid or a generator.

Can the Tesla Energy Powerwall store any extra energy produced by my PC/Solar system?

Yes, if you have a solar system, the Tesla Energy Powerwall can store your excess energy for you to use at a later time.

If there is a power outage, will I be able to use my PV/solar system and the Tesla Energy Powerwall?

Yes, the Tesla Energy Powerwall will allow the PV/Solar system to continue functioning during a power outage as long as it paired with a compatible inverter capable of islanding. The PV/Solar system will supply power during sunlight hours and any excess energy will be stored in the Tesla Powerwall. When the PV/Solar system is not producing power, the Tesla Energy Powerwall will provide power to the essential loads.

Can I go completely go off-grid using the Tesla energy Powerwall and if so how many Tesla Energy Powerwalls would I need to do this?

Yes the Tesla Energy Powerwall can be used to go completely off-grid. You will need to make sure that you have a power generation source (a PV/solar system or a generator) that is attached to a compatible inverter.  At present the SolarEdge inverter does not support off-grid capability but Fronius does. The amount of Tesla Energy Powerwalls required to enable a person to have their property go off-grid will depend on the properties solar production and energy use. Should you be interested going completely off-grid please contact us.

How long can the Daily Cycle Tesla Energy Powerwall be used for? How many cycles does that amount to?

The Tesla Energy Powerwall is designed for day to day use. Specifically for the application of self-consumption of solar power and storage in the event of a power outage. If we assume full daily cycles, Tesla energy Powerwall is designed to provide energy for 3650 full cycles which is the equivalent to 10 years of use. We at maxx I energy would like to request that the term “cycle life” or “number of cycles” should be carefully used as some companies use this term while not necessarily referring to a complete cycle (0 –> 100% –> 0%).

Is it possible to connect more than one Tesla EnergyPowerwall together to increase power or energy?

Yes, you can connect up to 8 Tesla Energy Powerwalls in parallel to increase energy, power, or both. Unfortunately at the moment the inverters that are currently available are not able to support the integration of more than 2 Tesla Energy Powerwalls per inverter. The current downside to this is that while integrating 2 Tesla Energy Powerwalls in parallel it only increases the energy and not the power. A DC combiner box may be required for integrating multiple Tesla energy Powerwalls.


Does the system have Uninterrupted Power Supply (UPS) functionality? What is the switchover time to the Tesla energy Powerwall in case of an outage?

The switchover time and functionality of the UPS are reliant on the inverter. The inverters that are currently compatible do not support UPS function. The current inverters have 2 seconds switchover time.

Can I use any other inverters not on the Tesla approved list?

No. Using a non-approved inverter will void the Tesla’s warranty on the Powerwall.

Why is the Tesla Energy Powerwall compatible with only selected inverters?

For maximized efficiency and to make the installation process easier, the Tesla Energy Powerwalls are designed to connect to dual input port inverters that have a DC output voltage of 350-450V. Majority of existing inverters on the market are only compatible with batteries up to 48V nominal voltage. Tesla has decided to concentrate all their energy to partner with SolarEdge and Fronius but are currently evaluating several other inverters for compatibility.


Can the inverter supply the customer backup loads in the event of a grid failure? What capacity can be reserved for backup functions?

Yes. The SolarEdge solution requires a back-up panel.


When installing the new Tesla Energy Powerwall, what hardware is needed with a new PV installation?

On a new PV installation a Tesla Energy Powerwall compatible inverter will be used to serve the PV array and Tesla energy Powerwall. The only other factor to consider is the critical loads panel if backup power is required. The Tesla Energy  Powerwall itself does not require any additional hardware, however local installation codes may require additional hardware such as a DC disconnect switch.


Can the Tesla Energy Powerwall be integrated to an existing PV installation, or is it only meant to work on new installations?

Yes, the Tesla Energy Powerwall can be integrated into existing PV installations as well as new installations.


Operation & Software Control


How does it work to charged and discharged the Tesla Energy Powerwall?

The communication between the inverter and the Tesla Energy Powerwall determines when to charge and discharge. The instructions from the inverter communicate with the Tesla Energy Powerwall’s on-board Battery Management System (BMS) which in turn controls charging/discharging of the battery.

How is the status of the Tesla Energy Powerwall monitored?

The Tesla energy Powerwall is designed to be self-thinking meaning that the user e.g. doesn't have to switch the Powerwall on or off, everything works automatically. The great part is, that the Tesla Energy Powerwall and its status is visible on the monitoring software provided by the inverter.

Which modes can and cannot be programmed? How is the programming done?

The programming function allocated to the system varies from inverter to inverter and may also vary over time as various companies upgrade their hardware and firmware.

Can inverters be remotely controlled via various interfaces?

All approved inverters from SolarEdge can be controlled remotely.


To communicate with the Tesla Energy Powerwall - What are the communication interfaces and protocols available?

This communication is currently only available to the inverter and not directly to the Tesla Energy Powerwall. This takes  place via an API. Protocols vary from inverter to inverter.

Can a Solar system be configured to use the available solar generation to prioritise between charging the battery and supplying the required load?

Yes. The control modes allows for prioritizing load versus storage and vice versa.

What standard performance measurements of the system are available and what format are they available in?

Electrical parameters such as power, voltage, state of energy (SOE), and error codes are reported.

In the event of a communications outage, what is the automatic mode for the system?

The system will automatically revert to the most recent dispatch schedule in the event of a power failure.

Is the Tesla Energy Powerwall software updated?

The Tesla Energy Powerwall is sent software updates via the inverter’s internet connection.


Safety and Environmental


How safe is the Tesla energy Powerwall?

The Tesla energy Powerwall has been built from the ground up to deliver many levels of protection. The Battery Management System is very advanced and accompanied by a liquid thermal control system which ensures for the optimal battery functionality. All tests and certificates are up to date with market safety standards.

How does the Tesla Energy Powerwall maintain the safety of their batteries?

The Tesla Energy Powerwall itself provides the safety of its batteries – this is maintained by itself. The Tesla Energy Powerwall has an integrated Battery Management System that ensures the battery always functions in a safe manner.

Are the batteries inside the Tesla Energy Powerwall recyclable?

Yes, the lithium ion batteries recyclable. Furthermore, Tesla will accept the Tesla Energy Powerwalls for recycling at their Gigafactory


Must we be worried about any fire hazard when it comes to the Tesla Energy Powerwall?

No absolutely not. During the normal day to day operations of the Tesla Energy Powerwall there is absolutely no fire hazard to be worried about.