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Is the Tesla Powerwall 2 worth it?

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The Tesla Powerwall 2 is the most popular and cost-effective home storage product on the market, but is it worth the investment? 

The Tesla Powerwall 2 offers a range of functionality:

  • Storage of excess solar energy.
  • Up to 13.5kWh of backup in a power cut.
  • Off-peak charge and peak discharge.

So let’s look at the details…

Storage of excess solar energy

By storing excess electricity generated by your solar panels during the day, you can use that electricity during the evenings or on days with poorer weather. This reduces your electricity bills by minimising the amount of electricity your home needs to draw from the grid.

Up to 13.5kWh of backup in a power cut

Powerwall automatically becomes your home’s energy source when there is a power cut. The Tesla Powerwall 2 can be installed to back up the whole house, or it can be installed so that it backs up only certain loads. Even with ‘whole house’ backup, certain large loads (such as a spa pool) can be excluded to make your stored power last longer.

Not only will a backup-enabled system keep the lights on in a power cut, but it will also keep the solar system functioning. The system will continue to function whilst there is either a load or sufficient spare battery capacity to store any solar electricity it produces. The system will switch seamlessly and automatically.

You will need to specify a reserve percentage (e.g. 30%) and the system will always keep that percentage of the capacity in reserve for a power cut. These settings are easy to change.

Off-peak charge and peak discharge

More energy retailers are offering time-of-use (ToU) tariffs, with time-banded tariffs, reflecting demand and supply and the true underlying cost of electricity. With the advent of smart meters, able to record half-hourly electricity use, the market will continue to see more time-banded tariffs reflecting demand and supply. Clearly, there are large savings to be made by buying electricity at night and using it during the day. 

Powerwall’s time-based control allows you to input your different electricity rates so that it can make intelligent decisions about when to charge and discharge in order to save you the most money.


Tesla Powerwall

We recommend Tesla Powerwall 2 for several reasons:

Design and efficiency. The system uses a highly efficient battery and inverter (>90% AC in to AC out) combined with a battery management system controlling the state of charge, voltage, temperature and other parameters.

Quality control and safety. The system has been developed in-house by Tesla following their substantial experience in automotive battery technology. Every system undergoes extensive testing and inspection in their Gigafactory in the U.S. and the in-built management system incorporates an inherently multi-layered safety system.

10 year warranty. Unlike most battery manufacturers, Tesla prefers to talk in terms of years rather than cycles, cycles being a less easily understood concept than years. Tesla’s warranty guarantees unlimited cycles for self-consumption and time-based control (grid charging). The warranty guarantees the battery will retain 70% of its initial capacity after 10 years.

Beautiful design, wall hung and weatherproof. Space is a consideration in residential properties, as indeed is aesthetic appearance. The design is modern and minimalist, designed to be seen, not hidden away out of sight. And the waterproof case means that it can be installed outdoors.

Flexibility. Tesla has designed a system that will allow AC-coupling with any PV system, or even without a PV system if used only for off-peak charging and backup. Furthermore, up to ten Powerwall 2 units can be installed together to help power systems of varying sizes.

High capacity (kWh) and power output (kW). Powerwall 2 has a total usable capacity of 13.5 kWh and a maximum power rating of 5kW.

Grid backup facilities. Powerwall 2 enables you to continue providing power to your home or business during power cuts.

Control From Anywhere. Manage your system from anywhere in the world with 24/7 mobile monitoring.

If you are interested in installing solar panels or batteries then fill out the form below and one of our team will get in touch with you to see how we can help.

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