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What is Tesla Powerwall 2?

Tesla Powerwall 2 is a rechargeable lithium-ion battery system designed for home energy storage. It is intended to store excess energy generated from renewable sources like solar panels, allowing homeowners to use that stored energy during times of high demand or power outages.  This integration allows for greater energy self-sufficiency and potentially reduces reliance on the grid.

 

How does Tesla Powerwall 2 work?

Powerwall gives you the ability to store energy for later use and works with or without solar. Each Powerwall system includes at least one Powerwall and a Backup Gateway, which provides energy monitoring, metering, and management for the system. The Backup Gateway allows you to ‘island’ yourself from the grid either during a power outage or manually through the app. It can provide 32A of output power which allows running of all household appliances including Daikin Heat Pumps during a power outage too. The Backup Gateway also learns and adapts to your energy use over time and will continue to receive over-the-air updates allowing Powerwall to keep improving after it is installed.

 

What is the capacity of Tesla Powerwall 2?

The Tesla Powerwall 2 has a total energy capacity of 13.5 kilowatt-hours (kWh). This capacity is sufficient to power essential appliances and provide backup power during outages for most homes. Powerwall has the capability to charge and discharge simultaneously, meaning it can keep itself topped up during off-peak tariff hours whilst it powers your home.

Powerwall is charged by solar during the day, when solar panels are producing more electricity than the home is consuming. Powerwall then stores that energy until the home needs it, such as when solar is no longer producing at night, or when the utility grid is offline during a power outage.

The next day when the sun comes out, solar recharges Powerwall so you have a cycle of clean, renewable energy.

If your electricity rates vary throughout the day, Powerwall will charge when electricity costs are low and discharge when electricity costs are high, generating automatic savings. Powerwall will also provide backup power by detecting grid outages and automatically becoming the home's main power source.

 

Can Tesla Powerwall 2 power an entire home?

Depending on your electrical set-up, Powerwall will backup all your appliances (whole home backup) or essential loads (partial home backup). Powerwall provides 5 kilowatts of continuous power, which is typically sufficient to provide whole home backup during a grid outage.

With partial home backup, you can select which loads are essential such as lights and outlets. If your home runs on a three-phase power supply, Powerwall will support the appliances on a single phase that it is installed upon. Subject to G99 approval, you may be able to export from Powerwall which will allow further savings through net-sum metering. This can send power back to the grid on a different phase that is drawing energy which essentially cancels out any input energy you are importing from the grid.

While one Powerwall is sufficient to power a typical home in Great Britain, multiple Powerwall systems will allow you to back up more loads and keep your home powered during longer outages—with increased power output and overall capacity. Powerwall systems can be mounted side-by-side on a wall or floor or stacked front-to-back on the floor.

How long can Tesla Powerwall 2 provide backup power during an outage?

The duration of backup power provided by the Powerwall 2 during an outage depends on various factors, including the power demand of the home, the amount of stored energy in the Powerwall, and the energy consumption during the outage. For most homes, the Powerwall 2 can provide several hours of backup power.  Pair with solar and recharge with sunlight to keep your appliances running for days. 

A typical LED downlight will draw around 15W to run. If you had 5 per room over 5 rooms in your home, that would be 375W of energy.  Keeping all these lights on for 1 hour during a power outage would draw 0.375kWh of energy.  Assuming your Powerwall was 100% charged at the time of the power outage, Powerwall’s emergency backup power would keep the lights on for 1.5 days.

 

Is Tesla Powerwall 2 compatible with off-grid systems?

While the Powerwall 2 is primarily designed for grid-tied systems, it can also be used with off-grid systems when combined with other components such as solar panels, inverters, and charge controllers. Off-grid setups require careful system design to meet energy demand and provide sufficient storage capacity.

 

What is the warranty period for Tesla Powerwall 2?

Your Tesla Powerwall system offers a 10 year Tesla End User Warranty provided a physical Ethernet connection or Wi-Fi connection exists between the Tesla Powerwall and the property router. This will enable Tesla to undertake automatic monitoring and maintenance of the unit remotely. The Tesla Powerwall, once installed, will have 2 years labour and workmanship Warranty supported by The Natural Energy Company.

 

Where would I install Powerwall?

Powerwall easily endures outdoor temperatures ranging from -20°C to 50°C* thanks to its unique onboard thermal management system, and is IP67 rated, making it one of the only batteries on the market that can be installed outdoors.  Water cooled, and designed in conjunction with Tesla vehicles, Powerwall can keep the battery at the perfect temperature to ensure optimum operation.  Safety is one of our biggest priorities for all our installations and is one of the reasons we only offer Powerwall.  For added reassurance, the Tesla Powerwall comes encased in a fireproof box that can contain a fire for 30 minutes allowing adequate time to safely escape.  Many home insurers will are unable to offer cover if you have battery storage within your home.  Powerwall would be stored either on an external wall, or within your garage provided it is separate from the home or fire lined with with smoke and heat alarms.

To optimise performance, avoid installing Powerwall in locations exposed to direct sunlight or subject to extreme temperatures.  When Powerwall is exposed to temperatures outside of its optimal range of 10°C to 30°C, it may limit charge or discharge power to improve battery lifespan.  Additionally, while humidity and rain do not pose a risk, Powerwall should not be installed in locations subject to flooding or near water sources such as drainpipes or open drains. In order to maintain proper ventilation, Powerwall should be kept clear of debris such as leaves and dense bush.  At your survey we will work with you to agree the best location for your new Powerwall.

 

Can I add Powerwall to my existing Solar PV array?

Yes, the Tesla Powerwall 2 can be retrofitted into an existing solar power system. It can be integrated with your current solar panels and inverter to store excess energy generated during the day for later use. The Powerwall 2 works seamlessly with both new and existing solar installations.  It Is worth noting that when installing Powerwall on its own, you do incur a VAT charge at 20%.  When installed alongside a Solar array, you benefit from Powerwall being VAT Free.

 

What maintenance is required for Tesla Powerwall 2?

The Tesla Powerwall 2 requires minimal maintenance. It is designed for long-term reliability and performance. Regular software updates can be performed over-the-air, ensuring the system remains up to date with the latest features and improvements. Additionally, basic visual inspections to ensure proper ventilation and cleanliness are recommended.

 

What is time-based control?

Time-based control is a Tesla unique feature which allows you to connect to a tariff that enables you to benefit from off-peak tariffs. As mentioned in earlier questions, this is quite common however what isn’t is how Tesla controls it. The common issue with solar is you want to make sure you capture as much energy as possible. This is either by the house using it, or your battery storing it. If the house isn’t needing all the energy, and battery is full, the energy will go to the grid. You may get paid a small amount for this, but it will never be equal to what it costs to import the energy. Time-based control knows what you use daily, when you use it, and how you use it. One further step though is that it knows the local weather, for your location, 24 hours ahead. This means Powerwall can predict how much energy you will need to charge off-peak, to ensure when the solar comes on, it doesn’t fill up your battery and start exporting. This is a totally unique and game changing feature which takes away the battery storage element and turns Powerwall into an energy management system for your home. This is the same method Storm Watch uses to determine when to charge up fully in case you have a power failure.

What makes The Natural Energy Company a Premium Installer?

We’re very lucky to hold this status, something we are all very proud of. Our company exclusively offers Powerwall, installs them to a high standard, has very little issues during or after the installation, supports our customers, and shares sustainability goals with Tesla. All this means we can offer the best possible product, at the highest standard installation, for the best possible price.

Why should I choose Powerwall over other battery storage on the market?

With a 13.5kW battery, the Tesla Powerwall is one of the larger batteries on the market which creates more room to save your energy or top up that cheaper energy. While this is a definite advantage of having a Tesla Powerwall, many of its benefits are not contained in its box but rather in what we like to call the brain of the Tesla Powerwall, the Gateway. Along with the ability to top up and learn how you use your energy; the Tesla Powerwall also has the Storm Watch feature. This is quite clever and keeps an eye on the weather for you. If there is a storm approaching, then your Tesla Powerwall will ensure you are fully charged in the event of a power cut and keep your electricity flowing.

We believe that there is no comparison of the Tesla Powerwall with any other batteries that are currently on the market based on ways to save money, control your energy usage and, the most important things, safety. We have exclusively partnered with Tesla because we believe in the product, we trust it, and it works. 

What are G98 + G99 DNO Applications?

A Distribution Network Operator (Or DNO) is a company licensed to distribute electricity in the UK. These companies own and operate the system of cables and towers that bring electricity from the national transmission network to our homes and businesses. In Scotland this is typically SSE or Scottish Power. 

A G99 or G98 are the applications for permissions that are required by the DNO to connect your Tesla Powerwall to the grid.  We can manage this with you to ensure that the application is applied for correctly.   Once the offer of connection has been received from your DNO, they will advise if there are any restrictions to the proposed install such as required export off or restricted, or any additional upgrade required and the associated costs.  The Tesla Powerwall is set to non-export as standard.  The export feature of a Tesla Powerwall allows you to export the energy to the grid. Some energy plans require this feature to be turned on to gain access to the preferential rates. Non-export means that your battery can’t export to the grid once full.

No work will be carried out without consent from you. We are happy for you to handle the DNO approval, alternatively, we offer this service to deal with the process on your behalf with an administrative charge of £200 +VAT.