TESLA Lithium-ion (Li-ion) Batteries
NB: Tesla Li-ion battery technology has been superseded by the Safer LiFePo4 battery technology !
This is a great video that explains the issues with recycling Lithium-ion battery’s. Note, Lithium-Iron is different technology.
So what should you know about the latest Tesla Powerwall 2.0 ?
The latest Powerwall is now said to provide 13.5kWh backup power, in the event of a blackout this battery system is designed to store electricity generated from rooftop Solar Panels Only, it has an inbuilt inverter, and is not ideally suited for importing power from Aqua, Wind or Diesel Generators, for that reason we recommend LiFePo4 or NiFe or RedFlow Battery's as they are !
You can load shift (draw electricity from the state power grid to charge the battery), usually this is done slowly at night when rates charges are low, to store for later use.
It’s reported that, “Panasonic makes the cells for the Powerwall, while Tesla builds the battery module and pack”.
The new Powerwall 2.0 also comes with a design update and is Casing is more rectangular and flatter than the previous generation, the Powerwall 2.0 weighs 122kg (269lbs) making a Solar Only installation simpler and easier.
The Powerwall 2.0 units has a 13.5kWh battery and a new modular design and a price that's reasonably affordable at approx. $660 per kWh (excluding installation), the inbuilt inverter, making for a cheaper and simpler installation, But unfortunately no so good for clients that want to utilise Other forms of power harvesting!
However, what is not widely advertised is the facts that, "the investment cost for ALL small to large scale micro power grids", are able to be self funded based on energy savings alone, from 4~6+ years when using DAT Solar Arrays !
- Usable Capacity 13.5 kWh
- Depth of Discharge 100%
- Efficiency 90% round-trip
- Power 7kW peak / 5kW continuous
- Supported Applications
- Solar self-consumption
- Time of use load shifting
- Off grid
- Manufacturer's Warranty 10 years
- Scalable Up to 10 Powerwall's
- Operating Temperature -20°C to 50°C (-4° to 122°F)
- Dimensions L x W x D: 1150mm x 740mm x 145mm (44" x 29" x 5.5")
- Weight 120 kg (264.4 lb)
- Installation Floor or wall mounted Indoor or outdoor
- Certification UL and IEC certified Grid code compliant
How does it work ?
We supply TESLA batteries as a service to our clients, and because the PowerWall-2 now has a built-in Solar inverter, the installation is a lot simpler, a registered electrician is required to pass the installation.
The Powerwall 2.0 is now modular, so you can add up to ten batteries side by side until you have the required kW to match your daily power consumption.
Elon Musk said “it can store 13.5 kWh of energy and provide 5kW of continuous power, but will improve to 7kW at peak. This means that the Powerwall 2.0 has twice the energy and twice the storage as the previous 6.4 kWh Powerwall.”
The Powerwall-2 comes with a 10 year warranty, the battery has a daily cycle, meaning it's designed to charge and discharge each day. The efficiency of the battery is said to be 92%, so although it has a 13.5kWh capacity, the Powerwall's working capacity is more like 12.4kWh (13.5kWh x 92%).
The danger with nearly all new & lead acid battery technologies is consistent over discharging the batteries past 80% depth of Discharge (DOD) except Nickel Iron NiFe batteries & RedFlow Zinc-Bromide Batteries, will greatly reduce the life of the Battery!
Is the Powerwall-2 big enough to take my house off the grid ?
Yes, if your household uses less than 13.kW per 24 hours, one battery will be enough to make your households independent of the electricity grid, obviously you will need to install two or more battery units to increase your storage capacity to suit your Sunset to Sunrise energy consumption.
What is the payback time ?
This is based on calculating the cost of the saving you will make on your electricity bills. There are many factors that need to be taken into account, you can get a good estimate using this calculator if you know what you currently pay for electricity.
It's also worthwhile checking if there are any state or even local government feed-in Tariff (Rebate) available for purchasing solar panels or a battery storage system. For example, Adelaide City Council are/were providing Rebates of up to $5,000 for installing solar panels or a battery storage system.
What if I already have solar panels ?
Then the payback time would be less if you already own a solar panel system that has already paid for itself in reduced energy costs. We estimate a payback time from 1~3 years, based on self consumption of all your solar energy.
Payback times will be different for every household, but in some instances where the Solar array harvests less than the Battery capacity & consumption are not compatible, the payback time may well exceed the warranty period for the Powerwall.
What's also clear, tapping into your own solar energy as much as possible, rather than feeding it back into the grid with a measly feed-in tariff, will decrease your payback time.
Can I use the Powerwall to load-shift ?
Tesla's not only plugging the Powerwall to solar owners – it's also offering it to households without solar so they can take advantage of off-peak electricity prices. The idea is to charge the battery during off-peak times, and then use the stored electricity during peak times. This is known as load-shifting – but it doesn't make much financial sense unless the off-peak rate is very cheap.
If you intent to use any battery this way, Shop around and you will find energy retailers offering Off-peak power from $0.07~$0.10kWh, some 200~400% cheaper than the daytime electricity rate!