The Tesla Powerwall 2 has a lot of hype surrounding it but is it worth the money? How long will it take a Powerwall 2 to pay for itself?
If the Powerwall 2 pays for itself in a short period of time then it could be seen as a great investment for households. If, however, it doesn’t pay for itself then it will likely just be a niche product for families wanting to go green or those needing to go off grid.
How The Powerwall 2 Pays For Itself
Households spend money buying electricity from the grid. Depending on your location this ranges from about 10-30c per kWh.
Electric choice as well as the EIA put Washington as one of if not the cheapest states to get electricity with under 10c per kWh. Hawaii is the most expensive at around 27.5c per kWh.
The Powerwall 2 saves you money by either:
- Storing electricity you generate during the day from your own solar panels
- Storing electricity from the grid in off-peak times when electricity is cheaper.
For the Powerwall 2 to pay for itself it would have to save you more in electricity costs than it costs to purchase.
Saving money by using electricity to charge your battery in the off peak is unlikely to lead to huge savings. So to calculate the payoff period we’ll look at just energy stored from your own solar panels.
How Much Is A Tesla Powerwall 2
According to Tesla’s site a single Powerwall 2 costs $5,500 + $700 in supporting hardware. This is a total cost of $6,200.
Prices vary from country to country. For example in Australia it will cost you roughly $10,395 according to Solar Quotes and the Germany it would cost 6.750 €
How Many Days To Pay Off The Tesla Powerwall 2
The Powerwall 2 has a storage capacity of 13.5kWh when purchased. This means the maximum electricity you can save per day on a fully charged powerwall is 13.5kWh.
Using the US average cost of 12.82c/kWh for electricity we can calculate that a Powerwall 2 will save you $1.73/day if fully used.
So if you fully used it every day it would take 3,582.35 days to pay off your Powerwall 2.
It will take you 9.8 years to pay off a Powerwall 2 IF you fully used it everyday.
But, and it’s a very big but, this is assuming you use it fully every night of every day of every month of every year. It’s also assuming you fully recharge from your own solar panels everyday and it assumes no feed-in tariffs and no degrading of the battery.
Basically the figure of 9.8 years I gave you is nearly impossible to achieve.
Why The Tesla Powerwall 2 Will Take 10+ Years To Pay Off
The average family uses under 20 kWh per day of electricity with maybe half of that being used at night. This means it would take a large family or someone with extremely high power consumption to fully use the 13.5 kWh the Powerwall holds every single night.
Plus people go away on holidays, spend nights at friends houses or use less electricity on some nights for one reason or another.
So let’s assume usage of 10 kWh per night with 4 weeks away each year.
Under this more realistic case the Powerwall 2 would pay itself off in 14.35 years
The Powerwall 2 is only under warranty for 10 years, so it may never actuallypay for itself at all if it breaks after the 10 year period.
What About In Hawaii?
Hawaii has the most expensive electricity prices in the US with costs around 29.39c/kWh.
Because electricity is more expensive in Hawaii you are saving more money faster.
In the perfect usage example the Powerwall 2 will pay for itself in 4.3 years. In the more realistic example it’ll pay for itself in 6.2 years.
You’re Likely Better Off Waiting For The Powerwall 3
According to GreenTechMedia the company Stem is paying 70% less for lithium-ion batteries than they were just 18 months ago and they expect a similar drop to happen in the next 18-24 months as well.
Chances are a Powerwall 3 would pay itself off before the Powerwall 2 ever does, and that’s even taking into account the fact that you’de have to wait a couple of years before the Powerwall 3 comes out.
This is a rapidly advancing technology that is likely to get a lot cheaper in the coming years. For me it makes more sense to wait for the technology to get cheaper than it does to buy a Powerwall 2 now.
A better investment would be to replace all your globes with new LED globes as this has a payoff period of less than a year.
Powerwall 2 Is Still Great For Some Situations
If you’re completely off grid then a Powerwall 2 will likely be a much easier solution than the standard lead-acid battery setups most off-grid homes have at the moment.
The Powerwall 2 is also a great option for consumers who want to use completely green energy rather than pulling from the grid at night. Instead of using electricity produced from burning coal these home owners can use energy from their own solar panels at night instead. The Powerwall 2 is a great solution for this.
So while the Powerwall 2 is unlikely to pay for itself in any respectable time frame it’s still exciting to see how this technology is developing and in the coming years it’s likely that it will make financial sense for all of us to have a Powerwall in our homes.