This article was published 9 years ago

Notes on Tesla’s Powerwall and how it could be the device that changes the world

Tesla Model S powerwall
A Tesla Model S being charged off a powerwall. – Image credit: Tesla

Elon Musk is on a crusade to be the pioneer with the combination of Steve Jobs, Henry Ford and Captain Planet. He resurrected the electric car; he wants to send people to Mars with reusable rockets and an idea to get from Los Angeles to San Francisco in 30 minutes using tubes. When Musk announced his company will build a battery factory (called the Gigafactory) in Nevada, we thought it was only for cars. Last night Musk revealed the new phase of Tesla, the Powerwall.

Here are some thoughts from last night.


I’m curious how the media – those not in attendance – will view the Powerwall announcement because it was suppose to start at 8:30PM Pacific time but because of a delay, it did not start until 9:18P Pacific. Those on the east coast did not see the announcement until well after Midnight. Add in the protests in Baltimore, Philadelphia and elsewhere plus the NFL Draft in Chicago means this announcement will not be covered very well.

If you want the notice of the press, this should have been done in the morning or afternoon. Everybody does this. The only major stories today were from Microsoft with their age detection API, hololens reviews and Circa is looking for a buyer.

Powerwall would have been the dominate topic in news and might have been featured on the nightly news before the first commercial break.


Besides the poor keynote job, Tesla unveiled its’ newest product: the Powerwall. A 52 foot by 34 foot wall-mounted battery that can be charged from either the power grid or solar panels that comes in either 10 kWh for $3,500 or 7 kWh for $3,000 and can be daisy-chained (multiple batteries hooked together). The battery charges during the middle of the day and runs on batteries at night. Combined with solar panels, you could disconnect the house from the electric grid. This can be a second option if you live in an area that forbids solar panels (HOAs) or the cost is too expensive – this solution starts at $3,000 so its not a cheap alternative.

The Batteries

Musk guarantees that the batteries in Powerwall will last ten years. What we know about all lithium-ion batteries – as powerwall uses them – is that over time, the cells lose their charge and either won’t fully charge or quickly discharged when powered on.

It will be interesting to see if Tesla found a way to keep batteries from losing its charge over long periods of time. The data from their electric cars probably solved – or at least, slowed – the discharging of cells.

Disruption of power

With the Powerwall, Power companies have been added to the disruption lists just like Uber did for taxis, Craigslist did to newspapers and Netflix did to cable TV and video rentals. Now Tesla is disrupting the energy market.

Powerwall can be used in different ways, even without solar panels. If fact, you can make a power company with nothing but a solar and battery farm and run electric wires to the homes in small communities (don’t expect this to happen in large metropolitan areas. It would take 160 million Powerwalls to electrify households in the United States). But in rural villages or even small towns in China, it can happen.

You can have a powerwall unit even without solar panels. One of the major sticking points Musk reiterated during the keynote how Powerwall can be charged during the daytime when electric rates are cheap and run off the battery at night. That example is savings for everyone: saves money for the customer, saves demand for the power grid and cuts down on CO2 emissions from the power plant. Imagine getting a power bill for $8 a month (estimate), only for charging the battery.

Only thing it doesn’t save is bank account of the power company.

Getting people to solar

Probably the only thing keeping Powerwall from taking off will be the cost. The unit starts at $3,000 and it doesn’t include solar panels. $3,000 isn’t something most people have laying around.

It will be difficult getting Powerwall added as a tax deducible like solar panels are in some places of the country. Louisiana will let the solar panel tax expire as the state is facing a $1 billion deficit.

Expect the power utilities to lobby hard to keep Powerwall from being a tax credit, both in state and federal. They will see this as a threat to their bottom line and will do everything they can to slow the switch to solar.

The good part is that since many people are adding solar panels to their houses, prices should drop. And if enough people buy Powerwalls for their homes, so should the prices fall for battery units as well.

A real chance at beating global warming/climate change

Count me as one of those people that believes global warming is a real issue but in the sub-category of I’m not changing my habits and we’re doomed no matter what we do to solve the problem.

Reading Elon Musk present Powerwall as a smart battery to make houses energy efficient made me change my viewpoint from doom and gloom to maybe a fighting chance to solve.

What makes my viewpoint change is the multiple ways Powerwall can be charged. Charge during the daytime, shut off the electric grid at night and run off the Powerwall. I wonder how much CO2 emissions would be saved by that scenario.

Tesla will begin shipping the 220 pound Powerwall this Summer and will require a trained electrician to install the unit to the house.