Uber is disruptive. Powerwall isn’t. Powerwall is mostly disruptive to the owner’s bank account. It solves no problem, but it does create new ones.
In last year’s post, I assessed the cost of electricity storage via the 7 kWh Powerwall. Over the lifetime of the unit, the cost per kWh would be 11.7¢ per kWh, kWh and installation not included. In other words, the storage alone costs 11.7¢. Imagine if your gas tank alone cost you $30 every time you filled up with gasoline! The 11.7¢ is based on fully charging and depleting the battery every single day during the warranty period.
Earlier this spring, Tesla ceased production of its 10kWh backup battery pack because the economics were, uh, crumby. For several thousand dollars it would supply 2 kW for less than five hours. For $400 my gasoline-fired generator will provide 2 kW indefinitely.
As for spin Tesla says, “Due to the interest, we have decided to focus entirely on building and deploying the 7-kilowatt-hour Daily Powerwall at this time.” Translation: Due to misbegotten plans, we are killing the 10 kWh bad idea.
Public Utilities Fortnightly reports that shortly after the rollout a year ago, 38,000 Powerwall units were ordered, creating a “sellout” through mid-2016. A year later (today), “a handful (yes, I mean about five) have actually been installed” worldwide. None have been installed in the US. The handful went to Germany and Australia.
As for cost, Musk expected customers to pay $4,000 for an installed unit. This includes installation cost of roughly $1,000. Green Mountain Power, which may install some of these as pilots, has an installation cost of $6,500, and the ones installed in Australia cost $7,100.
On top of this, it turns out the 10 year warranty only covers 60% of the battery capacity at the end of the warranty period. So, it is really only good for 4 kWh – about 13 minutes of a hot shower from electrically heated water. Ooooh.
About the annoyances, Greentech Media reports, German users complain of Powerwall noise, as high as 80 decibels (dB). How loud is 80 dB? About the level at curbside of a busy street. Conversation is about 60 dB, unless you have a lousy speakerphone system; in that case it’s closer to 75 dB. Note that decibels are measurements on a log scale, like the Richter scale. Eighty dB is 100 times more powerful than 60 dB.
This noise is a problem for Powerwall customers. They should think twice about adding it to their art collection in the cocktail parlor. Powerwall doesn’t pair well with Picasso or Mozart. As the Fortnightly guy says, it is a better fit next to the electric panel in the basement next to the toilet parts.
Triggering the DNA
A few weeks ago in Burning Behavior Barricades Down, I attempted to quantify the importance of thought and behavior for various types of programs. Upstream widget programs require less thought and behavior. Cerebrally intensive knowledge-based programs, like energy information systems, commercial and industrial new construction, and retro-commissioning are on the opposite end.
Speaking of widget programs and marketing, I can’t resist sharing a recent TV ad for the Twitching Lure. These daytime info-ads are for the gullible, but they often entertain me at the end where they add accessories, smaller models, larger models, and then double it all then cut the price in half! But that’s not all! The Twitching Lure catches every species of fish that swims in water. “It triggers their DNA.” Wow – that is something (and makes me laugh out loud even now)!
In fact, intelligent efficiency does bear some resemblance to fishing lures. Growing up through my college years, our family vacation was a weekly fishing trip to Northern Minnesota/Ontario. The largest walleye (the state fish) I ever caught was just over 10 pounds using an unpainted 3/8 ounce jig and minnow – total cost: roughly 25¢. Twitching Lure cost: $20.
This is all assembled in the chart below. The effective stuff is simple, boring, lacks flash, and/or requires some skill and knowledge. The flashy stuff is conceptually simple, but don’t look at the numbers. Watch the hand!
 Who knew a battery would be sexy?
 There were (key word) two models: the 7 kWh model designed for daily cycling and the 10 kWh model designed for backup power and far less cycling.