Is The Tesla Powerwall All That Is Promised?
Here at Smart Commercial Solar, we are all about solar's financial viability as a solution that works for businesses today since price parity is a reality. The Tesla Powerwall sounds exciting. But will it do what it promises at the costs it promises? The jury is still out. Here's an interesting article on the "real" costs of the Tesla Powerwall:
All the breathless coverage of Elon Musk’s Powerwall battery brouhaha last night is missing the most important thing: a sober discussion of real-world costs. So let’s take a look at the costs and see if this world-shaking, game-changing innovation really makes any sense.
Musk said Tesla’s 7 kwh capacity battery would cost $3,000, while the 10 kwh capacity one would be $3,500. (That doesn’t include the cost of a DC-AC inverter – about $4,000 $2,000– plus professional installation.)
The implication is that a 10 kwh system could supply 1,000 watts of current to your home for 10 hours. That’s a good amount of energy. The average American home draws an average of 1,200 watts of power around-the-clock, according to the U.S. Department of Energy. For a sense of scale, a desktop computer draws about 100 watts, a big TV 200 watts. Refrigerators cycle on and off, but average about 100 watts.
So how much is that battery power going to cost? Setting aside for a moment the cost of making that electricity in the first place, let’s look at just the cost of using the battery to store it and get it out again. Researcher Winfried Hoffman, the former CTO of Applied Materials AMAT +0.58%, has done some interesting work on the falling costs of battery power. He figures that for a lithium-ion system with an initial installation cost of $400 per kwh capacity, 80% efficiency and ability to run 5,000 cycles, the average cost of stored electricity will be 15 cents per kwh.