why tesla's powerwall is just another toy for rich green people - powerwall battery

All the breath-taking reports of Elon Musk's Powerwall battery last night missed the most important thing: for the real --world costs.
So let's look at the price of this world. shaking, game-
It really makes sense to change innovation.
Musk said Tesla's 7 KW-hour battery will cost $3,000, while the 10 KW-hour battery will cost $3,500. (
Does not include the cost of DC-AC inverter--
About $4,000 $2,000-
Professional installation. )
This means that the system at 10 KW hours can provide 10 hours of kilowatt current to your home.
It's a lot of energy.
Average household electricity consumption in the United States is 1,200 wattsthe-
According to the United States, the clockS.
Department of Energy.
The power consumption of the desktop computer is about 100 watts, and the power consumption of the large TV is about 200 watts.
The refrigerator can cycle up and down, but the average power is 100 watts.
So, what is the cost of the battery?
First, set aside the cost of making electricity first, and let's take a look at the cost of using the battery to store power and take it out again.
Former CTO of Applied Materials, researcher wenfried Hoffman, did some interesting work on the reduction in battery power costs.
He thinks lithium
The initial installation cost is $400 per kWh, the efficiency is 80%, the ability to run 5,000 cycles, and the average cost of storing power is 15 cents per kWh.
This is probably conservative.
Solar installation company Sungevity is working with a German battery company called Sonnenbattery, which claims it can do 10,000 cycles.
But this calculation may not be conservative enough.
It's not clear how many loops you can expect from Powerwall.
Tesla says its 7 KW-hour power wall can cycle every day, while the 10 KW-hour system can cycle every week.
The cost of the battery is amortized in the total amount of electricity that is circulating during its service life.
The less use, the higher the average unit cost.
Anyway, 15 cents per kilowatt hour for battery storage seems like a ball-The park is reasonable.
In order to get a real electricity bill, no matter how much you pay first, you have to add 15 cents to the battery.
Since the battery will work with solar, we will look at what Tesla's sister company SolarCity is charging customers.
According to SolarCity, customers do not pay the upfront cost of the system, but then 15 cents per kWh of electricity will be affected.
SolarCity has the ability to raise interest rates 2 in the contract.
£ 9% per year, which doesn't seem to be much, but will eventually raise your cost per kWh to more than 20 cents at the end of the 20-year term.
So by adding up 15 cents per kilowatt hour of solar energy plus 15 cents per kilowatt hour of battery in and out, you can see 30 cents per kilowatt hour of electricity.
I think 30 cents per kilowatt hour is crazy.
At my home in Texas, I pay 10 cents per kilowatt hour for electricity generated primarily by gas burning power plants.
The national average retail price is 12.
According to the department, 5 cents per kilowatt hourof Energy.
Now I know that electricity prices in California, Hawaii and the rest of the world are much higher and the grid is of poor quality, but in most parts of the United States, no one pays nearly 30 cents per kilowatt hour for electricity.
But it's getting worse.
Let's think about the real utility of this Powerwall system.
According to the Department
The average household uses 10,900 KW hours a year, equivalent to about 900 KW hours a month, or an average roundthe-
Clock power demand of 1,200 watts.
Now, with the focus on efficiency, the average household's power demand may drop to an average of 1,000 watts, which may be low enough that Tesla's 10 KW-hour power wall battery can handle about half a day's load.
The idea, of course, is that a solar panel of a 100% solar home will power the house in the day while charging the Powerwall battery, which will keep the power supply at night.
To do this, you need a solar system that is much larger than the normal solar system.
Solarcity says its average is 6.
7 KW system generates 1,400 KW power a year 【
Note: The number given on the SolarCity website seems to be wrong and should probably be an average of 6.
The 7 kw system generates 1,400 kW hours per kw per year, with an average of 9,000 kW hours per year. ].
Considering that the average family uses 10,800 KW per year, your family needs an average of 8
If it can generate enough power to get you completely out of the grid while providing enough excess power during the day to charge your power wall, then it will get bigger in size.
This is where Powerwall's economy is crashing.
If you don't have a solar system large enough to get your home completely out of the grid, it doesn't make sense to pay 30 cents per kilowatt hour to get power through Powerwall.
In the evening, when you don't generate electricity, you can simply get power from the grid.
Average 12. 5 cents a kwh.
I say in another way: Unless your sun
The energized home is completely disconnected from the grid, or your solar system is large enough to meet all your power needs, and expensive battery backup systems like Powerwall don't make any financial sense.
There is no doubt that battery technology is very important for future power grid management, but at this time, ordinary homeowners should let large power generation companies take risks and bear the cost of perfecting technology.
After all, any truly viable energy source is more economical than small-scale deployments when deployed on a large scale.
Last night Musk launched the utility with Powerwall
Power Pack available at 100 KW hours.
There is no price for that.
Whether Tesla can sell these will be the real test.