Gigafactory

Quote: kenarman

Paco you description say 37 MWh not 37 KWh which would be much more reasonable.

Good catch.

Vancouver, BC has a variety of transportation options: rental bicyles on a take one and leave it anywhere basis for a minimal flat fee (the bikes have advertising and are unique in construction and coloring), electric assist bikes, taxis, good bus and light rail systems. Even those crossing from Port Angeles, WA are actively encouraged to leave their cars in the USA. There are Pedestrian zones and residential streets are kept residential rather than being allowed to bear excess traffic.

I think the mix of options helps and the fact that many distinct neighborhoods offer so much that travel is an option rather than a necessity.

By offering bikes with lots of advertising space, the public access bikes are cheap. There are islands where the bikes can be left and no one needs to worry about theft because the unique construction means it can't be stolen even if repainted. Even the police use electric assisted bicycles. Good exercise and extra power when its needed.

Quote: Pacomartin

Tesla has released the PowerWall II.

The PowerWall I was 7kWh and cost $3000 or $3500 and had no inverter. The PowerWall II has 14 kWh and cost $5500, but it includes the inverter. So on the face of it it looks like a much better deal.

But the warranty seems to be much worse. While it is guaranteed to last 10 years, it is only under warranty for 37 MWh of aggregate throughput.
https://www.tesla.com/sites/default/files/pdfs/powerwall/Powerwall%202_AC_Warranty_USA_1-3.pdf

Somebody please correct me if I am wrong, but that sounds like a terrible deal!

For 37,000kWh at $5500 that means it costs $0.149 per kWh to run power through this battery. Even if you get your energy for free (a ridiculous assumption) and you don't consider the installation cost (~$1500) the price of $0.149 per kWh s higher than most people pay an electric company in the USA (except for a few expensive places like Hawaii).

So if you can't even fill it up and empty it for less than you pay an electric utility, how would it save you money in any realistic scenario?

My employer lets people charge electric cars all day for free. That changes the cost a bit.

Quote: kenarman

Paco you description say 37 MWh not 37 KWh which would be much more reasonable.

Quote: Pacomartin

But the warranty seems to be much worse. While it is guaranteed to last 10 years, it is only under warranty for 37 MWh of aggregate throughput.
https://www.tesla.com/sites/default/files/pdfs/powerwall/Powerwall%202_AC_Warranty_USA_1-3.pdf

Look at the link. The 37 megawatt hours is the aggregate throughput where the warranty is covered.
The battery fully charged is 14 kWh (13.5 kWh under warranty). The maximum continuous output is 5 kWh and surge is 7 kWh.

This ($727.37) Gasoline Powered Generator with Wheel Kit from Home Depot with
390cc 13 HP OHV engine provides 7,000 surge Watts and 5,500 running Watts
6.5 Gal. fuel tank with full load fuel consumption (1.18 gallons/hour)
would supply a similar amount of power as the Tesla battery but with noise and exhaust.
HOME DEPOT LINK

My point is that while the Tesla battery has a warranty for up to 10 years, if you actually use it you will throughput 37 mWh (37,000 kWh) in a very short amount of time. Some "time of use" electric plans give you free electricity at night, which you could store up in the Tesla battery, and it is available for use in the day.

Using the price of $5500 (which does not include installation) it would be more expensive to fill and discharge 37 mWh than most people people pay for electricity from utility.

In addition, while there are plans that give you "free" electricity at night, they exact other penalties that make those plans very expensive. It would only end up being free if you only used the 14kWh in the battery during the day. The minimum used at our home last year was 24.70 kWh in one day, the maximum was 139.60 kWh and average was 67.53 kWh.

Quote: Tesla PowerWall Sells Out Through 2016, Brings In $800 Million |May 12th, 2015 by Steve Hanley

Why would they not all be completed? Frankly, because many people have no idea what they are signing up for. Some analysts call it “The Prius Effect.” Once we think someone else is getting some cool, new technological bauble, we want one too.
...
Even Elon Musk admits storing residential power with the Powerwall is more expensive than grid power, but he says, “that doesn’t mean people won’t buy it.” Adds Brian Warshay, an energy and technology analyst with Bloomberg New Energy Finance, “It’s a luxury good—really cool to have—but I don’t see an economic argument” for it.

Not sure what relevance this has but 37MWh is about 4 years of electricity for my condo. It does seem that the 10 years of warranty would only come into play for limited use. Do the electric car batteries (or Tesla specifically) have such limits buried in the fine print of the longer warranties?

Quote: kenarman

Do the electric car batteries (or Tesla specifically) have such limits buried in the fine print of the longer warranties?

It isn't really fine print
https://www.tesla.com/sites/default/files/pdfs/powerwall/Powerwall%202_AC_Warranty_USA_1-3.pdf

Quote: kenarman

Not sure what relevance this has but 37MWh is about 4 years of electricity for my condo. It does seem that the 10 years of warranty would only come into play for limited use.

So you use 37000 kWh over a 4 year period or ~9,250kWh per annum, or ~25kWh per day or ~771kWh per month. Assume you only purchase one Tesla Powerwall. That only can use a maximum of 14kWh per day, so you could never run your entire home on average with one charge.

So 37,000 kWh / 14 kWh = 2,643 days = 7.24 years. But it would probably take a little longer because the warranty only says that energy retention will be 70% at 10 years.

So your condo probably is not going to have solar power. But you may purchase a power plan that gives you Free Electricity on Nights and Weekends. The idea is that you would store up energy at night in your battery when it is free, and use it during the day. But usually the "free energy" refers to generation costs and not distribution costs. In Pennsylvania generation costs are less than 8 cents per kWh.

But the price of the Powerwall is $5500. So dividing $5500 by 37,000 kWh yields 14.86 cents per kWh. Which is far over the price of energy that you save.

I think my point is that the Powerwall has to last much longer than the warranty to pay back the purchase price.

=====================
In contrast, consider a 9.5 Watt Led bulb which costs $2.22 at Home Depot. It can be used to replace a 60 Watt incandescent. It's payback time is about 400 hours. The warranty is much longer than 400 hours, and hopefully it will last as long as 15,000 hours. So if you don't break the bulb, it will probably pay itself back.

Generally if you purchase a better refrigerator, better air conditioning, better lightbulbs, a better washer, etc. you would hope that the payback period would be less than the warranty. But not so with a Powerwall.

Elon Musk openly acknowledges that the Powerwall is more expensive than grid power, but says, “that doesn’t mean people won’t buy it.”
http://www.teslarati.com/bloomberg-says-tesla-powerwall-doesnt-make-sense/


It just sort of shows you the smoke and mirrors involved. Do a websearch and tell me how often you see this kind of promotion for a product that loses money for the consumer.

1) Elon Musk said Powerwall battery demand is 'off the hook'
2) Elon Musk: Tesla's home battery business goes viral | Fortune.com
3) Tesla Energy: Has Elon Musk invented the first clean power utility?
4) Elon Musk's Grand Plan to Power the World With Batteries | WIRED
5) Tesla takes 38,000 Powerwall home battery reservations in 1 week ...

Perhaps buyers are willing to pay a 'clean energy' premium or pay a 'free from the utility' premium.

We currenetly don't have time of day electricity pricing in BC and I wouldn't expect we would ever have free power at night. Over 80% of our power is hydro generated so usually they just match demand with generation and use lower demand times to allow the reservoirs to fill. One way of looking at hydro generation is that the reservoirs are giant batteries and allow great flexibility in managing system demand.

Quote: Fleastiff

Perhaps buyers are willing to pay a 'clean energy' premium or pay a 'free from the utility' premium.

If you are getting your power with a special "time of use" plan when demand is low at nights or weekends, it is just as dirty as any other energy.

If you are getting your power from solar during the day, and then using it at night you must be willing to invest a lot of money, nearly impossible to recoup in one lifetime.

Some people are buying the batteries with eyes wide open. They know that the industry needs customers at the beginning so that someday it will be profitable. The people who paid $30 for LED lightbulbs 7 years ago must have understood that it would take years to payback the investment (unless they were burning the light 24/7 as a security light). But the industry had to sell some lightbulbs at $30 apiece so they could eventually drop the price to less than $3.

I have no objection to ideological decisions. But Musk is selling nearly a billion dollars of these stationary batteries. They are being sold with a lot of "save the planet" panache. I just don't know how many customers understand that not only will they not save money, but they are very unlikely to make back the purchase and installation price.

Exceptions include the Manhattan apartment where a generator is not an option. The owner might have thousands of dollars of food in the refrigerator that will go bad in a blackout. I had a friend who lived in Manhattan during the 1977 blackout, and she said that without air conditioning or windows that open and the ability to flush the toilet she went down the stairs and braved the riots just to get outside of her former penthouse that now resembled the black hole of Calcutta.

The clean energy premium is more along the lines of avoided cost: If I buy a battery, I am saving the utility from building more smokestacks and being more "green" which is a goal alot of fools seem to fall for just as wives fell for 'ring around the collar', fallout and other Madison Avenue jive.

People who live in Manhattan want the standby option and merely send the bills to their accountant without even opening them.