My New Favorite Battery.

[russ]

Yeah! He disagrees with us -- must be an ENEMY! Get out the tar and feathers!

Anyone that disagrees with you Dan must have at least a little bit on the ball.

[Sunny Solar]

Anyone writing "deja vu all over again" doesn't even understand what the phrase means.[/QUOTE]

Probably gets his money from an ATM machine also..

[russ]

So - do you feel good about yourself for spending that kind of money?

Seriously though, the people I know that have an EV it's actually cost effective because they drive enough each day, and the cost of gas vs. cost of electricity more than makes up for the difference in vehicle price.

Only because your neighbors are paying the way for them.

[J.P.M.]

Anyone writing "deja vu all over again" doesn't even understand what the phrase means.

Probably gets his money from an ATM machine also..[/QUOTE]

I don't think ATM's were around when Yogi Berra uttered that phrase.

[russ]

Probably gets his money from an ATM machine also..

I don't think ATM's were around when Yogi Berra uttered that phrase.[/QUOTE]

I liked the quote from Yogi, "It ain't over 'til the fat lady sings".

[Sunking]

What I'd like to know is how they are going to integrate this new high-voltage (350 - 450Vdc) Tesla battery into a home system. I assume its going to be grid-tied, but I don't know of any current inverter that can work with this battery. They say SolarEdge is going to have something compatible. Great - another new, unproven item. I've been waiting for 30 years for a battery "breakthrough". God knows the industry needs it. Maybe this is it, but I'll stick with Trojan for now. This new industrial version sounds pretty good to me. The big advantage of lithium batteries is the much better energy density, but in a stationary application, who cares?

Finally someone who actually is thinking things out and asking the right questions. As of now there is no solution, but that is not Tesla problem that is the customers problem to figure out. If you read the latest press there are some catches Mr Musk did not initially bring to the surface until pressed for answers. First catch is the new batteries will be distributed and installed through Solar City, and the $3000 cost does not include any of that. This is not a DIY battery. Once you go above 50 volts nominal all the electrical rules change.

Tesla is not providing any ancillary equipment to make the battery work, that is a customer problem to figure out at their own expense and time. Then they are required to use Solar City to install all of it. So hats off to you Solarix you did not go Ooh and Ahh and salivate with Green Blinders and fingers in your ears. You asked some good questions.

Can you use a 350 to 450 volt battery Inverter and do they exist? Sure do just about all commercial UPS use high voltage DC inverters. But those are Commercial and Industrial grade Battery Inverters and come with a commercial industrial price tag. They also operate in the 6 and 7 digit wattage range.

I know the next response and question from the Green Blind crowd: Grid Tied Inverters operate at that voltage. Well they most certainly do but that has nothing to do with a BATTERY INVERTER. What it will take is a Hybrid Inverter and all those on the market are made for 12, 24, and 48 volt systems all operating under that magic 50 volt limit the Green Blind Crowd keeps ignoring and does not want to hear about. It can be done, but none exist that I know of for the consumer markets. What you wanna bet that is Tesla next move?

Look guys I am all for EV's, I own a NEV, and a huge fan of Lithium batteries. But there are still a lot of challenges and hurdles left to be overcome before they become mainstream. The biggest hurdle of them all is power generation and transmission. Solar is not going to solve that problem, so it does no good to have a battery if there is no way to generate the power to be stored and used later on a commercial scale. The next hurdl;e which is being worked on is a Lithium battery that does not exist as of yet, but there are prototypes on the table. But they have to figure out how to make them affordable and still have a problem with the high energy density materials are rare with limited supply. Does not make sense to make a battery from rare earth materials with more limited quantities than current fossil fuels. Especially when you are standing on a few million years of dirt cheap fuel emission free fuel and refuse to use it.

What Tesla is banking on is California customers trying to load shift. That is putting a band aid on a severed limb trying to stop the bleeding. The real issue is base load or lack of power generation. California demand exceeds capacity, 30% of CA electricity is imported. That is up from 10% 20 years ago when CA decided to quit building power plants and go RE. A battery is not going to solve any problems the state is facing.

As for Tesla battery, well just way to many unanswered questions and using a $3000 price tag is just Bait and Switch tactic. Elon Musk is a very smart businessman who makes a very good EV, and figured out a way to make money off California energy crisis. It does not solve the problem, he just figured out a way to profit from it and the more power to him for doing that. He figured out a way to profit from your misery and a lot of you like that. Take off the Green Blinders and you may see things in a different light when you ask real informed questions.

[DanKegel]

Grid Tied Inverters operate at that voltage. Well they most certainly do but that has nothing to do with a BATTERY INVERTER. What it will take is a Hybrid Inverter and all those on the market are made for 12, 24, and 48 volt systems all operating under that magic 50 volt limit the Green Blind Crowd keeps ignoring and does not want to hear about. It can be done, but none exist that I know of for the consumer markets. What you wanna bet that is Tesla next move?

Tesla said they're partnering with SolarEdge, which has been making noises about coming out with a battery inverter ("StorEdge") since June 2013, but evidently that's a 48v system (from http://www.aurora-energy.com/solar-e...ckup-solution/ ).

Where does the "magic 50 volt limit" come from? Is that from limitations in power semiconductors?

BTW I agree that the cost for a system using Tesla batteries is probably higher than the $3500 battery-only figure quoted. http://www.bloomberg.com/news/articl...rting-at-5-000 mentions an installed system price of $7140.

[inetdog]

Tesla said they're partnering with SolarEdge, which has been making noises about coming out with a battery inverter ("StorEdge") since June 2013, but evidently that's a 48v system (from http://www.aurora-energy.com/solar-e...ckup-solution/ ).

Where does the "magic 50 volt limit" come from? Is that from limitations in power semiconductors?

BTW I agree that the cost for a system using Tesla batteries is probably higher than the $3500 battery-only figure quoted. http://www.bloomberg.com/news/articl...rting-at-5-000 mentions an installed system price of $7140.

One of the magic 50V limits comes from the National Electrical Code, which adds a lot more restrictions on what you can do once you go above 50 volts.

[foo1bar]

One of the magic 50V limits comes from the National Electrical Code, which adds a lot more restrictions on what you can do once you go above 50 volts.

What difference does it make if the batteries are 48V or 350V? Either way it's tying into house voltage at 110/220 AC. So it seems to me that it's just whether you're dealing with half the system being over 50V or all of it.

My guess is it'll probably be even easier than a typical 48V system. My guess is the battery banks and the inverter will come pre-wired so all that has to be done is plug them together and hook them up on the AC side. (where typical 48V system you have to deal with all the wiring from one battery to the next, and big cables from the batteries to inverter.) Even if they aren't setup to just be plugged together, it's probably going to just put some conduit between them, pull 6-10 AWG wire through the conduit, and hook up with simple connectors (screw or spring clamp) instead of crimping on big connectors onto big cables.

[DanKegel]

What difference does it make if the batteries are 48V or 350V?

Maybe this is part of what he's talking about: http://en.wikipedia.org/wiki/Low_voltage mentions "the United States 2005 National Electrical Code (NEC) defines low (distribution system) voltage as 0 - 49 volts. Low distribution system voltage is covered by 250.20(A) of this code."

[donald]

The Powerwall converts the DC out to 48v.
The 400v figure is internal. I suppose Tesla is proud off that number because that is apparently how their supercharger works on their cars.
The input/charger side of the powerwall is apparently AC and DC. They build a similiar charge controller into their cars.

So add $500-$700 for a 48v 2000w inverter. Or less if the output can be reduced below 48v.

All in all a good deal. Sunkings nice Trojan batteries used at 50% DOD are about the same cost per watt hour. But no charge control, no BMS, no fancy software interface that hasn't been shown yet.

After listening to Musk's presentation, I now think these will allow off grid in the warranty.

There's not going to be anything highly unusual for a residential install of this device, like wiring for 400v DC. I'll even bet that it's designed to be installed by a single person. Too many Apple employees at Tesla for this to be a half baked product.

[Sunking]

The Powerwall converts the DC out to 48v.

Not to my knowledge or anyone else. Just 350 to 450 DC output.

[Sunking]

So add $500-$700 for a 48v 2000w inverter. Or less if the output can be reduced below 48v.

All in all a good deal. Sunkings nice Trojan batteries used at 50% DOD are about the same cost per watt hour.

Not even close. The Trojan lineup can be operated to 80% DOD same as Tesla to over 2500 cycles with a real 8 year capacity warranty. No need for any BMS, Liquid cooling or inverters not on the market yet. The charger for Tesla is a plain ole 240 VAC line voltage. No way to input solar other than GTI.

Real cost for the battery is in excess of $7000 installed by exclusive installer Solar City.

[donald]

Not to my knowledge or anyone else. Just 350 to 450 DC output.

I believe I heard that in the presentation. I hate to listen to the whole thing again. I just don't see them exposing 400v dc in a residential application.

[donald]

Not even close. The Trojan lineup can be operated to 80% DOD same as Tesla to over 2500 cycles with a real 8 year capacity warranty. No need for any BMS, Liquid cooling or inverters not on the market. The charger for Tesla is a plain ole 240 VAC line voltage. No way to input solar other than GTI. You got all your facts wrong.

80% is 1500 cycles. Probably less off grid. What will the life be in real world solar where the batteries seldom get through absorb?