Tesla Wants to Build a Battery for Your House

[Willy T]

It doesn't fit everyone, no one solution will.

1) Do you want a backup for GT solar other than a Generator ( y/n ) ?

2) Do you have TOU pricing of at least $.30 per kwh. ( y/n )

3) What is your reimbursement rate for excess kwh ?

4) Do you want seamless backup fiddle free ( y/n )?

All of the above have to be answered before it would be of any interest to most people. Some people could break even or make money ( very few ) Any back up is usually a loser, for most it would be a waste. Then this backup would only work short term and to be of any value you'd still have to have a generator to supplement it.

Personally, I wouldn't waste a penny on it.

[kwilcox]

I still dont get the use, or market for this thing.

Most homes have peak useage, in the evenings, when the family is home. ( Lights on, TV on, oven on, etc..etc..)

So this thing charges during the day.

Wait... Peak POCO rates are during the day.... and cheapest at night.

So when exactly am I supposed to charge this thing, and use it.... to use it effectively??

I also need the device, a AC to DC rectifier to charge it, and a DC to AC inverter to use it, so I'm really buying 3 devices, plus losing efficiency at every conversion step.

I'm sticking with Solar....

My understanding is that the batteries are targeted at two usage scenarios:

• they can charge using off-peak rates (hours surrounding midnight) and discharge during peak rates (waking hours) allowing customers to take better advantage of tiered rates.
• they can be used in conjunction with a solar array. Since peak home usage is generally during the time you cite and also in the morning (shown on Tesla's site and I can validate empirically based on my own TED5000 history), the battery can leverage a solar array to store energy during peak output times (usually around noon when sun energy is highest and overall energy use is negative) and release it during morning/evening hours.

[Living Large]

It doesn't fit everyone, no one solution will.

1) Do you want a backup for GT solar other than a Generator ( y/n ) ?

2) Do you have TOU pricing of at least $.30 per kwh. ( y/n )

3) What is your reimbursement rate for excess kwh ?

4) Do you want seamless backup fiddle free ( y/n )?

All of the above have to be answered before it would be of any interest to most people. Some people could break even or make money ( very few ) Any back up is usually a loser, for most it would be a waste. Then this backup would only work short term and to be of any value you'd still have to have a generator to supplement it.

Personally, I wouldn't waste a penny on it.

I guess I haven't been clear. I am OFF GRID. A backup for me is a requirement, not a waste.

[Willy T]

I guess I haven't been clear. I am OFF GRID. A backup for me is a requirement, not a waste.

This forum is not all about you, I didn't quote you. Once you get off grid you'll get a understanding of it all.

[Sunking]

Then you know the difference in buying a emergency back up and something your going to use daily to time and power shift.

Beg your pardon but the 7 and 10 Kwh batteries are the exact same battery. The 50 cycles per year come straight from Tesla on the 10 Kwh battery which makes no sense at all. It is by no means inexpensive as Tesla has admitted no one can actually buy either battery for $3000 or $3500 dollars. More like $7000 if you buy it outright.

[Sunking]

Where did you get to the conclusion that 1hp=12,000 btu=1ton ?

1hp =745.6 watts
1 watt = 3.41 btu

745.6 x 3.41 = 2542.49 btu

1hp = 2542.49 btu.....not 12,000 btu or 1 ton.

You just walked into a movie at the conclusion and have no idea what happened. He was referring to Air Conditioning and Refrigeration in the early days when it did take 1 hp motor to turn a 1-ton compressor.

[Sunking]

My understanding is that the batteries are targeted at two usage scenarios:

• they can charge using off-peak rates (hours surrounding midnight) and discharge during peak rates (waking hours) allowing customers to take better advantage of tiered rates.
• they can be used in conjunction with a solar array. Since peak home usage is generally during the time you cite and also in the morning (shown on Tesla's site and I can validate empirically based on my own TED5000 history), the battery can leverage a solar array to store energy during peak output times (usually around noon when sun energy is highest and overall energy use is negative) and release it during morning/evening hours.

Tell us what market that works in and why. It is easy as there is only one or two markets that fits. Couple of hints:

Left Coast
Neighbors will buy your battery
Fruits and Nutz

[Willy T]

Beg your pardon but the 7 and 10 Kwh batteries are the exact same battery. The 50 cycles per year come straight from Tesla on the 10 Kwh battery which makes no sense at all. It is by no means inexpensive as Tesla has admitted no one can actually buy either battery for $3000 or $3500 dollars. More like $7000 if you buy it outright.

I beg your pardon, this comes straight from the Tesla web site, your guessing again, you have no clue of what one cooling system one may have over the other or what cells are used. I never said anything about cost, I could care less about what it costs.

Powerwall comes in 10 kWh weekly cycle and 7 kWh daily cycle models.

http://www.teslamotors.com/powerwall

[Sunking]

I beg your pardon, this comes straight from the Tesla web site, your guessing again.


http://www.teslamotors.com/powerwall

I am typing slowly so you can understand and did not listen the first 50 times when it was announced.

Only difference between them is the firmware to restrict the DOD. Both are a 400 volt 25 AH battery (10 Kwh). Same cabinet, exact same dimensions, exact same weight, exact same battery, just different firmware in the code that restricts DOD.

[Willy T]

I am typing slowly so you can understand and did not listen the first 50 times when it was announced.

Only difference between them is the firmware to restrict the DOD. Both are a 400 volt 25 AH battery (10 Kwh). Same cabinet, exact same dimensions, exact same weight, exact same battery, just different firmware in the code that restricts DOD.

Post a link from Tesla please that states exactly what your saying.

[Sunking]

Post a link from Tesla please that states exactly what your saying.

Did you try the your own link? That will give you the weights, dimensions, power out, voltage. and current all identical. Only difference is the DOD limitation.

[Willy T]

Did you try the your own link? That will give you the weights and dimensions.

Thats what I thought, only a guess.

[Sunking]

Thats what I thought, only a guess.

No that is where you start.

[Alisobob]

My understanding is that the batteries are targeted at two usage scenarios:

• they can charge using off-peak rates (hours surrounding midnight) and discharge during peak rates (waking hours) allowing customers to take better advantage of tiered rates.
• they can be used in conjunction with a solar array. Since peak home usage is generally during the time you cite and also in the morning (shown on Tesla's site and I can validate empirically based on my own TED5000 history), the battery can leverage a solar array to store energy during peak output times (usually around noon when sun energy is highest and overall energy use is negative) and release it during morning/evening hours.

1. Mornings are also "Off Peak". "Peak" is in the afternoons, when most homes are empty ( gone to work , gone to school) No need for power then

2. Solar alone has a 5 to 10 year payback window. Adding the costs of one of these might push it out to 15, 20 years? Why bother?

[kwilcox]

Here's WE Energies' time-of-use plan:

http://www.we-energies.com/residential/acctoptions/time-of-use.htm

peak rates are mornings - evenings (WE energies lets you designate this to 12 hour periods beginning at 7, 8, or 9AM). The battery use case leverages the 12 hour off-peak rates and delivers energy during peak rate times.

So here's some rough numbers...

Given that the 7KWh battery can shift 7KWh/day, and given the WE Energies rate difference of about .10/kwh we get .70/day saved or about $255/year.

Given 3,000 cost, payback is about 12 years with this use case. Not sure if its $3,000 installed or not... This also assumes that your home uses at least 7KWh/day during peak hours of course.