BajaNomad

Solar Energy Battery Storage With Tesla Powerwall

StuckSucks - 4-11-2018 at 05:20 PM

Heads up, this is from Australia, but the same can be had in North America.

Solar Energy Battery Storage With Tesla Powerwall

$12499 for a 13.5 kWh system fully installed.

Each Powerwall battery pack is a self contained module consisting of battery cells, battery management system and an integrated AC/DC inverter. Mutiple Powerwall battery packs can be daisy chained together. The battery packs are connected to the meter board via an AC circuit. The battery packs will draw power from the AC circuit and start recharging when signaled by the Energy Gateway that the building is producing surplus energy and exporting to the grid. The batteries will discharge power into the AC circuit when signaled by the Energy Gateway that the building is importing energy from the grid. The building draws from the external grid when the Powerwall reaches its reserve.

Each Powerwall battery pack has a usable capacity of 13.5 kWh and a discharge rate of 5 kW continuous and 7 kW peak. Up to 9 Powerwall battery packs can be installed in a cluster.

The Powerwall has a 10 year warranty.

ehall - 4-11-2018 at 06:40 PM

Interesting to see if the price comes down in the next couple years. Thats too big a nut for a lot of people

DavidT - 4-11-2018 at 08:35 PM



Tesla shows two 13.5 kWh Powerwalls for $12,500 with supporting hardware and typical installation cost from $800 to $2000.

Fun fact: In Florida by law grid tied solar panels without battery banks in homes must be shut down when the grid is down, like during and after the hurricanes last year. So even if they are functional and the mandatory grid disconnect switch is locked open you still can't use them.
And even if you install a full battery backed off grid capable system by law you must remain connected to the grid or you lose your certificate of occupancy.

ehall - 4-11-2018 at 09:13 PM

Quote: Originally posted by DavidT  


Tesla shows two 13.5 kWh Powerwalls for $12,500 with supporting hardware and typical installation cost from $800 to $2000.

Fun fact: In Florida by law grid tied solar panels without battery banks in homes must be shut down when the grid is down, like during and after the hurricanes last year. So even if they are functional and the mandatory grid disconnect switch is locked open you still can't use them.
And even if you install a full battery backed off grid capable system by law you must remain connected to the grid or you lose your certificate of occupancy.



Utility companies have a strong lobby.

tecatero - 4-12-2018 at 03:55 AM

be very interesting to see the " off grid" version,,,,,,,,,,Baja would be a great market to see if they hold up.......Looks like the Outback systems will have to do for a few more years

BajaTed - 4-12-2018 at 10:13 AM

Is below ground installation part of the powerwall spec. ???
Concern is physical security and optimal performance

mtgoat666 - 4-12-2018 at 10:26 AM

Quote: Originally posted by ehall  
Quote: Originally posted by DavidT  


Tesla shows two 13.5 kWh Powerwalls for $12,500 with supporting hardware and typical installation cost from $800 to $2000.

Fun fact: In Florida by law grid tied solar panels without battery banks in homes must be shut down when the grid is down, like during and after the hurricanes last year. So even if they are functional and the mandatory grid disconnect switch is locked open you still can't use them.
And even if you install a full battery backed off grid capable system by law you must remain connected to the grid or you lose your certificate of occupancy.



Utility companies have a strong lobby.


the requirement to automatically shutoff solar power feed during transmission grid outage is to protect line workers. If the line is de-energized to allow safe work on lines, you need to prevent all the solar producers from energizing that line.

perhaps if batteries become more common a new safe disconnect system will come about?

StuckSucks - 4-12-2018 at 11:06 AM

Quote: Originally posted by mtgoat666  

the requirement to automatically shutoff solar power feed during transmission grid outage is to protect line workers. If the line is de-energized to allow safe work on lines, you need to prevent all the solar producers from energizing that line.


I learned this the hard way at the office. We are totally solar there, but LA City power went down outside, so we did too (for the reason mentioned). I'm optimistic that we will eventually figure a way to keep our building alive while protecting electrical workers outside.

ehall - 4-12-2018 at 01:35 PM

Quote: Originally posted by StuckSucks  
Quote: Originally posted by mtgoat666  

the requirement to automatically shutoff solar power feed during transmission grid outage is to protect line workers. If the line is de-energized to allow safe work on lines, you need to prevent all the solar producers from energizing that line.


I learned this the hard way at the office. We are totally solar there, but LA City power went down outside, so we did too (for the reason mentioned). I'm optimistic that we will eventually figure a way to keep our building alive while protecting electrical workers outside.




Automatic transfer switches have been around for a long time. They are used on backup generators all the time.

Timinator - 4-12-2018 at 05:03 PM

So is the Inverter in these systems a 5KW Inverter with 7K peaks? What is the voltage of the system, 48V?

Bob and Susan - 4-13-2018 at 04:27 AM

I'm sure its a slick looking box for the house

the inside is a bunch of littler batteries hooked together
(like a laptop battery)
with a built in charge controller and inverter



the voltage doesn't matter with something like this
because whatever you send to it it will convert it to what it needs
and give you 120v out


mjs - 4-13-2018 at 08:31 AM

Battery voltage is approx 600 volts. One of the reasons it is only sod with professional installation.

For comparison, 13.5 kW is equal to a 24-volt, 540 amp-hour battery bank. A comparable 24-volt forklift battery (12-85-13, 810 ah) is about $2000.

Timinator - 4-13-2018 at 09:17 AM

So are the solar panels that you'd connect to this proprietary or can you use normal panels. Then....if normal panels, you could hook them up either 12, 24 or 48 and "it" would take care of the rest??

LukeJobbins - 4-13-2018 at 09:51 AM

This came out several years ago but Tesla was and probably is still having financial issues. It was originally put out by Elon musk at a hotel conference years ago where he said it would be just over 2000 dollars to buy. The original goal was to even out the electric bills by having a smart battery that would charge during lowest rate periods and then switch to full battery use for the home during peak rate times. But while his thinking is top notch his financials are not. Tesla cars cost more than predicted by him. The solar tiles are more expensive than he said they would be. The battery is more expensive. He is an amazing innovator and his thinking is beneficial to humanity but people should be skeptical of his business practices. If Tesla goes down there is no one around right now to service or replace broken products. Most of Las Vegas is powered by his renewable energy technologies and if I am not mistaken most of his conferences are powered by the batteries. A few hotels around the world use them as well.

DavidT - 4-13-2018 at 09:59 AM

Tesla Powerwall 2 AC owners manual

Powerwall 2 AC Spec sheet

Powerwall 2 DC data sheet

Looks like it is 50 VDC in either the AC or DC Powerwall


DavidT - 4-13-2018 at 10:21 AM

Quote: Originally posted by mtgoat666  


the requirement to automatically shutoff solar power feed during transmission grid outage is to protect line workers. If the line is de-energized to allow safe work on lines, you need to prevent all the solar producers from energizing that line.

perhaps if batteries become more common a new safe disconnect system will come about?



As I understand it it also has to do with the systems needing to synchronize with each other and the grid is the master with individual systems syncing to it.
With the grid down individual systems could sync with each other and cause problems when the grid comes online. All this in addition to protecting linemen from a live wire.
However I believe that you can lock out the master disconnect, going off grid, and still not be allowed to use your solar panels in your own house.
Unless you also have battery backup, then you can go off grid and use your system during power outages but you can't legally disconnect from the grid permanently.