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Tesla PW2

Posted: Mon, 13 Nov 2017, 11:40
by Rusdy
Damn this guy called Elon Musk. He hit my weak spot. I have this unhealthy addiction to anything battery powered and inverters. When one combined them both, then who am I to resist? Need to remortgage the house for this, hence, my family will live on boiled water and salt from now on (powered by PW2)!

Wheel added so it can fit to a 'vehicle' forum:
Image

My observation to date, can be found here.

Too bad Tesla took the wording out of the older advertisement: "Powerwall provides backup power during utility outages, natural disasters and even the Zombie Apocalypse (you know it's coming).". Since it's pretty much what it is at the current cost.

Re: Tesla PW2

Posted: Mon, 13 Nov 2017, 14:09
by mikedufty
Is the anti islanding, backup function when the grid goes down built in, or something that had to be installed specifically? Couldn't find much detail of that in their webpage previously.

Roughly how much did it cost installed?

Re: Tesla PW2

Posted: Mon, 13 Nov 2017, 14:22
by Rusdy
The battery and the 5kW inverter is definitely built-in to the same enclosure (with the big a$$ Tesla logo on it). The 'Gateway' box, from what the installer told me (and also from Tesla's block diagram) contains a 'switch'. I'm guessing this is a remote controlled switch (controlled by the PW2) as an anti-islanding switch. During installation, I did see a big ass circuit breaker on the 'gateway' box. The gateway box is ugly as.

So that we're on the same page, the gateway box is a separate enclosure and must be installed close to the electricity meter / DB:
Image

It cost me AUD12,100. However, my PW2 is quite a distance from the gateway box (roughly 15 metres). Also, I got charged extra since my house is 3-phase (4 CTs to monitor 3 phases and solar input).

Re: Tesla PW2

Posted: Wed, 06 Jun 2018, 12:56
by Rusdy
For those who have PW2, and found the new TBC (Time Base Control) is confusing, I did a wee bit different experiments and concluded that TBC Cost Saving with peak time extension to cover the shoulder is not a bad idea (in order to reduce solar exports, for those with poor FiT).

I also found a quirk that stop the PW2 charging from the grid during off-peak. More details here.

Re: Tesla PW2

Posted: Sat, 09 Jun 2018, 20:06
by reecho
Interesting info from a Tesla owner on his new PW2 install..

https://youtu.be/c9jpLItCJws

Re: Tesla PW2

Posted: Sat, 09 Jun 2018, 21:06
by Adverse Effects
reecho wrote:
Sat, 09 Jun 2018, 20:06
Interesting info from a Tesla owner on his new PW2 install..

https://youtu.be/c9jpLItCJws
you beat me to it been watching him for a year or 2 lol

he lives a not to far from me

Re: Tesla PW2

Posted: Thu, 05 Jul 2018, 09:19
by Chad
Adverse Effects wrote:
Sat, 09 Jun 2018, 21:06
reecho wrote:
Sat, 09 Jun 2018, 20:06
Interesting info from a Tesla owner on his new PW2 install..

https://youtu.be/c9jpLItCJws
you beat me to it been watching him for a year or 2 lol

he lives a not to far from me
Interesting.. Obviously a very savvy guy.
One question springs to mind though.. (2 actually !) ..
1)..With all the impressive data capture and display (how many monitors :shock: ).. Why did he need to hack together a separate LCD etc to show the PW capacity level ?
2)..And , what was the readout on that LCD showing ? ...84.??? What ? Cetainly not kWh (or does he have 7+ PW units ?)
But anyway,.. i thought there was a phone App that gave realtime PW data remotely ?

Re: Tesla PW2

Posted: Thu, 29 Aug 2019, 12:23
by adam lippiatt
Hi

Does anyone have current pricing in Perth for the Powerwall 2? Any installer that can be recommended?

I have a quote from over east company but I am starting to worry about the install as they told me that western power is no longer allowing the install of powerwall 2s on single phase properties with any solar already installed.

I got in touch with Western Power and they confirmed it is a 5kVA grid tied inverter limit that is in place. Affects people who already have solar adding a battery and using a hybrid inverter plus their existing grid tied inverter. Not powerwalls.

That they couldn’t tell the difference worries me.

Thanks

Adam

Re: Tesla PW2

Posted: Thu, 29 Aug 2019, 15:02
by T1 Terry
Doesn't the Powerwall have a hybrid inverter built in to it? Do you already have grid tie solar?

T1 Terry

Re: Tesla PW2

Posted: Thu, 29 Aug 2019, 15:04
by jonescg
It's an AC coupled system, so it comes with an inverter built in. Easiest option for retrofits to grid-tied solar.

Re: Tesla PW2

Posted: Thu, 29 Aug 2019, 15:18
by T1 Terry
So the original grid tie inverter would have to be removed to be able to fit the Powerwall? Here in South Australia, as soon as you touch anything to do with a grid tie system, the whole thing has to be renegotiated and generally results in a much smaller feed in tariff.
The 6kW solar and 15.5kWh battery pack we installed in Crystal Brook had to be totally separate from any connection to the grid what so ever or they would reduce his feed in tariff for the existing grid tie solar.
Now the only parts of his house on the grid is 4 power points in the kitchen and the 3 phase ducted air conditioning. Now he only knows the grid went down if visitors tell him or dinner seems to be taking a long time to cook :lol:

T1 Terry

Re: Tesla PW2

Posted: Thu, 29 Aug 2019, 18:44
by reecho
T1 Terry wrote:
Thu, 29 Aug 2019, 15:18
So the original grid tie inverter would have to be removed to be able to fit the Powerwall? Here in South Australia, as soon as you touch anything to do with a grid tie system, the whole thing has to be renegotiated and generally results in a much smaller feed in tariff.
The 6kW solar and 15.5kWh battery pack we installed in Crystal Brook had to be totally separate from any connection to the grid what so ever or they would reduce his feed in tariff for the existing grid tie solar.
Now the only parts of his house on the grid is 4 power points in the kitchen and the 3 phase ducted air conditioning. Now he only knows the grid went down if visitors tell him or dinner seems to be taking a long time to cook :lol:

T1 Terry
No...Original grid tie can stay as is.

Re: Tesla PW2

Posted: Thu, 29 Aug 2019, 21:02
by antiscab
reecho wrote: No...Original grid tie can stay as is.
Especially if you install it without telling Western Power :lol:

best of luck with the bureaucracy

Re: Tesla PW2

Posted: Fri, 30 Aug 2019, 06:31
by francisco.shi
Or you could install enough backup and panels to run off grid and tell western power that you are moving and do not want the connection anymore.
It seems it is becoming easier to go off grid. It is just a matter of how much you get for your excess electricity vs how much you pay in connection fees.

Re: Tesla PW2

Posted: Fri, 30 Aug 2019, 07:28
by bladecar
Just on the idea of going off grid completely.

I have taken notice of those times where you have heavy cloud cover for days on end, or sun showing on and off all day.
Being off grid would be great until you get that scenario. You'd have to accept that possibility and just wing it for as long as it takes for good old sunshine to kick in again. You couldn't live in a household where not everyone understood the significance of being off the grid.

Living in parts of Australia which really do have lots of sunshine and unfortunately a minimum of rain would be a bonus, to this extent.

As the weather becomes more and more unpredictable and we get cloudy days instead of fine or rain, it is a factor.

Re: Tesla PW2

Posted: Fri, 30 Aug 2019, 08:10
by Dan007a
Have played with the idea of using excess sunny days to run a water pump to fill a number of water tanks.and then release water to run water wheels for base loads on cloudy days. 200 wet days year.

Re: Tesla PW2

Posted: Fri, 30 Aug 2019, 10:30
by jonescg
For times like this, a small petrol generator would suffice. It's prudent to have a plan C anyway.

Re: Tesla PW2

Posted: Fri, 30 Aug 2019, 10:38
by jonescg
Dan007a wrote:
Fri, 30 Aug 2019, 08:10
Have played with the idea of using excess sunny days to run a water pump to fill a number of water tanks.and then release water to run water wheels for base loads on cloudy days. 200 wet days year.
For about 11 years, my folks lived in the bush east of Warwick where we had a solid 400 m of elevation behind the house. The top of the ridge wasn't our land, so it was moot, but as an exercise I worked out how much water, head, pipe and power was needed for a small scale pumped hydro scheme. I think I concluded I'd need about 100,000 litres on top of the hill, and a minimum of 25 kW of daytime solar pumping power to supply 12 hours of 3 kW of base load power. I don't think UPVC was able to restrain that much pressure, but would have been a fun (albeit expensive) exercise.

Assuming 1 litre per second flow and 400 m of head, that's 3.5 kW of power on tap. So for 24 hours you would need to release 86400 litres.

Re: Tesla PW2

Posted: Fri, 30 Aug 2019, 12:03
by Dan007a
Throw in 4 ram pumps as well for fun

Re: Tesla PW2

Posted: Fri, 30 Aug 2019, 12:32
by T1 Terry
The bother in law does have a mix of solar and hydro to charge his house battery. It is a very old Telecom lead acid battery so it doesn't hold capacity well, so must be recharged daily. He lives on the side of the Huon Valley in Tasmania, about as far south as most would live full time and Tassie is known for its generous rain fall and cloud cover.
His hydro uses a Pelton Wheel, just needs a good flow rather than high pressure, he has 2 permanent springs that feed his supply dam but there is no reason why a constant supply from something like this https://www.ebay.com.au/itm/DC-24V-284W ... 2749.l2649 couldn't be powered from a combo of solar and wind. There is the potential to add as many supply jets as required to get the required torque and jet size to get the required speed while balancing that against water use.
Not quite the idea solution for an urban house off grid system, but great for a country property with a suitable hill near the house.

Re: Tesla PW2

Posted: Sat, 31 Aug 2019, 12:13
by francisco.shi
Plan C would be to have two electric cars with 40kwh+ battery each and when supply is too low run off the car battery. When car is getting low you can go to a fast charger and recharge.
If you use say 12kwh/day your car batteries would keep you going for about a week.

Re: Tesla PW2

Posted: Sat, 31 Aug 2019, 14:03
by adam lippiatt
reecho wrote:
Thu, 29 Aug 2019, 18:44
T1 Terry wrote:
Thu, 29 Aug 2019, 15:18
So the original grid tie inverter would have to be removed to be able to fit the Powerwall? Here in South Australia, as soon as you touch anything to do with a grid tie system, the whole thing has to be renegotiated and generally results in a much smaller feed in tariff.
The 6kW solar and 15.5kWh battery pack we installed in Crystal Brook had to be totally separate from any connection to the grid what so ever or they would reduce his feed in tariff for the existing grid tie solar.
Now the only parts of his house on the grid is 4 power points in the kitchen and the 3 phase ducted air conditioning. Now he only knows the grid went down if visitors tell him or dinner seems to be taking a long time to cook :lol:

T1 Terry

No...Original grid tie can stay as is.
Yes, the original grid tied inverter stays as is.

The issue is when you install a hybrid inverter with an existing grid tied inverter. Western Power will count both for their 5kVA limit, even if you just propose using the battery inverter component.

In any event, installing a Powerwall which only has a battery inverter does not add towards the five kVA limit.

The downside is the power wall is the more expensive option (at least initially).

Re: Tesla PW2

Posted: Sat, 31 Aug 2019, 14:58
by T1 Terry
francisco.shi wrote:
Sat, 31 Aug 2019, 12:13
Plan C would be to have two electric cars with 40kwh+ battery each and when supply is too low run off the car battery. When car is getting low you can go to a fast charger and recharge.
If you use say 12kwh/day your car batteries would keep you going for about a week.
Then you need the inverter that can handle the electric vehicle battery voltage.
That raises an interesting thought. The inverter I'm looking at to use on a proposed off grid system has a solar feed in voltage max of 450vdc and between 120vdc and 430vdc the MPPT controller part can handle. If the electric vehicle battery was between these 2 figures, 120vdc and 430vdc, could the EV battery be connected to the solar input of the inverter to act as a supply?

T1 Terry

Re: Tesla PW2

Posted: Sat, 31 Aug 2019, 18:15
by antiscab
T1 Terry wrote:
Sat, 31 Aug 2019, 14:58

Then you need the inverter that can handle the electric vehicle battery voltage.
That raises an interesting thought. The inverter I'm looking at to use on a proposed off grid system has a solar feed in voltage max of 450vdc and between 120vdc and 430vdc the MPPT controller part can handle. If the electric vehicle battery was between these 2 figures, 120vdc and 430vdc, could the EV battery be connected to the solar input of the inverter to act as a supply?
Yes that works (I do that for capacity testing large packs)
The inverter will run at full power though until you either disconnect it, or the voltage goes outside it's operating window

Re: Tesla PW2

Posted: Sat, 31 Aug 2019, 18:40
by francisco.shi
I have been thinking about how to do this. As you said most solar panel strings would be able to feed the car battery directly. And most solar inverters I assume would have a 400 or so volt bus. So it may be as simple as just connecting the car battery to the internal bus and reprogramming the inverter.
This could potentially fix the duck curve produced by solar without having to spend money in storage. As we get more electric cars they can be used as domestic energy storage.