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How much do you charge from solar in Australia?

What percentage of your car battery is charged with work/home solar?

  • More than 75%

    Votes: 26 43.3%
  • 51% to 75%

    Votes: 6 10.0%
  • 26% to 50%

    Votes: 8 13.3%
  • Nil to 25%

    Votes: 20 33.3%

  • Total voters
    60
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srwx- that's awesome. I've been badgering Tesla for the past 18 months trying to get them to implement such a scheme...to me is the holy grail to have any excess solar charging my Tesla automatically. For now I just wait for the PW2 to be fully charged then through the Tesla app activate charging of the car with the charge limit set to 5kW
 
I reckon I charge more then 90% from my off grid 25KW system, just the odd charge from a grid connected charger when venturing far away from home.I own the car for only a month, so will have a look in my TeslaFi next year to see how much I charged elsewhere.I will soon use the battery pack from the MX to help me get through winter, as my 28KW home battery is sometimes not enough to get me to through a few overcast days in a row in the middle of winter.
 
Roughly 0% for us.

We have a 16.4 kW solar system with 2 x 16 kWh Sonnen batteries. The batteries capture most surplus solar production, especially at this time of year:

energy1.png


energy2.png


I have also written software ("Energy Genie") which forecasts tomorrow's solar production (using Solcast — data and tools to build the solar future) and energy consumption (using locally-captured time series data), then every hour models the upcoming ~550 manual charging options to determine if a manual charge from grid will reduce overall energy cost. This takes into account inverter inefficiencies etc.

At this time of year Energy Genie generally causes a manual charge for 1-2 hours during the nightly off-peak, but sometimes it surprises me with a charge late in the morning. This happens when consumption was higher than forecast in the morning, or production was lower than forecast, so it's doing a quick charge before the afternoon peak starts. Here's a chart showing what Energy Genie thinks will happen over the next 24 hours without its intervention (not a great day, the batteries will only get to about 43% state of charge):

energy-genie-self-consumption.png


I have considered adding the Tesla APIs to Energy Genie so it can kick off a manual charge if it forecasts surplus solar energy may "escape" to the grid. However it would not improve things very much given the default Sonnen self-consumption mode supplemented with Energy Genie overrides.
 
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Roughly 0% for us.

We have a 16.4 kW solar system with 2 x 16 kWh Sonnen batteries. The batteries capture most surplus solar production, especially at this time of year:

View attachment 392594

View attachment 392595

I have also written software ("Energy Genie") which forecasts tomorrow's solar production (using Solcast — data and tools to build the solar future) and energy consumption (using locally-captured time series data), then every hour models the upcoming ~550 manual charging options to determine if a manual charge from grid will reduce overall energy cost. This takes into account inverter inefficiencies etc.

At this time of year Energy Genie generally causes a manual charge for 1-2 hours during the nightly off-peak, but sometimes it surprises me with a charge late in the morning. This happens when consumption was higher than forecast in the morning, or production was lower than forecast, so it's doing a quick charge before the afternoon peak starts. Here's a chart showing what Energy Genie thinks will happen over the next 24 hours without its intervention (not a great day, the batteries will only get to about 43% state of charge):

View attachment 392597

I have considered adding the Tesla APIs to Energy Genie so it can kick off a manual charge if it forecasts surplus solar energy may "escape" to the grid. However it would not improve things very much given the default Sonnen self-consumption mode supplemented with Energy Genie overrides.
That is impressively complex
 
For me very little because I get paid more to export solar than to buy carbon zero electricity late at night.

Is there a date when you lose the high feed in tariff? In Western Australia the extra 40cents per unit incentive concludes for all remaining customers in mid 2021, those lucky enough to still be on 40+7 cents drop back to the standard 7 cents (for inverters 5kw or less). A fair proportion of those householders will already be planning their battery installation now.
 
Is there a date when you lose the high feed in tariff? In Western Australia the extra 40cents per unit incentive concludes for all remaining customers in mid 2021, those lucky enough to still be on 40+7 cents drop back to the standard 7 cents (for inverters 5kw or less). A fair proportion of those householders will already be planning their battery installation now.
I’m getting 10.2c/kWh feed in and Powershop are charging 9.02c/kWh between 0000 and 0400 when I charge my car. Other providers in NSW are paying 15.2c/kWh but I’m not sure of the consumption rates. NSW’s very high feed in tariff finished some time ago.
 
There's Origin Energy "solar optimiser" plan (NSW) that gives 21c/kWh FIT.
It's ~29c/kWh flat price though - no off-peak and no discounts, but for decently sized solar system it pays out.
I think this is the maximum FIT available right now.
Expecting negative bill coming soon :)
 
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So I put down 51-75% as I charge twice a week. Usually during the week on Wednesday evening from grid (controlled load) and during weekend only from solar. I do feed loads of solar in during the week, but cannot use it as I am at work with the car. I have 5kw solar system.
 
The other incentive is that now we've lost our pawltry 7c feed in tariff there is even more reason not to give Synergy any free juice.]
Yeh, greatest scam every they are. They have the monopoly in WA, they consistently lose money every year so as tax payers we prop them up, then they pay us shyt for our input.
Mostly because their energy & fuel strategies are from the ‘60s!
Look forward to the day that plentiful WA sunshine and cheap wall batteries mean I can wave bye bye to them.
Or we finally get some competition.
 
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Very easy to be 100% (other than the odd supercharger use for 10 minutes to grab a coffee) when parked at home most days, and only plugged in on days that the meter says there is significant exporting. I don’t have a storage battery, and I never charge at night.
In fairness I have a 30kw solar array, and although its looks after two tesla, we don’t drive massive distances each day. Generally charge at about 30% of the maximum amps as that avoids importing, and I never charge both at the same time. Works all year round for me.
So, it’s actually not “very easy” to be 100%, because a majority of working-age people need to use their cars during the day (hence will be charging overnight in most cases), and in the capital cities, especially the higher density ones, very few people have solar arrays of 30kW, because roofs are simply not that big and local government controls prevent putting solar panels on certain roof planes.

After a major battle with my local council, I installed the maximum number of panels that my roof can physically accommodate (16) and maxed the power per panel (365W) to maximise production - so my grand total is 5.84kW - less than 20% the size of your system. And I have one of the largest residential solar arrays in my suburb (which, overall, has rooftop solar penetration of 6% of dwellings).

Given all that, and that my wife drives our LEAF to work four times per week, we are still >80% self-powered due to making our house energy efficient and demand-shifting as much as possible.
 
There's Origin Energy "solar optimiser" plan (NSW) that gives 21c/kWh FIT. It's ~29c/kWh flat price though - no off-peak and no discounts, but for decently sized solar system it pays out. I think this is the maximum FIT available right now. Expecting negative bill coming soon :)
I will soon post my comparison of various rateplans in my “Fun with PW2 stats” thread and the results are very interesting. But you are right, 21c FIT is one of the highest FITs available in NSW, but you are wrong that it is only available with a non-ToU rate. You need to click the right buttons to find the ToU rateplan but it exists.
 
I have calculated for my system that the PW2 has a round-trip efficiency of 93.5%. I reckon that’s pretty good.
If it is 93.5%, that IS pretty good.
I will look at my stats and see if it is as good as yours.
However, ANY battery losses are doubled when you then charge a second battery from the first.
Energy is lost charging battery one, lost again discharging battery one, and then lost in charging battery two.
A good day is when I am home in the daylight: charge the car from solar once the PW2 is full. THAT feels good.
 
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