Our 6.5kW solar system generates about 43kWh this time of the year and "clips" to 5kW from about 10:30-14:30.
I hate, with a passion, giving Synergy any of my "juice" for about a quarter of what they charge me to buy it back, 7cents vs 28cents
To this end, when the car is home during the day, fortunately more often than not, I can dial down to 5A 3P charge rate which is about 3.5kW. This lets me run our house, including two split systems air-cons from solar and hang around the 5kW inverter cap. We'd rather pay for a little extra power than give it away. We use the washing machine and dishwasher from about 08:00-09:30 and then put the car on. This equates to about 15kms/hr of added range for 70-90kms per day. If my wife takes the car to her work they have 32A 3P EV charging run from solar too.
Our last 60 day power bill was $105 to run a family of four household INCLUDING running a Tesla Model X
Here's a usage graph for our house last Monday. At our feed in tariff you need 4x the green area under the curve to offset the grey area above the green curve.
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BTW, Synergy offers an EV tariff which is a 30% discount between 23:00-04:00hrs which I never use to charge the car. When we finally ever get our Powerwall 2 I might use that off peak discount juice to top up the battery in winter. As you can see from the excess green in the above graph, I have heaps of spare juice to put into a 13.5kWh Powerwall 2.
IMHO, Synergy should be offering a much cheaper nightly EV tariff. Here is a link to the daily half hour MWh price. Click on 2019 and download the spreadsheet and then scroll to the current period. For example, for 01:00-05:30, the MWh price is $27/MW 1/2 hour.
Market Data
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