In the latest billing period the average production per day is up to about 7.8 kWh
The best day was march 23rd, but there was still some cloud that day. We havent had a day with zero clouds all month.
My daily commute is 28 miles and uses about 7.5 kWh per day, but thats only 5 days a week. The solar panels every day produce enough energy for a 28 mile drive.
But there is more to the story. Since getting the solar panels, I’ve been aggressively conserving electricity. I already had CFLs in many places, but I have put in LEDs as well in every room we regularly use. I am diligent about turning things off when not in use, but especially when they are incandescent bulbs. We also upgraded the attic and crawlspace insulation and sealed the heating ductwork. The ductwork had leaky joints and we were wasting tons of heat into the crawlspace under the house.
The March 2010 electricity bill was 34.17 kWh per day.
The March 2011 electricity bill is 21.72 kWh per day. ( and it was 2 degrees colder in 2011 )
Our total usage was about 26 kWh per day ( because some of it was offset by using the energy produced by our panels – but when the meter actually goes backward it makes the statement more complex. ).
So the energy use per day is about 8.17 kWh less than the last year.
That alone is enough to completely power the Tesla. Instead of being a car powered by the sun, it is actually a car powered by turning off waste.