Update 6/26/09
I am now tracking my energy usage by reading the meter on a monthly basis. On the energy usage graph below, ‘peak energy’ and ‘offpeak energy’ are direct readings of monthly differences from the PG&E meter. ‘net energy’ is 3x’peak’ + ‘offpeak’ since PG&E charges roughly 3X more for peak energy. ‘Cumulative Energy’ is the sum of ‘net energy’ from the previous months to date. As of Jun 18, I have ~800khw extra that I’ve generated; need to finish the car!!!
Here is an update on my solar generation:
Update 12/19/08
From 11/18/08 – 12/18/08, both the energy generated and total amount of sun continued to decrease. We had quite a few rainy days during this period. We should start to see it increase in the coming months.
Update 11/19/08
From 10/18/08 – 11/18/08, though the system was exposed to the same amount of sun, the energy generated continued to decrease.
Update 10/23/08
From 9/19/08 – 10/17/08 (~29 days), 430 kwh was generated with 322h of sun and 732 lbs of CO2 saved.
This means: 14.8 kwh/day, 11.1 hours of sun/day, and 25 lbs of CO2 saved/day.
It looks like the performance is a little less than the avg from previous 8 months as we get into the fall and winter.
Update 10/3/08
From 1/18/08 – 9/19/08 (~240 days)
The 3.6 KW system has generated 4157 kwh of energy, the system saw 3019 hours of sun, and saved 7067 lbs of CO2.
This equates to:
- approximately 3019/240 = 12.6 hours of sun per day.
- approximately 4157/240= 17 kwh of energy generated per day
- approximately 7067/240 = 29.4 lbs of CO2 saved per day
- approximately 4157/3019 = 1.38 kwh/hour of sun.
- approximately 1.38/3.6 = 38% efficient
I plan on updating this blog with details of my solar panel array and track its performance over time… Stay tuned…
In the meantime, here are pictures of the inverter (converts the generated DC energy to AC current for use), the solar arrays on the roof, and the electric meter spinning backwards at 1.47kw per hour in the middle of the afternoon.
If you zoom into the inverter pictures, you can will see that it reports that the system has generated 3656kwh of energy and saved 6214 lbs of CO2 since the system went online (Jan 18, 2008).
