What shall we do to celebrate our solar PV system's 4th birthday? While cake is always appropriate (usually chocolate in our family), we thought a blog to give you more details of it's performance would be even better. We'd like to see solar arrays multiplying on everyone's roof after all!
According to Solar City, the company that installed our system and provides a very informative computerized monitoring, after four years, we have officially offset 21,593 pounds of CO2, the equivalent of planting 10.3 mature trees. That's quite a forest on our little lot in San Francisco!
Here are some intersting graphs from Solar City:
The first shows a typical year, month by month starting in January. In all four years, May has been our best month, generating between 472 and 503 kWh. July and August take a little dip as we do live on the foggy side of town, but as you can see, there is still plenty of electricity being generated during those months as well.
The next graph, shows a beautiful curve of the path of the sun, this particular day being June 30, 2010, which has so far been our record day with 20.41 kWh generated.
Did we mention that we only paid $29 upfront for our system on a lease basis and that we've saved money from Day 1? Well, we did, but it's been a while. You can see the details of our solar lease on our early blog post from 2008. Boles Solar Lease info
Our monthy cost for the lease is now a whopping $32 (and will rise to $36 over the 15 year term), and our net savings are about $60 per month, not counting the rise in PG&E rates over the past four years. GO SOLAR! Prices of panels have come down considerably in the past few years and there are great deals out there to save you money and save the planet some unnecesary CO2.