Ah the saga of solar. Several people have asked about our solar system so I thought I would give you the whole tour.
The wife and I are trying to plan our retirement and would like to be able to maintain our home at a fixed cost and in a sustainable manor. We had electric bills well over $4000 annually and natural gas bills of about $800 annually. Really untenable on a fixed income. We decided to research what we could do to reduce our output from a capitalist view (mine) and a carbon footprint view (hers).
In the fall of 2009 we heard that the Federal government (American Recovery and Reinvestment Act of 2009) was going to increase the solar tax credit to 30% of the actual cost with no caps on the expenditure for the tax years 2010-2016. We also found that the state offered a $1000 tax credit and our utility would rebate us $3 a watt for a solar PV install. We went to our utility and pulled our annual usage from a page they offered on their web site. We researched a couple of lease programs and found they really didn't lower our costs that much and none of the tax benefits would be ours. We started taking bids for a purchase of a full blown solar system. Some sales guys didn't seem to get it, and offered partial systems. We finally got someone to sit down and look at our total usage and agreed that with our goal of net zero electric bill a couple things needed to happen.
1) We needed to conserve on our usage.
2) we needed to scale a system that could easily have some head room for expansion.
On the conservation side our old AC units had to go, as luck would have it, the large one blew a compressor as we were talking to our AC contractor about a replacement. Ah the Feds to the rescue again, the same law that allowed a tax credit for solar also allowed for a $1500 tax credit on cooling system improvements. Again we took advantage of the tax situation. We eventually replaced both 10 seer AC units with 17 seer. We also took advantage of some other credits & rebates from the state and utility and replace our 15 year old fridge & freezer units with energy star and hit Lowes on a 20% off sale and a 10% off coupon . We did a mass change out of incandescent bulbs for CFL's and are gradually changing them out with LEDs as price and opportunity allow.
As for system scaling that was a bigger issue. Our solar contractor suggested that a 8,000 watt setup would do the trick. My calculations showed that about a 10,000-12,000 watt system was required and we did have a Volt in the back of our minds even then. We compromised sort of. Initially we installed the 10,000 watt setup but insisted that the electronics package be large enough to add 2500 watts of solar panels at a future date. He agreed, and why not it was more dollars in his pocket! We wrote the contract for commissioning in 2010 to qualify for the tax credit, and made a minimal down payment and draw schedule for him as he completed phases of the work.
Now this is where it gets interesting, the permits! The permitting agency in my jurisdiction had never seen a residential solar install that large. There was several revisions of the engineering drawings going back and forth between the engineer and the code monkeys. Finally a cost over run came out of that exchanged, our service entrance would require an upgrade to handle the added capacity that the solar system afforded us. Boom $4300 required. We relented. From there the install was straight forward and progressed to commissioning. That was an interesting day as the utility, code guys and contractor guys were all there for the big switch throwing.
We used the system for about 1 year and did determine that even with our conservation methods if we added a Volt we would need more panels, same contractor for a fair price did the add of 2500 watts. Our submission to the utility was one of the last ones available for the $3 a watt rebate. We will need to watch our usage again when the second volt comes on line this fall. If we need to add again for Volt #2 the rebates are down to $1.45 a watt.
Attached are some pictures of the system.