Going Solar, a journey in itself

In 2006, prompted by a friend's decision to put solar panels on her house, by the movie "An Inconvenient Truth" and by Carol's strong desire to make changes that would lessen our impact on the environment, we began the process of going solar.  That meant placing solar electric (photovoltaic, PV) panels on our roof.

We did some reading online and found that a good first step would be to get a copy of our electrical use for the most recent full year from our utility, Southern California Edison, in central Orange County, California.  Edison sent us an email with the information, which showed that our total usage for 2005 was 10,278 kWh, an average of 28.2 kWh per day, for which we were charged $1,577 for the year. (By the way, we have a four bedroom tract home, gas water heat, furnace and dryer, no air conditioning, electric cooking, five TVs, four in regular use, one computer tower with flat screen and one laptop, two fountains and a ceiling fan that are always on, and one 21 cuft refrigerator that is 20 years old (subject of a later post).)

We found three companies that offered solar PV installations.  I won't mention the names of the companies for reasons I'll explain later, but I will go into detail if you need it and comment on the blog.  Each of the companies sent a sales person to our house for a two hour presentation.  We compared the price quotes from the three companies and tried to get a sense of the companies' length of experience, customer lists, and judged the presentations and the salesmen on their qualities.  The quotes were fairly similar, but we were able to select one company that gave us the best feelings after weighing all of the information.

Size of project:  We were advised by the salesmen to size the project so that we would replace 80% of our annual electrical usage. That system would produce 8,222 kWh of AC power per year.  Using tools they had that were based on our home's location, the exact compass direction our roof faces and the slope angle of the roof, they guided us toward a system sized at about 5,000 watts DC.  That means that the total rated DC Watts of maximum output of all of the panels on our roof would add up to 5,000.  We chose a system of 24 Sunpower panels, each rated at 215 Watts DC, about 5,120 Watts.  This was the maximum number of panels that would fit on our master bedroom roof, the highest output per panel that was available at the time, and an output that could be handled by the system's inverter.  The theoretical output of this system was 8.724 kWh per year.  We knew that this was a bit larger than it had to be, but this was okay with us because we thought we might buy a plug-in car at some future time, or add air conditioning.

Cost and credits:  The retail price of the chosen system, including labor and permits, was $39,336.  We were eligible for a rebate of $11,837 from the California Solar Initiative, and up to $2,000 as a federal tax credit.  So our out-of-pocket final cost for the system came to $25,499.  Based on our 2005/2006 annual electrical costs, our payback period is $25,499 / $1,577 per year, equal to 16 years, not including the lost opportunity cost of the investment.  However, energy rates are going nowhere but upward, so our system will pay for itself much sooner than that.

Other decision points:
Timing and choice of panels: Our chosen installer could have installed the system in the Fall of 2006, but the panels available would have been Sharp panels, with output rated at about 170 Watts per panel.  We preferred the look and reputation of Sunpower panels, rated at 215 Watts per panel, but due to worldwide demand, they would not be available until early 2007.  We chose to wait for the Sunpower panels, but that turned out to have an impact on our tax credits, as I will explain in the next blog post.

Roofing type:  We have a Mexican tile roof.  We were told by the salesmen that this would not be a problem. Our chosen installer has a policy for tile roofs of removing the tiles in the area of the panels, installing a composition tile roof in that area, and installing the PV panels over the new composition roof.  The roof looks as if the PV panels are "inset" into the surface of the roof, surrounded by the remaining tiles.  This made sense to us, and due to the "low rise" appearance, was preferred by our HOA's architectural control committee.  But it had consequences that I'll cover in the next blog post.

Our Utility:  It was recommended that we enter into an agreement with our utility, SCE, called a Net Metering Agreement for Grid-Tied Systems.  Our system is grid-tied because when our system makes more power than we are using at the time, it sends power to the electrical grid.  When we are using more power than our system is making, our house draws power from the grid.  In that way, our electrical meter will run backwards and forwards, depending on our power output and consumption. With a Net Metering Agreement, our meter is read each month, but we are only charged for our electricity once per year, on the Net Metering Anniversary.  As I will explain later, we have never paid an electrical bill since the system was installed because we have always made more power than we use.

Community Association (HOA):  We live in a HOA (homeowners' association), with architectural rules that govern home modifications that are visible from outside the home.  We submitted the required forms and got approval for our PV project.  We had to answer many questions about the materials to be used, the finished appearance of the home, etc.  We provided photographs of our home and our roof and added a drawing of the final panels as they would be installed.  They wanted to know why we couldn't place the panels flat on our patio cover (reduced performance due to flat angle to the sun and too much shading on our patio).  We also gave them a copy of the California Solar Rights Act which prohibits HOAs from denying the right to add solar panels without good reason.  By being well informed, we were able to get approval after one meeting.

We signed the agreement with our selected installer and awaited the installation in January of 2007.

More about our solar journey in the next entry.