Projects
October 4th, 2009
solar array
This is a Solar Story that occured in Livermore, California. The owner of the house, Bill Turnquist, decided that it was time to add solar renewable energy to his home. After much thought and design he finally put the plan into action using Automation Solar, a local solar solutions company that specializes in residential and commercial solar projects. Here is his Story:
Considerations and design criteria
In early 2009 we began to consider a PV solar system for our 3500 sq ft home in the Bay Area in CA. Previous electric bills in previous summers had run as high as $750 for 2400 KWH usage in a normal 30-31 day billing cycle.
We have two AC units for our two story home, one pool motor pumping a solar pool water heating system, a saltwater fish tank system with chiller, two fountains and a shear decent motor in the pool run randomly. This all amounts to considerable load on a warm summer day. For this reason we elected to install a 7.35 KW system.
Decision and Installation
We interviewed several solar installers, some of which were less than informative, finally making a decision on Automation Solar. They worked with us on the configuration we requested as well as working well with the city tying in the system to the grid without unsightly conduits along the roof. The solar system was installed generally out of sight on the second story tile roof facing southwest at about 27 degrees.
In addition Automation Solar worked with us in selecting/obtaining Enphase micro-inverters. We choose this option for several reasons. First was the improved over-all performance with micro-inverters and second is the ability to monitor every single panel as required to ensure top performance and trouble shooting if necessary. These inverters begin producing earlier in the day and continue to later in the day as compared to a conventional single inverter. They also allow the system to maintain peak performance when a panel is shaded due to a chimney and/or future tree growth.
We also installed the system 6+ inches above the tile roof, giving the system enhanced cooling on hot days when PV performance drops off.
Presently we are on time of day metering and a 12 month billing cycle. After the first year we will re-evaluate the rate schedules and decide whether or not to continue to utilize time of day metering. Our usage is based on someone home at all times, so power running AC units, etc is consumed during peak hours on weekdays.