2013: Solar Project

A Little History


In 2001, the darling wife (DW) and I purchased a 5th Wheel Trailer to start a life of travel and leisure. For one of our early voyages, we planned on spending a week or two dry-camping at a friends unimproved parcel in South Lake Tahoe. Since we did not want to deal with a noisy generator, this so provided me an excuse er, opportunity to install my first solar photovoltaic system. The solar PV system worked flawlessly. By day our six golf cart batteries charged and at night we watched satellite TV while eating microwaved popcorn. Life was good. (For more about that, see our Lake Tahoe trip.)

A few years later I started moving the trailer system to our home when we were not traveling. In fact, the web server which hosts this page was powered for years by our trailer PV system. Years later we decided to obtain a larger system to meet most of our home needs. After much research, I concluded that an AC (alternating current) solar PV system would best make me happy. After careful analysis and begging, my DW approved this endeavor.

Comfort and expense reduction were our motivators for installing solar. Carolyn uses an electric heater under her desk during the day to reduce our central heater usage in the cold months. Doing so does not overheat our home, providing me a cooler retreat in other sections of the house. Additionally, since we are both hi-tech industry veterans, our PCs with extra monitors are typically on all day, along with a large-screen TV in the background. And the web server and hot tub both run 24 hours a day. Our typical electrical usage averages 30 kilowatt-hours a day. This works out to $140 to $225 per month depending on the time of year. During the summer months we rarely use air conditioning, but we still manage to reach PG&Es forth price tier.

I spoke with many solar companies and installers. I went through a long selection process due to the solution I wanted. In the past, I had scrutinized solar ownership cost benefits while appraising real estate. Plus I learned a lot installing my small system. From these experiences I knew the home-ownership benefits and some of the tradeoffs. The large well-known companies all claimed to have the perfect solution for me (translation: the perfect solution for THEM, i.e.$$. So, into the lily pond I swam, kissing many a toad...

Typical solar PV systems connect roof-mounted panels to a central inverter. This solution is commonly called a DC string or string array. DC string array efficiency is compromised by shade, wiring losses and other factors. Additionally, most solar panel manufacturers offer 25-year warranties for their panels; whereas the third-party central inverters typically have a 10- or 15-year warranty.

SunPower 'ACPV' panel with SolarBridge microinverter

The technology I wanted was an AC system integrated with a small inverter on each panel. This solution is called an ACPV system. A few years ago SunPower started producing ACPV products with their full a 25-year warranty for both the panels and inverters. The microinverters are SolarBridge Pantheon II's, integrated with the panels at the SunPower factory. Additionally, they use the SolarBridge monitor system (big brother is watching...)

I knew what I wanted...