Solar Photovoltaic Collection for Residences
What is PV?

Photovoltaic conversion of the sun's radiation is commonly referred to as PV. It converts light energy into low voltage electrical power in DC, or higher voltage electrical power in AC (with the help of other electronic equipment).
Solar Photovoltaic Collection in Residential Applications--
Photovoltaic translates to voltage from a light source. And even low light and cloudy days can produce electric energy, although at much reduced amperage (flow of electrons). Also called "PV," one of its best claims to fame is that it has no moving parts—just moving electrons.
Sunlight strikes a silicone based wafer and excites its electrons which travel past a substrate to a semi-conductor below. In the process, an electrical charge is generated between the positive and negative terminals of the wafer's "sandwich." Typically, wafers are wired in series inside a collector panel to produce their amperage (flow) in the 12 volt range.
Devices that take such power and convert it to higher voltages typical to household or commercial transmission lines are called inverters. Those familiar with Ohm's Law know that line losses are least with high voltage transmission—so inverters and other electronics are necessary to make PV a commercially adaptable product. But no moving parts and no need for water are powerful advantages for PV over solar thermal in large, commercial arrays in deserts. Panels can be mounted in a fixed orientation on the ground or on roofs, and (residentially) can also be mounted on poles for tracking the sun's arc across the sky throughout the day.
Sunlight strikes a silicone based wafer and excites its electrons which travel past a substrate to a semi-conductor below. In the process, an electrical charge is generated between the positive and negative terminals of the wafer's "sandwich." Typically, wafers are wired in series inside a collector panel to produce their amperage (flow) in the 12 volt range.
Devices that take such power and convert it to higher voltages typical to household or commercial transmission lines are called inverters. Those familiar with Ohm's Law know that line losses are least with high voltage transmission—so inverters and other electronics are necessary to make PV a commercially adaptable product. But no moving parts and no need for water are powerful advantages for PV over solar thermal in large, commercial arrays in deserts. Panels can be mounted in a fixed orientation on the ground or on roofs, and (residentially) can also be mounted on poles for tracking the sun's arc across the sky throughout the day.
PV power can be captured as DC (direct current) electricity and stored in batteries, and this power can be "inverted" to AC (alternating current) as needed. This is popular in off-grid homes and buildings. But, a system within the "grid's territory" can operate with a battery bank and be inter-tied to the utility, or it can do the same thing without the batteries. The grid is capable as serving as your "battery." This operation will turn your meter backward when exporting power to the utility and forward when importing power from your utility. These arrangements are covered by connection safety policies by your utility and by your state's net metering law (if your state has passed such legislation).
The data below represents the daily collection of a 3.5KW—18 panel, utility inter-tied system in Quincy, CA for September 1, 2011.. The day's "catch" is shown in each of the blue panels. Other summary tables show the monthly collection for January, June, and August, 2011. Units are in kilowatt hours of electrical power.
Click on these images to enlarge them--
The data below represents the daily collection of a 3.5KW—18 panel, utility inter-tied system in Quincy, CA for September 1, 2011.. The day's "catch" is shown in each of the blue panels. Other summary tables show the monthly collection for January, June, and August, 2011. Units are in kilowatt hours of electrical power.
Click on these images to enlarge them--
From a customer's point of view, "zeroing out" would mean that enough solar-based electricity would be collected and pushed back onto the utility's lines throughout the year so that all the power consumed would be balanced with power produced. There would be no annual cost for electricity. Net metering varies by location. Click on the links below.
Net Metering Laws in California Net Metering Laws by State
An argument can be attempted which says that the place for PV is on residential rooftops. With net metering providing a pathway for excess power back onto the grid, several things happen (all good). Renewable power is generated exactly where it is used—your house or neighborhood. And no long-distance transmission lines or new substations need to be built to get you that power. This avoids charging all ratepayers for high voltage, long distance transmitted solar power.
Net Metering Laws in California Net Metering Laws by State
An argument can be attempted which says that the place for PV is on residential rooftops. With net metering providing a pathway for excess power back onto the grid, several things happen (all good). Renewable power is generated exactly where it is used—your house or neighborhood. And no long-distance transmission lines or new substations need to be built to get you that power. This avoids charging all ratepayers for high voltage, long distance transmitted solar power.
What's involved in high voltage transmission--
The gallery below (click on image for larger version and caption) shows the Celilo, OR to Sylmar, CA direct current, DC line. 800+ miles through the deserts of eastern Oregon, western Nevada, and eastern California without a subdivision branch. This line carried 750,000 volts when these photos where taken in 1982 and now carries over one million volts. As DC, it has a 3% loss rate compared to the 7% losses in AC transmission. It exports surplus hydro power from the Columbia River to the power-hungry market of southern California.
The gallery below (click on image for larger version and caption) shows the Celilo, OR to Sylmar, CA direct current, DC line. 800+ miles through the deserts of eastern Oregon, western Nevada, and eastern California without a subdivision branch. This line carried 750,000 volts when these photos where taken in 1982 and now carries over one million volts. As DC, it has a 3% loss rate compared to the 7% losses in AC transmission. It exports surplus hydro power from the Columbia River to the power-hungry market of southern California.
Click on these images to enlarge them--
Green Energy (PV) Businesses--
Businesses that install photovoltaic solar are multiplying. More PV is a good thing for us all, and it's good to see the market growing among residential users. One example of the consumer friendly posture of such businesses is represented in the gallery below. The company is Solar City in California.
Click on these images to enlarge them--
Solar City has a home page with a very commercial look and feel. It conveys a clear posture to the consumer, and invites exploration without the fear that such investigation will automatically produce five more annoying, unwanted commercial calls at dinnertime.
I tried the calculator for my home's $40/mo shoulder season electric bill with Pacific Gas and Electric and you can see the result in the third frame (above). To get that, their Web page prompted me for my zip code, street address, percent shading of my roof (between two choices) and my roof's pitch. It performed calculations off-site and immediately reported the results you see in the third frame.
Consumers need numerical information to make an informed decision. I am pleased that this Web site allows a quick numerical results for a potential residential PV installation. This should help knock down barriers facing consumers to investigate this technology without having that dreaded feeling of just having walked onto a used car sales lot. One note of potential caution based on no interaction with this company to justify it. Solar City offers other services such as technical energy audits with blower doors and other instrumentation. I know neither what those services cost nor the role they play in the eventual results/recommendations from this company to the clients. But a note of caution may be in order.
Having taught personal finance for many years I will reflect on a possible parallel concern with the example above. When a consumer of personal financial planning goes to a stock brokerage or insurance agent for retirement advice they can get it for free. But strangely, the "solutions" to their personal financial plan often become a straight purchase of recommended stock shares or life insurance products. The alternative track is a "fee for service" financial planner who is not a sales person or does not receive a commission on the product they recommend that you buy. This avoids a conflict of interest on their part.
Again, I don't mean to cast a suspicious light on Solar City. I only remind that Caveat Emptor is required when the solution to your energy needs might all be centered on products that are sold by the same people performing the "analysis." Still, it seems that Solar City is out front about mathematical analysis (which is very good), and one finds similar situations all over the business/service scene without the math, every day. Plumbers, building contractors, grocers, mechanics, travel agents, and many others put you in the same boat. As long as sales euphoria is largely absent and the numerical forecast looks good, such a PV purchase might make more sense for you than any other.
A VERY SUBJECTIVE NOTE: In my continuing review of PV-electricity and displaced utility power via net metering I observe that those who will benefit most are those with current high bills, provided they don't over-size their PV installation. These folks will save the most money (though they may have been consuming some kilowatthours they could have avoided) because their bills were high, perhaps in the upper (more costly) tiers of their utility's rate schedule. Billing in even one tier lower can be a large savings in itself. It's ironic how the super-conservative users of electricity have the least to gain from a renewable installation. But at least as of this writing, there are many more high residential kwh users than low ones, so there is room for lots of savings through PV installations.
I tried the calculator for my home's $40/mo shoulder season electric bill with Pacific Gas and Electric and you can see the result in the third frame (above). To get that, their Web page prompted me for my zip code, street address, percent shading of my roof (between two choices) and my roof's pitch. It performed calculations off-site and immediately reported the results you see in the third frame.
Consumers need numerical information to make an informed decision. I am pleased that this Web site allows a quick numerical results for a potential residential PV installation. This should help knock down barriers facing consumers to investigate this technology without having that dreaded feeling of just having walked onto a used car sales lot. One note of potential caution based on no interaction with this company to justify it. Solar City offers other services such as technical energy audits with blower doors and other instrumentation. I know neither what those services cost nor the role they play in the eventual results/recommendations from this company to the clients. But a note of caution may be in order.
Having taught personal finance for many years I will reflect on a possible parallel concern with the example above. When a consumer of personal financial planning goes to a stock brokerage or insurance agent for retirement advice they can get it for free. But strangely, the "solutions" to their personal financial plan often become a straight purchase of recommended stock shares or life insurance products. The alternative track is a "fee for service" financial planner who is not a sales person or does not receive a commission on the product they recommend that you buy. This avoids a conflict of interest on their part.
Again, I don't mean to cast a suspicious light on Solar City. I only remind that Caveat Emptor is required when the solution to your energy needs might all be centered on products that are sold by the same people performing the "analysis." Still, it seems that Solar City is out front about mathematical analysis (which is very good), and one finds similar situations all over the business/service scene without the math, every day. Plumbers, building contractors, grocers, mechanics, travel agents, and many others put you in the same boat. As long as sales euphoria is largely absent and the numerical forecast looks good, such a PV purchase might make more sense for you than any other.
A VERY SUBJECTIVE NOTE: In my continuing review of PV-electricity and displaced utility power via net metering I observe that those who will benefit most are those with current high bills, provided they don't over-size their PV installation. These folks will save the most money (though they may have been consuming some kilowatthours they could have avoided) because their bills were high, perhaps in the upper (more costly) tiers of their utility's rate schedule. Billing in even one tier lower can be a large savings in itself. It's ironic how the super-conservative users of electricity have the least to gain from a renewable installation. But at least as of this writing, there are many more high residential kwh users than low ones, so there is room for lots of savings through PV installations.
Solar Photovoltaic Collection in Commercial Applications--
Horton Tire Center, Quincy, CA
This commercial facility is the local Les Schwab tire affiliate and a 27KW PV system was installed there in 2010. The gallery below shows the roof mounting of panels, micro and larger inverters, and the net metering. When this meter photo was taken at 3pm, Solar Time, the shop was in full operation and the net push-back onto the utility grid was close to 18,000 watts.
This commercial facility is the local Les Schwab tire affiliate and a 27KW PV system was installed there in 2010. The gallery below shows the roof mounting of panels, micro and larger inverters, and the net metering. When this meter photo was taken at 3pm, Solar Time, the shop was in full operation and the net push-back onto the utility grid was close to 18,000 watts.
Click on these images to enlarge them--
Intel Corporation's Folsom, CA facility
This very large corporation has electronic component plants in several locations across the United States. Their 1.1 Megawatt PV installation is visible to thousands of drivers along U.S. Hwy 50, east of Sacramento, CA. Therefore, it serves as a daily reminder that electricity from renewables is real, functional, and cost effective. For deeper thinkers, it can also suggest that distributed PV scale of this magnitude scattered closer to us diminishes the need for desert-generated power transmitted over long distance on new, expensive high voltage lines.
Click on these gallery images to enlarge them and see captions— Forget the stills— Show Me The Movie!
Then use left and right arrows to scroll through the set
Then use left and right arrows to scroll through the set
Solar-covered parking lot in downtown Las Vegas
What do you need in a paved area in a 3100+ degree day climate? You need shade, and plenty of it. Why not make hay while the sun shines? This covered parking lot generates plenty of power while saving the paint and upholstery of the cars driven by workers at the Desert Research Institute in downtown Las Vegas (which is also the location for the National Atomic Museum, telling the story of the Nevada and New Mexico test sites for the Manhattan Project that ended WWII in the Pacific theater)
Click on these images to enlarge them and see captions—
Then use left and right arrows to scroll through the set
Then use left and right arrows to scroll through the set