Solar Electric Power

The principle of Photo-Voltaic or PV power (converting light into electricity) was discovered in 1839 by French physicist Antoine-César Becquerel when he found that sunlight striking a surface can emit electrons^. Some substances emit more electrons than others, and todays PV panels are made primarily of silicon, which is the major component of sand. If 1% of the worlds deserts were converted from sand to solar panels, we could replace all the power supplied by fossil fuels.

It matters: In the USA, more than 70% of electricity is produced by coal, natural gas or oil^. Every home in North America that uses a PV system to supply electrical power removes about 4.3 tons of carbon dioxide from the air each year. That is roughly the same as removing one car from the roads^.

Help, don't Hoard: There are two basic types of home PV systems: ON-grid and OFF-grid.

• OFF-grid systems depend on batteries or other energy storage systems to save the power generated during the day for use at night. Because batteries must be replaced regularly and contain very toxic materials, the OFF-grid systems probably do more harm than good in the long run. Until battery technology catches up to advances in PV panels, or some other energy storage methods such as Hydrogen or compressed air become available, ON-grid systems make more sense (and cents!)
• ON-grid systems don't actually generate power for the home where they are installed! Instead, the power is purchased by the utility company and used at businesses and other day-time power consumers to reduce the load on more traditional power generation plants. After dark, the grid provides power from sources that do not depend on sunlight which could include wind, hydro-electric or nuclear power.

PV is FREE! The cost of converting a home to ON-grid PV power is effectively zero. After state and federal rebates, the value of the home is increased more than the cost of the system, and given a reasonable interest rate to finance the cost, the loan payment will be less than the utility bill savings^. The maximum "bang for the buck" comes when a system is sized so that it does not completely eliminate the power bill, but rather reduces the net energy use into the lowest (and cheapest) tier.

The time is NOW! The price of electricity has increased substantially in the last few years, after holding steady for almost a decade^. If this trend continues, and it seems likely to, PV systems begin to make even more financial as well as environmental sense:

A case study: My own PV system

"Fear" says: "On cloudy days I could get much better performance from my panel with two mirrors set up as above. I still didn't max out my panel, but maybe with more mirrors I can. "

Great care must be taken with mirrors to ensure that sunlight is never concentrated on any of the following:

• The open airspace over your home. Airplanes, helicopters, etc... pilots could be blinded by an unexpected reflection of the sun.
   
• Any surface not able to handle the heat build up. There is also a legal issue... if a fire does start, even if there is doubt that your mirror was the cause, it could easily be cited as a contributing factor.
   
• The street in front of your house. Again, an auto accident could be blamed on your mirrors.
   
• One panel of a multi panel set. Or all but one panel. Grossly uneven coverage can cause power from other lit panels to flow backwards though an unlit panel, heating and damaging it beyond repair.

Also:

• Solar Chimmeny Power Generator
• Sun Powered Turbo Generator Idea by Peter L. Peres

See also:

• http://pvwatts.nrel.gov/pvwatts.php Very good, and apparently quite accurate solar power estimator.
• https://plus.google.com/u/0/+JamesNewton/posts/armRtooupj2 You can buy individual solar cells (not panels, the cells the panels are made of) at very low costs from china, e.g.
  http://www.alibaba.com/product-detail/high-efficiency-156mmx156mm-6-2BB-3BB_1095430687.html
• Soldering entire cells together and mounting them is the labor part. But small panels use /part/ of many cells to get to a usable voltage with less surface area (and less current) and so you ALSO have to break the cell apart, and do more soldering.+
• http://www.resilience.org/stories/2012-09-19/blow-blow-pv-system-efficiency-case-study-storage Superb case study in San Diego showing the disadvantage (and advantage) of battry systems vs grid tied. He gets 62% of the solar energy where his neighbors grid tied system gets about 88%. And he must replace the batteries every 2 to 6 years at a cost of about $1,000 total. On the other hand, he has power when the grid goes down, and grid tied systems do not.
• http://www.residentialsolarpanels.org/plan-solar-system Very nice blog post explaining how to plan a home PV system.
• http://www.rain.org/~philfear/how2solar.html How to Make a (small but useful) Solar Power Generator for Less Than $300
  

  Basic Solar Power Generator
  5-8 hours to charge a dead battery; 1-3 hours to top off a weak one. It will run radios, fans, and small wattage lights all night, or give you about 5 hours of continuous use at 115 volt AC, or about an hour boiling water.

  • 8" x 27" MBC-131 Uni-Solar soft panel 16v Shade tolerant, flexible, light.
    • Rated power (Watts, peak): 5.50
    • Typ. 12 Volt Charging (Amp. Hrs/Wk) 13.00
    • Voltage, Typ. Max Power (Volts) 15.60
    • Current, Typ. Max Power (Amps) .35
    • Weight (pounds) 1.5
  • deep cycle  (not automotive) 12 volt lead/acid battery (in battery box for safety)
  • 10 foot cable with battery ring, terminals, fuse, and convenient 2 pin plug ( cigarette lighter )
  • Optional: 115 volt 140 watt inverter made by Power-to-Go at Pep Boys for $50

• http://www.heliopower.com Very recommended.
• http://www.solarelectricinc.com/ San Diego retail supplier.
  https://www.internetservices.com/secure/solarelectricinc/
• http://www.uni-solar.com/Index.html soft panels. They have no glass glazing, are flexible, unbreakable, and lightweight. They have bypass diodes between every cell, which makes them the only commercial module that is shade tolerant. Nor do they whimp out at high temperatures.
• http://energycenter.org/ContentPage.asp?ContentID=370&SectionID=407 California Solar Initiative. Rebates, incentives, freebies...

Code:

• SPAMnfaubionSPAM at netzero.com shares this code:

  Comment on the statement, "Because batteries must be replaced regularly and contain very toxic materials, the OFF-grid systems probably do more harm than good in the long run. Until battery technology catches up." Look at Thomas Alva Edison "Primary Battery" patent of 1906. It is the Alkaline battery using Nickel/Electrodes. I can provide an article that tells how to collect the pieces and build it. Some are claimed to have worked for over 80 years. Minimal emmisions. Only needs water top-up approx. each 3 weeks. Electrode replacement approx. 10 years. Made from readily available, locally purchased parts 1.5 volts DC per cell. 10 cells=12VDC. 20 cells=24VDC. 40 cells=48VDC. Will completely discharge w/no damage. Will take fast charge without damage. Each cell housed is cheap ex-chemical containers of 20 USGallons. I have complete instructions in MSWord format.

  James Newton of Massmind replies: I would REALLY love to have and publish those instructions. Please email them to me?

  +

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