Please help me w/ the basics.

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Hello,

I live near Atlanta, Georgia. I am interested to learn the basic of solar power.
I bought 3 sets of solar rechargeable shed light from Northern Tools. Cost me $39 each.
The light is not so bright but I think it can still be usefull during emergency. We
can use these lights when theres a tornado warning or when
power is out. But the box says the light can only last 50min to 70min, when being used
continuously.
So I am very curious about just how to power qty 3 20watt or 40watt light bulb down my
basement. I would like to get light during whole night time & let it charge when not in use
or during the daytime.
So I would like at least 8hours worth of light (continuous use) if possible.
Is this possible?
If yes, what do I need to make this possible?

Summary...I would like some advice on how to...
Power qty. 2 or 3 (40watt) light bulb = 8hours continuous use.
For lighting down my basement during regular use or during emergency.
I also need a list of all the materials I need & all the connections/installation.

Pls. forgive all my questions, I am very new at this

Thank you for taking time
REJO1

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,479 admin
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    Re: Please help me w/ the basics.

    First, I would work on conservation--changing from standard incandescent bulbs to CPFL or LED will cut down your electricity requirements by 2/3 to 3/4's...

    For example you can get a 7 watt CPFL light that is equivalent to a 20 watt bulb. LED's would also be similar savings--but you would have to make sure that you can use their light (tends to be more focused than CPFL's would be). CPFL's, LED's, and others are available in both 12 VDC and 120 VAC:

    www.ledtronics.com/markets/25mm_med_index.htm
    www.superbrightleds.com/edison.html
    http://www.kansaswindpower.net/led_lights.htm
    http://superbrightleds.com/other_bulbs.htm 6v and 12 vdc candelabra base (small screw base)
    http://www.oksolar.com/n_cart/search.asp?cat=Lighting&subcat=Light%20Bulbs Whole bunch of LED (12, 24, 120 etc) and 12vdc CPFL, and others (contact vendor for specs on glass bulbs with LED "guts")
    http://www.ccrane.com/lights/led-light-bulbs/index.aspx C Crane LED "bulb" page (many types of screw base bulbs available)

    You can also get LED Flashlights, CPFL Flashlights/Lanterns, and Replacement Flashlight bulbs...

    http://www.brightguy.com/ (good selection of high quality LED lamps and, usually, good price)

    Even Costco sells a CPFL 4x D Cell that will last many hours (I forgot how may) of nice area lighting (got one for my Mom's senior apartment which seems to lose power pretty often (just her building, nowhere else).

    There are many things you can do, and all have their advantages and disadvantages...

    Questions:

    Do you want AC power for other things (radio, TV, medical equipment, cooking)
    Is this for short term or long term outages (short term, light for 1 day, long term would be week or months without power)
    Do you want something portable (flashlights can be taken to shelter, large systems can't)
    Do you need lots of light, or just "mood" lighting until the even is over
    Do you want to avoid maintenance
    Do you want this to be the beginning of a grid-tied solar or off-grid solar system

    So, to get started, look at replacing the bulbs in the solar lighting with LEDs--Even Target now-a-days has standard LED flashlight bulbs (2D-6D voltage), that will last for 100 hours with 3 D alkaline cells (regulated, not too bright but for 100 hours, not bad) or even mini-mag conversion LEDs that will last 10 hours on 2x AA batteries.

    Rechargeable batteries are OK--but, generally, they need to be kept charged and will not last forever (especially if the charger is not very good). Alkaline will last 5 years in a cool/dry place.

    Rechargeables (lead acid) though are good for supplying more power at lower costs... A car sized storage battery (don't use a car battery--they are not intended for deep cycling discharging) can supply, for example, about 50 watts for 10 hours. But the battery will need a good charger, and would probably last around 5-7 years. AGM (sealed lead acids) cost more, but have much less maintenance required. All will need good ventilation as they give off hydrogen gas when charging. Also need to be protected from children (acid, high current if shorted).

    Solar PV charging systems are great (I have Solar Grid-Tie system for my home), but have issues... A standard solar grid-tied unit will not work if the power is out. Off-Grid systems work well, but are not cheap, and if you get hit by a tornado, the panels are probably going to be gone/damaged anyway...

    Generator--If you have natural gas or propane, they are pretty cheap to buy and install... One issue is that the Home Emergency Generators are typically pretty large, and even just to power one nighlight may use $0.50 to $1.00 of fuel per hour (at full load, they may use twice as much fuel).

    If you can get away with a small generator (1-2 kWatt), the Honda eu1000i and eu2000i are pretty hard to beat. The eu2000i will (very) quietly (you can talk quietly next to a running eu* generator) supply 400 watts about 15 hour (or 1,600 watts for 4 hours) on 1.1 gallons of gasoline (several places will sell for under $900 shipped to your door). Obviously, there are issues with storing gasoline (6-12 months with stabilizer additives)--so that is not for everyone. And you have to make sure the carbon monoxide from the generator does not get into homes/rooms--deadly. The large (but cheap) 3-5 kW generators are extremely noisy (if you are in a suburb or city--the noise may be unbearable to neighbors and yourself) and fuel hungry (maybe 5x the fuel burn of the Honda). Again, conservation can stretch 5 gallons of fuel for 5 days, vs 5 gallons of fuel per day for the cheaper/larger portable generators.

    Sorry to type so much--but you have a lot of options and just need to determine what your needs are. Treat this like camping--get a small stove, some freeze dried and/or canned food, water storage, and flashlights (LED/CPFL with a pack of batteries from Walmart/Costco) as a start.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
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    Re: Please help me w/ the basics.
    So I am very curious about just how to power qty 3 20watt or 40watt light bulb down my basement. I would like to get light during whole night time & let it charge when not in use or during the daytime. So I would like at least 8hours worth of light (continuous use) if possible. Is this possible? If yes, what do I need to make this possible?

    Summary...I would like some advice on how to... Power qty. 2 or 3 (40watt) light bulb = 8hours continuous use. For lighting down my basement during regular use or during emergency.

    This will be a good project to learn about some of the basics. I agree with Bill that the place to start is with conservation. So, let’s plan on using DC CFL’s, which will eliminate inverter inefficiency and use less energy than regular ol’ incandescent bulbs.

    Also, to light the basement all night during the winter, you’ll need to run the lights for perhaps 14 hours. So, two each 12 V ~ 7 W CFL’s for 14 hours will require 2 x (7 W / 12 V) x 14 hours/day = 16.3 Ah/day.

    To run the lights for three nights during three days of autonomy (bad weather; essentially no Sun) and not discharge the battery below 50% SOC, you’ll need a battery rated at 16.3 Ah/day x 3 days / 50% = ~100 Ah. A Group 27 size 12 V battery AGM battery from Deka/East Penn or MK would work nicely.

    NREL data for Atlanta indicates that a south-facing PV array tilted up at latitude plus 15 degrees (= ~49 degrees) will collect a average of 3.9 hours / day of insolation during December, the worst month. Assuming AGM battery coulombic efficiency of 98%, the PV array will need to be rated at ((16.3 Ah/day) / 98%)) / 3.9 hours/day = 4.3 A. Assuming a Vmp of 17 V, this would require a PV module rated at 4.3 A x 17 V  = 73 W STC. A Kyocera KC85TS PV module should work nicely and provide a bit of a safety factor. (Note that Summer insolation and longer days will allow you to run more lights and/or other small loads from the same system.)

    The perhaps ideal solar charge controller for your system would be the MorningStar SunLight SL-10-12 unit. Using a combination of the PV module and stored sunrise and sunset data, it can both charge the battery correctly and automatically turn the lights on at dusk and off at dawn. The controller should be mounted near the battery to provide for effective temperature compensation.
    I also need a list of all the materials I need & all the connections/installation.

    Sorry, but you'll have to do some of the work yourself. The basics are described above, and the parts described are available on-line. (Hint #1: Start with NAWS on-line store. Hint #2: The manual for the MorningStar controller can be downloaded from their website). Don't forget fuses.

    Good luck!
    Jim / crewzer
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
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    Re: Please help me w/ the basics.

    i'll say what i've got to say in short order. in general bill and jim are correct in going conservative. you may find the leds will suffice like night lights and draw little power from your battery. typically 15 to 20 milliamps for a small white led rated for 30ma as beyond this a thermal runaway event occurs. this will have to be either a commercially made fixture that accomodates your the battery voltage or done yourself with a dropping resistor calculated properly to keep the current low. no inverter is needed for this.
    the compact flourescents should be low wattage as stated, but observe if that wattage level will serve you properly in whatever you wish to be lit with my suggestion of keeping them at 12vdc instead of an inverter. these cfls can be switched off to save power while leaving the leds on for the most basic light until the need arrises for more light.
    anything you do should be aimed at 12vdc operations if possible and 110vac needs require an inverter with a larger consumption due to the process of converting or inverting more specifically to 110vac. any 110vac motors along with portable power tools with batteries and many wal wort items will require that it be a sinewave inverter thusly boosting costs considerably.