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Solar Power Question =)

Am I A NOOB?

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  • No

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vbj4

New Member
Hi,
I really have little skillsin electronics at all besides being able to wield a soldering iron. I have been wanting to do a solar project for awhile.

the panel I found specs:
12volt
1260 mw max power
18volts(no-load)
60-70mA

the lights i want to run (around 10 of them?)
3.0-3.5Vdc
20mA

do you think this solar panel would be capable of powering around 10 of those lights. hmm let me rephrase how many estimated hours could i run 1 bulb for?

thanks
 

audioguru

Well-Known Member
Most Helpful Member
A solar panel makes its max output when it is outside on a sunny day, on the equator of earth at noon, when it is pointing directly at the sun.
You didn't mention charging a battery so why have LEDs lighted at noon? For a room without windows?

You would be lucky to light 3 pairs of LEDs (6 in total). They would be fairly bright for a couple of hours around noon on sunny days in summer then pretty dim on other days. Of courrse they won't be lighted at night without having a battery.

Sure you are a NOOB. :lol:
 

vbj4

New Member
battery, i should have put that in there. i want to run it to a 12V car battery to charge and run the lights off the battery.
although running the lights at noon does sound kinda fun ill save that one for my next project. guess i should probably wait to say that until after this project.
 

bryan1

Well-Known Member
vbj4 said:
battery, i should have put that in there. i want to run it to a 12V car battery to charge and run the lights off the battery.
Car batteries are used for what there called starting a car. They aren't suitable for use with a solar cell as they wouldn't last. Look for a deep cycle battery to use and try google and find out about using solar before you waste your time and money. The solar panel you described sounds like a 15 watt panels form the confusing spec's. If you only want to light a few led's sheesh this can be done using a few nimh aa cells and some cheap solar cells from a solar gargen light, but firstly you need to know what your doing.
 

audioguru

Well-Known Member
Most Helpful Member
bryan1 said:
The solar panel you described sounds like a 15 watt panels form the confusing spec's.
It has half the current rating of the 1.8W solar panel that I bought on sale last week. It is early spring now and the sun is about halfway to its max height in the sky and outside the solar panel gave a max of 8V at 35mA. Its output was much less through a window. It is rated for 12V/150mA.

If you only want to light a few led's sheesh this can be done using a few nimh aa cells and some cheap solar cells from a solar garden light, but firstly you need to know what your doing.
My solar garden lights operate all night long (8 hours) only after charging 16 hours in full sunshine in the middle of summer. In spring and in fall they light only a few hours. They use an ultra-bright red, green and blue LED that slowly fades and brightens its colours one at a time.
 

vbj4

New Member
here is the bulb i wanted to use
http://www.allelectronics.com/cgi-bin/item/LED-121/340500/ULTRA-BRIGHT_WHITE_LED,_5MM_.html

this is the panel
http://www.allelectronics.com/cgi-bin/item/SPL-6012/565/12V_SOLAR_PANEL__CHARGER_.html

the battery that i had planned on using didnt really cost me anything. its just an old car battery that i never took back in for the $3 core charge. I just wanted to see if I could get it working before i put to much money in to it.

so you guys think that panel won't do the job for me then? do you have any other suggestions i where I might find one for under $50?

Also, what should i look for when trying to by a panel. a higher amp rating or higher wattage?
 

audioguru

Well-Known Member
Most Helpful Member
That solar panel has even less current than the one I got from Canadian Tire for $9.99CAN which is $8.49US. I'll measure its output again today at noon, because it is very sunny.

Those white LEDs don't even have a brightness rating like all LEDs from other places.

An old car battery won't work. If it hasn't been kept charged then it is ruined and won't hold a charge.
 

vbj4

New Member
well i did get the battery to hold a charge. i do have some skills in battery reconditioning. it was my fiances dads truck. im trying to bring it back to life and figured a new battery for a truck that has been sitting for a few years wouldnt be such a bad idea. i took it up to the auto parts store to test it and they said it was ok. I understand the need to buy a real battery for my solar dreams in the future, but this should be good enough to get the ball rolling.

looking at canadian tire =)...
 

audioguru

Well-Known Member
Most Helpful Member
The solar panels aren't on sale at Canadian Tire anymore. They are $29.99CAN ordinary price now.
 

thekingkisna

New Member
solar panel question

hey my question on solar panel.. I have 2 solar panels and combining them in series gives me 4 volts. but then when i connect them to a LED.. LED doesnt glow.. when i connect the LED to a set of pencil batteries the LED does glow.. why is this anyone knows??
 

bananasiong

New Member
thekingkisna said:
hey my question on solar panel.. I have 2 solar panels and combining them in series gives me 4 volts. but then when i connect them to a LED.. LED doesnt glow.. when i connect the LED to a set of pencil batteries the LED does glow.. why is this anyone knows??
Current.

A few lemons in series give you 4 volts also, but it doesn't turn the LED on just because of current.

Have you noticed there is a small box at the electronics shop which is used to test LED's? There are a few rating of current.
 
Last edited:

Hero999

Banned
Perhapps the pannel doesn't output enough current to light the LED.

Lol this poll is funny "Am I a N00B?", yes you probably are!
 

thekingkisna

New Member
well.. how do u find how much current is required. do u have current ratings for the solar panels too.. the battery output voltage is 3.01 volts and the output voltage from the solar panels is abot 4.25 then why is LED is not lightin up??? any site that can answer me this question
 

Hero999

Banned
Please delete your replies in the other threads, (apart from being annoying) asking the same question over and over confuses people, it won't increase the chances of getting help.

Yes you do need the ratings for the solar pannels, if they're not generating enough current then the LED will be to dim for you to see.

What's the volt drop of the LED? Are you sure you're connecting it the right way round.

Also may I ask why? There's no point in connecting an LED to a solar pannel.
 

thekingkisna

New Member
i want a motor to run with the help of solar panels.. the walkman motor.. 2 volts one.. but then as a test had connected the led.. so unable to see it gettin the current..
 

Hero999

Banned
Get a more powerful solar cell then. This wasn't scavenged from an old calculator was it?

Did you test this in daylight or under tungston?

Where abouts in the world do you live?

Here in England, it's late autumn in the sun is quite week, it's getting colder and the leaves are falling. You won't get much power from any solar cell even at mid-day.
 

thekingkisna

New Member
me from country where whole of US loves to hate..I m from india. they were indeed scavanged from a new calculator.. CASIO one.. its also winter in india.. but then the solar cell had given enuf current that LED lighted up but it was very very dim.. and does it make a difference to put it under the tungsten rather than the tubelight
 

Hero999

Banned
That solar cell isn't powerful enough to powr the motor which will require 1000 times the current to even start moving as it does to very dimly light an LED.
 
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