LED Lighting System

[JamesJackson]

I know that there are a lot of knowledgeable folks on this forum, so what I have done may not rank very high.

Right now, my solar panel is charging my battery at home. I have put together a small lighting system that works very well. The solar panel is only 21 watts, and the sealed lead acid battery is a 17Ah capacity. I have a battery charge-regulator hooked up so that I do not over-charge the battery.

The fun part is that I am using high-power LEDs to illuminate my living/dining area. They are 5-watts each, and I am using 3 of them for a total of 15-watts.

I turn on the lights in the evening, and enjoy 4 hours of light before I go to bed. In the mornings, I use another hour while I get ready for work in the dark pre-dawn hours.

I have a LVD (Low Voltage Disconnect) circuit hooked in, but it has not kicked in as the battery rarely goes below 12.3 volts before it gets recharged. This circuit, as well as other added features, I've added to a printed circuit board that I've designed.

I am already thinking of ways to expand on this system - adding remote LED lights in the bathroom, or an amber porch light. These would only get used for another hour or so each day - but the battery can take it, since it has plenty of juice to spare.

It was really neat a few weeks ago when we had a thunderstorm pass through. The power went off. I went and turned on my LED lights, and we had enough light to see and get ready for work. I went outside to see how much of the area was affected. The entire mobile home park was dark, as well as the housing development behind us. The only lights on were the ones that I could see through the blinds on my home. I grinned and went back inside.

My electric bill has decreased a slight amount, too. Not too much, only a couple of dollars, but even that small amount helps.

My small system is great for the average person who is not wanting to invest thousands of dollars in solar panels and batteries to 'play' with off-grid power. All told, I believe that I have spent less than a thousand dollars. (That over the course of a few years.)

Regards,

James Jackson

Oztronics

[chadking]

Sounds like you're on the right track. That sounds similar to something I'm looking to set up in a little cabin over the hill. LED's are really an amazing step up from traditional lighting in power consumption, etc.

Keep on trucking with your system, and keep us informed when you make any additions!

[ghurd]

"what I have done may not rank very high"

You tried it.  That counts.  A lot.  You did it, and that helps some too.

The LEDs.  Are they series or parallel?  A huge and confusing issue, but series is better.

The "12.3V... LVD has not kicked... over the course of a few years..." (I took major liberties with the quote concept) means you have more power available.

So use it!

Like 25 GOOD yellow 5mm LEDs in a decent design uses a watt.  Dang nice porch light.  If your house is not blue.

Like 3 GOOD white LEDs in the bathroom use 20% of a watt. Not enough to shave, but plenty to tell if the seat is up or down, and on all night won't hurt a thing.

Like 24 LEDs or 1.5W of GOOD 5mm white LEDs is plenty to save with... or so I hear, because I don't often shave.  

GOOD and LED is not related by cost (much).

I love any story with neighbors in the dark!

Good job,

G-

[Ungrounded Lightning Rod]

...  The solar panel is only 21 watts, and the sealed lead acid battery is a 17Ah capacity.

The fun part is that I am using high-power LEDs to illuminate my living/dining area. They are 5-watts each, and I am using 3 of them for a total of 15-watts.

I turn on the lights in the evening, and enjoy 4 hours of light before I go to bed. In the mornings, I use another hour while I get ready for work in the dark pre-dawn hours.

15. W * 5 HR/day = 75 Watthours/day usage.
    
17. AH * approx 12 V = approx 204 Watthours storage.
    
    

With your current lamp usage you're consuming about 36% of your

storage in one day, 72% in two.

 - You shouldn't EVER go past 80%.  So you only have storage for one dark day.

 - And it's better to stay in the 20% discharge range for a daily cycle - you're

   nearly twice that.

So you probably ought to double up on your battery to avoid premature failure.

21 watts * about 80% (because standard ratings are high for charging applications) * 5 solar hours/day = about 84 Watthours recharge/day.

You're using nearly all your available generation now.  That's fine while you're keeping ahead.  But get behind and it takes a long time to recover.  Add even a little more load and you'll systematically start spending more than you earn.  So you probably ought to double up on your solar panel, too.

Double both and your current setup will have storage to handle three utterly-dark days, only cycle the batteries down to 82% charge during sunny weaher, and recover from a day of total darkness or doubled usage in a single day of full sun.  At that point you can relax, and even add a little more load with confidence.

[watermanhfl]

James,

Great to hear you have working lights.  I use 4 lawn mover headlights wiring in series from my 48 volt, 10' turbine.

What I would like to know is some of the details of your adventure.  What did you use for a light switch and socket for the lights?

Tks Ant

[JamesJackson]

"The LEDs.  Are they series or parallel? "

The LEDs are in parallel. They are 12-volt units that I purchased.

Regards,

James Jackson

Oztronics

[JamesJackson]

Ahhh yes... all of the facts and figures and calculations.

Well, while I haven't written any data down, I can tell you that I have used this system for over a month now, and haven't dropped the battery any lower than 11.9 (or 11. volts. This was after two weeks of rain and overcast skies that I thought would never end. wide grin

During the day, the solar panel (Uni-Solar - not made anymore), would get just enough light through the clouds to recharge the battery just enough for that evenings' 4 hours of lighting.

I have a DVM permanently attached to the battery, and am closely watching the voltage - just because I am (or was) worried that I might drop the battery too low.

I feel that my current setup - a 21-watt solar panel, and a 17Ah battery are a good fit for what I have, and could probably accomodate another hour of load from a porch LED, or bathroom LED.

Thanks for your input, though.

Regards,

James Jackson

Oztronics

[JamesJackson]

"What did you use for a light switch and socket for the lights?"

This is what has taken me the longest to figure out. (I think a lot before I take action.)

What I did was discover a track lighting system at a local hardware store that came with three 20-watt halogen bulbs. It uses adhesive backing so that it can be applied to the wall. (I don't use the halogens - they sit in a box.)

The sockets are MR-16 - which means that the LEDs I am using have to plug right in to these - which they do.

It's all pretty much a 'plug-n-play' type system - using parts that one can pretty much buy and put together.

The 'switch' is pretty awesome. Again, I took some time thinking about this one. By nature, I'm lazy. I don't like to get up and walk over to a physical switch and flip on the lights. At first, I was going to use an RF switch, then I decided on using an InfraRed switch, as I already have remotes laying around for the TV, DVD and VCR that I could use. It works pretty cool, too. I can 'hit' the sensor from about 30 feet away and do not need to walk into a darkened room feeling for a switch to turn on the lights.

wide grin

Thanks for the questions.

Regards,

James Jackson

Oztronics

[Norm]

 Speaking of being able to tell if the toilet

seat is up or down remember the clear plastic

blue LED lit toilet seat....mighty purty !

                  ( :>) Norm.