solar powered lights as emegency light

**badkuk** · January 2nd, 2014 09:03 AM

Just thinking outside the box: the idea is to place a small solar powered LED light indoors; under normal conditions, you have the lights turned on, and the LED light gets charged. When there's a brownout, the LED light goes on.

Apparently indoor light isn't quite enough to power up the LED light...but the device i tested with had four LED bulbs. i'm thinking about getting one of those single LED bulb solar powered lawn lights, baka gumana coz there's only one bulb?

i know i can just get an emergency light and be done with it...pero as i said, just thinking a bit out of the box :0

**oj88** · January 2nd, 2014 10:17 AM

Conventionally, solar power is used to charge a storage device (battery, in our case) and the battery in turn is used to light up the LED. Is this what you're trying to achieve? Or are you trying to light up the LED straight from a solar panel using indoor lighting?

Domestic indoor lighting is nowhere nearly as bright as sunlight so it's not used for anything other than say, turning on calculators or charge wristwatches. These things requires only a few microamps to work. However, a typical LED (not the ones used as indicators, but rather, those white ones that are suitable for illumination) requires a minimum of 50 to 100mA or more. As an example, a 1W LED requires around 330mA*3V.

A commercially available 3V/270mA solar panel is about the size of a pack of cigarettes. Although, it is rated as such, this is so at ideal conditions (ie. facing right smack at the sun, at noon, and in clear weather). To be able to produce the same amount of power indoors would require a larger panel. But then, you'll run into cost-benefit and practical issues with such approach.

Now, let's go back to being clear on what you want to achieve.

**Walter** · January 2nd, 2014 10:24 AM

You can buy a solar panel light set for about 6T. Package includes solar panel, battery and 4 LED lights. They're available in Ongpin and Raon shops.

**ghosthunter** · January 2nd, 2014 10:27 AM

Originally Posted by badkuk

Just thinking outside the box: the idea is to place a small solar powered LED light indoors; under normal conditions, you have the lights turned on, and the LED light gets charged. When there's a brownout, the LED light goes on.

Apparently indoor light isn't quite enough to power up the LED light...but the device i tested with had four LED bulbs. i'm thinking about getting one of those single LED bulb solar powered lawn lights, baka gumana coz there's only one bulb?

i know i can just get an emergency light and be done with it...pero as i said, just thinking a bit out of the box :0

Solar garden lights is not bright enough to light up any area bigger than a square foot in area.

If you want emergency lighting for the whole room/house, why not check your circuit breaker's wiring and see if a particular breaker is wired to LIGHTS ONLY to particular rooms. If it's lights only, you can install a UPS on that room's lights power-line so you can have the normal room lights powered up even when the power goes out. Of course, this is only good for the an hour or two until the UPS battery runs out.

**badkuk** · January 2nd, 2014 10:40 AM

Originally Posted by oj88

Conventionally, solar power is used to charge a storage device (battery, in our case) and the battery in turn is used to light up the LED. Is this what you're trying to achieve? Or are you trying to light up the LED straight from a solar panel using indoor lighting?

Domestic indoor lighting is nowhere nearly as bright as sunlight so it's not used for anything other than say, turning on calculators or charge wristwatches. These things requires only a few microamps to work. However, a typical LED (not the ones used as indicators, but rather, those white ones that are suitable for illumination) requires a minimum of 50 to 100mA or more. As an example, a 1W LED requires around 330mA*3V.

A commercially available 3V/270mA solar panel is about the size of a pack of cigarettes. Although, it is rated as such, this is so at ideal conditions (ie. facing right smack at the sun, at noon, and in clear weather). To be able to produce the same amount of power indoors would require a larger panel. But then, you'll run into cost-benefit and practical issues with such approach.

Now, let's go back to being clear on what you want to achieve.

Basically i was thinking about using solar powered LED lights as emergency lights for the home. e.g. under normal conditions, we'd have the lights turned on at night -- i was hoping that indoor lighting would be enough to charge the solar powered lights -- then, when a blackout hits, the lights go out, and the solar powered LED lights kick in. Doesn't matter that it only lasts a few minutes, just enough for you to reach the nearby flashlight and/or get out of the house.

Thanks for the explanation sir, seems malabo nga tong mangyari

*sir gh: interesting suggestion sir, but i was hoping for something a little simpler

Nabad trip din kasi ako sa mga emergency lights. i forked up around 1.4k++ for a rebranded China-made LED emergency light, wala pang isang taon, sira na. Then i forked up another 1k++ for a local but reputable brand(at least yung ibang appliances nila), ganun din.

heck, i may just bite the bullet and buy the Philips unit at Ace

**oj88** · January 2nd, 2014 10:42 AM

^^Switching to LED lamps will prolong the backup power, but not as much. UPS's aren't very efficient. It requires a significant amount of parasitic power to keep the transistors in the inverter circuitry firing.

**oj88** · January 2nd, 2014 10:58 AM

Originally Posted by badkuk

---snip---

Nabad trip din kasi ako sa mga emergency lights. i forked up around 1.4k++ for a rebranded China-made LED emergency light, wala pang isang taon, sira na. Then i forked up another 1k++ for a local but reputable brand(at least yung ibang appliances nila), ganun din.

heck, i may just bite the bullet and buy the Philips unit at Ace

Usually, the only thing that breaks down in emergency lights are the batteries. These units are plugged-in 24/7 and the batteries are pretty much trickle-charged indefinitely. It is safe to assume that the batteries are relatively over-charged all the time so it stands to reason that the batteries will get used up or experience wear and tear whether or not the emergency light was used or not. Parang auto insurance or HMO... you pay for the premium whether or not you make a claim.

It's actually a necessity to check the condition of the batteries every month (ie. unplug it and see if it can provide lighting for at least 30 minutes) and replace the same when they've been degraded.

**badkuk** · January 2nd, 2014 12:33 PM

Originally Posted by oj88

Usually, the only thing that breaks down in emergency lights are the batteries. These units are plugged-in 24/7 and the batteries are pretty much trickle-charged indefinitely. It is safe to assume that the batteries are relatively over-charged all the time so it stands to reason that the batteries will get used up or experience wear and tear whether or not the emergency light was used or not. Parang auto insurance or HMO... you pay for the premium whether or not you make a claim.

It's actually a necessity to check the condition of the batteries every month (ie. unplug it and see if it can provide lighting for at least 30 minutes) and replace the same when they've been degraded.

Sorry forgot to mention: in both cases, OK naman yung battery:

China made unit - one of the lights wold "flicker" while charging. i get the feeling that something's shorted out inside
Locally made unit - replaced the battery, still wouldn't work. Baka nadale sa overcharging(although the unit's supposed to have overcharge protection)

**12vdc** · January 2nd, 2014 01:02 PM

^ The switching circuit is the problem, usually its semiconductor controlled or triac. Problem with commercial emergency lights is that you need to periodically check/replace the batteries, and that adds to your home maintenance routine. The old system use 6V VRLA batteries in 6V lightning, while newer LED emergency lights use 4V batteries that is not common in the grocery. As long as the emergency light is plugged, batteries tend to wear fast because most commercial charger are poorly designed, add to that VRLA wants cool environments for them to last.

If you are a DIYer, you can just buy a DPDT relay, it comes in AC powered that can be mounted in a rail. At normal condition when there is commercial power, relay is energized and the contacts going to the emergency lightning is disconneted. When commercial power turns off, relay contacts will go to normally-closed state activating the emergency light. You will be needing a used car battery or any VRLA rated atleast 40AH, 12V Led lights(common to automotive applications)-or a flourescent tube with cheap electronic ballast(similar to what autos and bus use). Charge the battery every month for about 4hours.

Going DIY has some bonus...
For prolonged blackouts, you may run a wire going to your car.
CDRKing automotive inverters can be wired too if you want to charge mobile phones.
Connect a 12V solar charging sytem..
Simple and endless possibilities.

BTW, I have this in the farm and house in the province, its running for 5+yrs batteries just wont die.

**ghosthunter** · January 2nd, 2014 03:08 PM

Originally Posted by badkuk

*sir gh: interesting suggestion sir, but i was hoping for something a little simpler

For those totally lazy from doing DIY .... there is the screw-in type emergency light.

FOR MORE INFO: AE Light EmergiBulb LED Emergency Light Bulb, 6000K, Clear Lens - KnifeCenter

I have seen local LED lighting companies selling similar products so this is already available in the local market. Just a matter of finding a store that has it.