Reccomend Most efficient CFL for power outage

DaMeatMan

Newly Enlightened
Joined
Sep 25, 2003
Messages
197
Location
Toronto, Ontario, Canada
Hey guy's,

I'm looking for a reccomendation on the most energy efficient CFL bulb for use in emergency power outages with a UPS battery backup system.

Requirements:

- 3W - 10 W
- 300 - 600 Lumens
- Warm white is preffered

Essentially, what is the brightest CFL bulb that i can buy with the lowest possible power consumption?

I'm also looking at one of the Coleman dual or quad cree lantern for use with my portable AC/DC power pack for extended run time. But i would really like to be able to get some nice conventional warm white lighting with the CFL to feel more "at home" during a power outage without sucking the UPS dry too quickly.
 
Why don't you just build yourself a multi output LED light "panel" (think, a bunch of LED's, w/optics,reflectors on a large heatsink, waterproofed). With that amount of power, you can get a lot more light than with CFL, or, on the same output, and powerpack, longer runtime. Warm white LED's are still about as efficient as warm white CFL bulbs.

Heck, you could do one brighter one, for larger areas, and one or two smaller ones, for work lights, in other areas.
 
That's great advice from John. While you're at it, why don't you also install solar panels on your roof and have them connected to a battery bank in your basement to collect any excess energy you aren't using. Then when there's an emergency, you can just power your house with it.
 
Those are both great suggestions that i am thinking of tackling for a longer term project. But for the more immediate future i want to be ready to light things up in a pinch using what i already have on hand should power go out again.

I started thinking of this because i recently found myself cought with my pants down last week when we got hit with a freak Tornado just outside of Toronto, Ontario, Canada where i live. I live on the 32nd floor of an older apartment so my "emergency plan" was always kind of based on living at home with my folks, not in a high rise apartment. Let me tell you it was not fun carrying 10 Litre jug's of water, propane stove, canned food etc up 32 flights of stairs that are not ventilated without power! To make matters worse, our hallway and stairwell emergency lighting only lasted for the first night, after that we were left with pitch black halls and stairwells!

Living in an apartment I really can't implement any more then 1 or 2 small panels outside on the balcony. Actually ebay has some excellent deals on pre-tabbed solar cells from Evergreen solar that i was thinking of purchasing to get my feet wet with solar down the road.

While on lunch at work today i drove down to Walmart and found some warm white EnerSaver CFL bulbs with standard sized screw in base. It is rated at 450 Lumens at 7W which seems to be the most efficient bulbs that i can find locally, and the kicker was that i was charged only $1.00 each! I recall seeing a price tag of just over 5 bucks while looking at them on the shelf, so maybe they are on special or they just got scanned in incorrectly.

I also found some AC powered LED accent lights that were rated at only 2 watts, these were from Lights of America and are capable of being strung together in series for under the cabinet accent lighting.

Anyway i'll try these out tonight and see what kind of light they put out. In the meantime any other suggestions would be welcome.

By the way, what do your power outage kit's look like?
 
CFLs are fine energy savers... when line operated. Though LEDs may be even more efficient, reliable AND efficient 120V LED bulbs are usually expensive. I would NOT count on a lot CFLs for backup lighting on small solar, small generators, and/or cheap inverters. Many cheap CFLs have a very low power factor.

One might expect 60W of CFLs to only draw 1/2A at 120V. But due to the reactive load (Power Factor) they would commonly draw 1.0 Amps. (PF =.5) This reduces apparent efficiency of the CFLs by half, on a battery powered inverter. One must size oversize all power sources to account for this. I have never been happy with small (<500W) inverter reliability, and CFLs on stepped sine inverters aggravate reliability problems, IMHO.

I have some CFLs in daily use that I might run on my generator(s) but they are a tiny fraction of my overall power outage load. For 12V backup power, I like 3 white LEDS in series, with a (preferably switching, if the LEDs are high power) current regulator. More efficient, and no surprises. I have a couple of halogen incan's (5W 12V, and 10W 12 V) just because the spectrum lifts the mood in gloomy times.

Plus I own 3 flashlights... per person in the neighborhood. ;-)
 
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Assuming you don't or don't plan to own a generator, power is usually saved by charging up batteries, and batteries are DC creatures, CFLs are AC creatures, to power CFLs usually require an AC inverter that will convert DC to AC. UPSes will work but usually batteries are tiny compared to the inverters and the circuitry's designed for short period loads and not as dedicated backup supplies, as a result some key components simply lack sufficient heatsinking.

Inverter has losses, and it also makes problems for electronics.
Most budget inverters are modified sine, meaning their output is give or take in square waves. This gives CFL ballasts a delightful [or annoying] hum while in operation, increases heat output, decreasing efficiency.

If you chose a pure sine UPS, then good for you, they are server grade UPSes and if you can afford those you can certainly go for LEDs :D

Personally, its much more efficient to run DC appliances from batteries. For one thing, the power is clean, not as rippling as buddy, fido, or spot paddling in the bathtub.

LEDs are DC creatures, add AC and they protest like firecrackers. LEDs can be stringed in series, CFLs cannot. LEDs are safe, CFL's are hazardous. Drop the two at the same height and you'll see what I mean. Use an appropriately sized heatsink and an appropriately sized driver LEDs will love you till the end of time. AC LED drivers are more expensive as DC LED drivers, they should be...because there's more complications with AC than there is with DC.

When there's line power we tend to waste power, why? because its convenient. you can light up the living room, the computer desk, the kitchen and even your cigar at the same time without thinking twice about it. When the power goes out, then you wonder why its so dark everywhere. Put your lighting needs into perspective, ask yourself "Do I really need all this light?" or "If I need to be productive, what places do I need light the most?" Better yet, ask yourself this "In case of an emergency, what exits do I need to have lighted?"

Once you have that down, then you can nit and pick on what best suits your needs. :)

CFLs for Long term? well, it depends on your budget. I'm fortunate to implement a few 12V LED strings around the house with a transfer box that connects them to a 12V battery when line power quits. Its plans are set, just not built yet. "why?" because I'm lazy:whistle:

good thinking on the UPS, I once wanted to do the same as well, until I plugged my UPS into itself in the dark. :shakehead
 
[good thread]

While CFLs are by themselves very efficient in terms of energy / lumens, the built in ballasts used are another problem.

You go from Line AC 120 volts > charging circuit in UPS > Gel battery > inverter + psuedo 120 volts > ballast in CFL (300 volts?). Yeah....pretty inefficient.

Still a better solution though than an Incan given that a 7watt CFL puts out a substantial amount of light with a pretty regulated power source.

All things considered, solar or otherwise, you still need a way to store power, and that means batteries (unless you just happen to be a rep for a carbon gel capacitor company). Batteries require charging circuits, and that's what UPSs are fairly good at.

So, why not keep your current UPS, but just wire the terminals up for 12 volts out to a BuckPuck or something, and six Crees to get your color and lumen requirement? Power goes out - UPS trips - flip a toggle and away you go. Screw the inverter all together.
 
You guy's are absolutely right.. i think having been cought with my pants down during that last outage i was left scrambling for an immediate solution that required zero modding.. i.e.. i was lazy.

These are all good suggestions and i've decided i'm going to get to work on the following this weekend:

- Provide Cig light output for UPS with direct connection to the UPS 12 volt battery. This will be used to power directly some battery based LED light sources i already have laying around. Can also be used to connect a solar panel for charging.. of course i would use a relatively in-expensive solar charge controller to monitor and maintain the battery.

- Going to design some emergency LED based lighting that can be used as a semi-permanent lighting fixture. It will Likely be Cree based with a buck boost converter for utility to ensure it can always be powered regardless of available battery source.. or perhaps just a buck circuit for simplicity.. we will see. It will have to look pretty if my Fiance is going to accept them, so i'll likely use the housing from an existing production ready device. I was thinking of using these as the host. http://www.lightsofamerica.com/en/Products/7200-LED-BN.aspx

I've heard allot of bad reviews for anything coming from Lights of America including the above device. The device above seems to be in series and is using cheap LED's that seem to fail over time, the result is the whole fixture goes out. It does diffuse the light pretty well and looks relatively attractive and unobtrusive, so perhaps that will be my host of choice. On a side note, one of these will sufficiently light up a room as is. It provides enough light to comfortably see what ur doing, 2 will provide a very comfortable amount of light to go about your daily business without feeling like your living in a cave.

I think that pretty well covers me. Any suggestions on a pariticular converter board for the light fixtures? I have been away from CPF for a while, so i'm not up to date on the latest offerings from our members.
 
My experience with CFL lighting is a bit different. I've run my outdoor lighting (two CFL 9W bulbs) from a MSW inverter for about 2 years. Initially I ran them for 6 hours a night, now dusk to dawn. Zero issues.

Now I run two 20W CFL bulbs from another MSW inverter in my living room each night. No flicker, no hum, no issues.

http://2manytoyz.com/cflinverter.html

http://2manytoyz.com/gridless.html

As for efficiency: "I then measured the DC current to determine the current draw while running from the inverter. 3.40 Amps. 3.4 A x 12 V = 40.8 Watts. The inverter has some losses as well, but that's pretty close to the expected 40 Watts."

The reason I prefer CFL bulbs over LEDs is LEDs are directional. Great for task lighting, poor for general lighting.

But I am putting emergency lighting in both of our bathrooms this weekend, using 18 LED dome light fixtures by Pacer. Found them at Northern Tool locally, on sale for $14.99 each.

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I will be placing one of these in each bathroom, above the existing light fixtures. They will be completely hidden. I have a relay plugged into the grid that drops out when the grid goes down, and will turn on CFL lighting hidden in the kitchen's dropped ceiling, and also LED lighting in the bathrooms.

Obviously not as bright as the four existing CFL bulbs in the light fixture, but plenty bright enough to take care of business and shower. Nice part is this LED array only draws about 80mA, has built in current limiting resistors on the board, and is ready to be connected to something as simple as a SLA 7A 12V battery. This only draws less than 2 Amps per day (per module).

I have a 900AH battery bank and 615W of solar panels on the roof so far. I'm slowly taking all the rooms off the grid, but the emergency LED lighting will do for now. Simple project, might be a good choice for the OP.
 
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