Power Outage, How many Lumens, How many batteries? (for lights and more)

[subwoofer]

Re: Power Outage, How many Lumens, How many batteries?

May sound a bit flippant, but buy a bag of 100 tea lights and pack of disposable lighters. Total outlay <$10 and you have a good couple of weeks of romantic off-grid light.

It is amazing how little light you actually need if it gets really dark and it can be fun to see how we used to live

Though the above is actually quite serious, I think you are over thinking this. One unknown is how long the power will be off. A friend of mine lived in a remote village where they lost power for 8 weeks. The roads were cut off, so running a car engine to recharge batteries was limited by the lack of being able to drive to fill up with fuel. Weather was bad so solar was not much of an option. In the end the choice was limited to candles as a source of light.

Another option is to try it out for your required test period. Working in IT we say that an 'unverified backup is no backup at all', meaning that unless you actually try out your backup you won't know if it actually works. So pick a couple of weeks and switch off the mains power at the consumer unit and live your scenario. You can report back and tell us how many batteries you needed.

 

[Sub_Umbra]

Re: Power Outage, How many Lumens, How many batteries?

May sound a bit flippant, but buy a bag of 100 tea lights and pack of disposable lighters. Total outlay <$10 and you have a good couple of weeks of romantic off-grid light...

Emphasis mine.

I would advise people to avoid candles at all costs during an outage when the fire department may be stressed out or nonexistent... When our power is out after a storm I walk around to all of my closest neighbors and make sure that they have flashlights. If they don't I will lend them one (with batteries) so they won't have to burn candles next to MY house. I stock candles for trade goods but I wouldn't trade them to anyone who lives within a couple hundred feet of me...

A 9v Pak-Lite and two lithium batteries will provide 2,000 hours of runtime. Very few have put by enough fuel, food and water to take them through the runtime that a Pak-Lite and a spare battery will deliver.

To deliberately plan to use an open flame for light when there may be no fire department or even water to put out a fire would seem flippant, especially when there are so many affordable alternatives in the 21st century.

 

[Poppy]

Re: Power Outage, How many Lumens, How many batteries?

<snip> I think you are over thinking this. One unknown is how long the power will be off. A friend of mine lived in a remote village where they lost power for 8 weeks. The roads were cut off, so running a car engine to recharge batteries was limited by the lack of being able to drive to fill up with fuel. Weather was bad so solar was not much of an option. In the end the choice was limited to candles as a source of light.

I estimate that a single 18650 battery will supply 80-100 lumens for 7-10 hours, and 40 lumens for 40 hours.
Most here seem to feel comfortable sitting in a room lit @ 100 lumens (or less), so that is one 18650 a day, or less.

I estimate that my car burns 2-3 gallons of fuel per hour at 50-72 MPH ( I get 25 mpg)

I estimate that the average car alternator has a 940 watt hours/hour extra capacity, beyond what it takes to run the engine itself. That relates to 15.77 watt hours/ per minute.
I estimate that six 18650 batteries have a capacity of 70 watt hours.
Therefore the average alternator, can replace the energy, taken from the car battery to charge six 18650s, in about 5 minutes.

In other words the engine would have to run about a minute for each battery.
If we do the math, and extrapolate out, 7 X 8= 56 days times 1 battery / day= 56 batteries, and 56 minutes of engine running - burning between 2-3 gallons, and in my car that is 1/8 to 3/16ths of a tank.

In two months, I would hope that I was able to make a few trips to the grocery store, or HUNGER will be my bigger concern. While going for groceries, I would be recharging the car battery.

Another option is to try it out for your required test period.

No thanks... I'd rather do the math.

 

[subwoofer]

Re: Power Outage, How many Lumens, How many batteries?

deleted

 

[Etsu]

Re: Power Outage, How many Lumens, How many batteries?

To deliberately plan to use an open flame for light when there may be no fire department or even water to put out a fire would seem flippant, especially when there are so many affordable alternatives in the 21st century.

Fair point. Use a flashlight if it's available. But I think you're overstating the danger of candles. They've been used for thousands of years, and I don't think they were any more dangerous than the electrical stuff we use in our homes today. Keep a candle away from combustibles, preferably in one of those tea-light lanterns, and it will be fine. As with anything that gets hot (stove, oven, toaster, BBQ), don't leave it unattended (not a problem if you're using it for light).

If a neighbor approached me and asked me not to use candles, I might think that he's telling me I'm stupid.

 

[bluemax_1]

Re: Power Outage, How many Lumens, How many batteries?

Fair point. Use a flashlight if it's available. But I think you're overstating the danger of candles. They've been used for thousands of years, and I don't think they were any more dangerous than the electrical stuff we use in our homes today. Keep a candle away from combustibles, preferably in one of those tea-light lanterns, and it will be fine. As with anything that gets hot (stove, oven, toaster, BBQ), don't leave it unattended (not a problem if you're using it for light).

If a neighbor approached me and asked me not to use candles, I might think that he's telling me I'm stupid.

I think the problem these days is that very, very few people use candles aside from birthday cakes and romantic dinners.

I recall my parents using them during blackouts when I was a child, and some of the things they did make a lot of sense from an analytical point of view. For instance, they'd usually use those long white candles that you could get in a 6-pack and place these on a tuna can set in the middle of a light colored basin half filled with water.

An old trick their parents taught them, they said. The light colored basin and the water reflected more of the light upwards for a ceiling bounce and I realized if a candle fell over or was knocked over, it immediately went out when it fell in the water.

Although it only takes a little common sense to use candles safely, the lack of common usage these days means many folks may not think to take enough precautions. I've been to other friend's houses when their parents brought out candles during a blackout who would place them in places where they obviously didn't consider the risk especially if there are animals and small children in the house.

With sufficient precautions and common sense, yes, tea lights could be a cheap alternative, but as Sub Umbra mentioned, when the fire department may be overburdened or non functioning, why take the risk when there are so many reasonably priced options for long running electric lighting these days?

Back in the day when using candles in blackouts was much more common, any extended blackout usually resulted in news reports of home fires begun by careless usage of candles.


Max

 

[filibuster]

Re: Power Outage, How many Lumens, How many batteries?

Fair point. Use a flashlight if it's available. But I think you're overstating the danger of candles. They've been used for thousands of years, and I don't think they were any more dangerous than the electrical stuff we use in our homes today. Keep a candle away from combustibles, preferably in one of those tea-light lanterns, and it will be fine. As with anything that gets hot (stove, oven, toaster, BBQ), don't leave it unattended (not a problem if you're using it for light).

With small children around a candle would be a liability to have burning inside and something that I wouldn't want them to use by themselves unattended.

The brightest candle light output is on par to even the the dimmest LED lantern. Shown on the light output comparison page are a couple of "bright" candles for reference, with the "100 hour candle" giving off the most light. Even so, at $5-$6 each for a "100 hour candle" I could buy six D cell alkaline batteries which would give me over 100 hours of high mode light (much much brighter than a candles light) using a Rayovac 3D lantern or close to 200 hours if I run the lantern on low, which is still much brighter than a candle.

Sure I have to buy the lantern too but in doing so I get a safe and very usable light source with no fumes, fire danger or the need for matches to start my light source. Plus any child can take the lantern and easily use it as needed to study, work or whatever without my supervision. In an emergency I'll likely have many more pressing concerns and having to worry about the kids burning down the house won't be one of them ;-)

 

[mesa232323]

Re: Power Outage, How many Lumens, How many batteries?

L3 ILLUMINATIONS L10 quantity: 3
AA Eneloop quantity: 4

Moonlight mode lasts for days nonstop. In a 5 day period, I may never need to recharge.

 

[Redhat703]

Re: Power Outage, How many Lumens, How many batteries?

Power was out last night for about 3 hrs. I used 2 LED lanterns both in medium mode in kitchen and dining room. The MD3 with M91W was put in tail-stand low mode in bedroom gave out enough light.
I use mostly li-ion for my lights. For backup, AA lithium and alkaline, D size alkaline, CR123.

 

[Poppy]

Re: Power Outage, How many Lumens, How many batteries?

- The family will most likely be together in the family or dining room since there are no electronic toys to distract individuals; a ceiling-bounced ~100 lumens is plenty for this setting, our family has dined and played board games under this very scenario during a few Earth Hours.

<snip>
- The biggest drain on batteries isn't lights at all; you're going to want a source of news and information on at all times, or at least a morale boost when news isn't on - your battery-powered radio will be on nonstop for roughly 16 hours a day regardless of all other conditions, and at that rate most digital radios will need a battery swap every other day.

I just tested two different radios that I have.
One, is one of those little 2x4 inch transistor radios. It takes 3 AAs and draws 17 milliamps at 4.5 volts. or 0.0765 watts
The other, is a small boom-box, it has two 3 inch speakers, it runs on 8 C cell batteries and draws 80 milliamps, at 12 volts. or 0.96 watts.

In other words, the larger radio draws 12.5 times as much current as the smaller radio.

If my math is correct,
The smaller radio may run for 100 hours on three eneloops,
The larger radio only 25 hours on eight eneloops.

I offer this as a comparison, so that you might take this into consideration

 

[StarHalo]

Re: Power Outage, How many Lumens, How many batteries?

The larger radio only 25 hours on eight eneloops.

Yeah, boomboxes are a bad idea for emergency radio use; some of the smaller, more efficient options out there will give you over 200 hours on a pair of larger cells, a welcome reprieve when you're days into a power outage and you've never had to consider changing batteries for your radio..

 

[LightWalker]

Re: Power Outage, How many Lumens, How many batteries?

A boombox would be about as efficient if you plug in some headphones/earbuds.

 

[Spin]

Re: Power Outage, How many Lumens, How many batteries?

You can also use earbuds on the smaller radio to increase battery longevity.....Boombox a very poor emergency radio.

 

[Sub_Umbra]

Re: Power Outage, How many Lumens, How many batteries?

One of the problems with ear buds in an emergency is that only one person may listen at a time. I greatly prefer even something like a $13-15 Sony IFC-F10 with a speaker and 200 hour runtime over anything with ear buds for nearly all grid down situations.

Anyone contemplating an emergency radio would be well served by reading the "Small Portable Radio's?" thread.

 

[davyro]

Re: Power Outage, How many Lumens, How many batteries?

i'd have a box of 24 surefire cr123a primaries & all 4 of us would have an hds light each,of course they'd all be on a very low lumen setting to save energy & basically we wouldn't need seering brightness to light up our rooms as our night time vision would be very sensitive & used to the dark,i'd also have my little 2xaa sony radio which batteries last for at least 6 weeks when its in use for 8hrs a day

 

[creyc]

Re: Power Outage, How many Lumens, How many batteries?

We had almost a full days power outage not too long ago, and I can fairly confidently say I would definitely NOT make it through a week long outage.

Between the 4 of us living at the house we went through (6) 18650s, (3-4) 18350s and (4) AA Eneloops in about 24 hours. I've since decided I should start stockpiling many many more cells than I currently own, and to buy a generator. I was pretty surprised by how ill-prepared we all were, just for a single day.

The Pak-Lite suggestion is a good one, and I think I will order up a few. I assume the Pak-Lite Super is the way to go, with its 600-hour low mode?

 

[Poppy]

Re: Power Outage, How many Lumens, How many batteries?

creyc,
I am guessing that if you went through that many batteries in 24 hours, that you, and your family members like a good amount of light.
I don't think that pac-lights throw a lot of light, but rather throw a small amount of light for a long time. I'g guessing, like a single candle. You might look at the comparisons in the link posted above for lanterns. Considering the amount of light that you used, I don't think that you'd be overly happy with the small amount of output of pak-lights.

If you bought a couple of spare 18650s and had a car charger for the lot, you'd be good to go, even if the outage lasted a week.

Do you know how many lumens each of your lights put out?
I'm curious to know how many lumens you felt that you needed to be comfortable.
Did you light one room or a multiple of rooms?

 

[creyc]

Re: Power Outage, How many Lumens, How many batteries?

creyc,
I am guessing that if you went through that many batteries in 24 hours, that you, and your family members like a good amount of light.
I don't think that pac-lights throw a lot of light, but rather throw a small amount of light for a long time. I'g guessing, like a single candle. You might look at the comparisons in the link posted above for lanterns. Considering the amount of light that you used, I don't think that you'd be overly happy with the small amount of output of pak-lights.

If you bought a couple of spare 18650s and had a car charger for the lot, you'd be good to go, even if the outage lasted a week.

Do you know how many lumens each of your lights put out?
I'm curious to know how many lumens you felt that you needed to be comfortable.
Did you light one room or a multiple of rooms?

Poppy,

Yes we did illuminate the house quite brightly. Truth be told I wasn't too concerned with trying to conserve power and if I thought about it I definitely could have cut back on most of the lights. The outage was very localized, and I had friends and family with power nearby so it was more a camping feeling than a survival experience.

That said, the primary battery consumer was the Blackshadow Terminator, set on medium and left to illuminate a very large room via ceiling bounce. Rated output for this mode is around 1500 lm, I believe. The room was quite well illuminated and everyone seemed happy with it. I would have dropped down to low if the PWM wasn't as noticeable, but I am very sensitive to flickering. On (4) 18650s this light lasts right around 2 hours on medium.

During most of the chores I had a Zebralight H502w strapped to my head, which ate about half of those AAs. I also carried a Thrunite Ti but didn't use it a whole lot. Additionally we passed around a Jetbeam RRT-01 on 18350s, usually turned up fairly bright, a ShiningBeam S-Mini and an EagleTac D25A for personal use. Lastly a Surefire 6P with triple Nichia 219 mule was used for flooding the kitchen and then bedroom.

Most of the time we had multiple lights on in multiple rooms, which is probably why we devoured so many lumens that day. Personally I felt like 100-200 lumens well bounced off the ceiling was plenty for my own comfort and well being.

 

[RedLED]

Re: Power Outage, How many Lumens, How many batteries?

A couple of years ago, Southern California, and a huge part of the southwest US want dark, I think it was September 2011?

I went to the back of the house, and said 'what the hell is that bright beam on the wall'. It was coming from a white PAL light I put on top of a cabinet and forgot about. However, in that darkness it was very bright.

 

[N8N]

Re: Power Outage, How many Lumens, How many batteries?

Things are obviously different now than when I was a kid, but I think I would still go with the plan that we used back then, have kerosene lanterns stashed around the house in most rooms where people are likely to congregate. then you only have flashlights on each person for walking around, using the facilities in the middle of the night, etc. Obviously flashlights are cheaper to run today than they were back in the day but kerosene lantern is still more practical, unless you have a generator. Fill them with "lamp oil" if you don't like that kerosene smell, then refill with kero if the outage lasts so long that they run dry.