Is there a simple device to give me 30 min of power?

Is there a simple device to make or buy to give me 30 min of power?

All I need is time to make a call to our electric company to let them know the power is out.

We have a signal booster that gives us cell phone coverage which needs power.

I am tired of buying a device that costs $500.00 to do that. Then the next time we need it no longer works.

Hi Anne,

If your vehicle / automobile is available during the power outage, then you have a portable 12 volt DC generator (vehicle running at idle) right there. In order to have AC power, a small 12 volt DC to 120 volt AC Inverter (i.e. from Radio Shack) can be hooked up to the vehicle's battery, or plugged it into the vehicle's cigarette lighter socket, or DC ass'y jack, which will easily power a phone, or cellphone booster.

When the power fails here, I use my computer's "extended backup time" UPS system to run 120 VAC powered items. The UPS uses a pair of sealed 35 ampere "outboard" batteries. During a power outage it will run a desktop computer for 30+ minutes along with my phone system.

The signal booster is in my laundry room which the only access has a large water tank and our well pressure tank so there is no room to get a vehicle in the area.

Put a battery on a trickle charger?  

How much power do you require? That's the starting point.

If your cell booster uses a "wall wart" transformer, the specifications you need will be on that. Otherwise, it will be on a sticker on the unit itself.

The signal booster is in my laundry room

Is the signal booster AC powered, and if so, is its power consumption less than 120 watts?  

Goal Zero's Yeti 200X delivers 187 Watt-Hours, so it could power such a device for an hour and a half, or could simultaneously recharge a couple cell phones or laptops, etc.

Basic unit would cost $300.  It would need to be recharged every 3-6 months, or simply kept plugged in, or charged via solar or a vehicle.

An extra $40 would enable it to be recharged from a vehicle for travel/camping use.

An extra $107 would enable (very very slow) solar recharging options  using a Nomad10 panel ($100) and a USB to USB-C cable ($7).  Faster, more expensive solar charging exists.

*Full disclosure, I have invested in Goal Zero's parent company, NRG Energy, precisely because I think these products are pretty cool.

Hi Anne;
If you use a small inverter on the car.
The A/C output is a  regular extension cord.
I suspect your phone uses minimal power so a 100' cord  or maybe? even more could be used.

If the power consumption is relatively low (as I suspect), an uninterruptible power supply (UPS) for office equipment may be an effective solution. Nothing with a battery lasts forever, though. If you're looking for longevity, lithium ion is the way to go.

If my thinking is correct here, Anne, you may just need to buy a UPS/APC box at any computer or electronics retailer.  It's basically a box with a battery inside that has outlets on the outside of the box.  Plug the UPS box into your power outlet on the wall and it keeps the battery inside charged.  Now plug your cell-phone booster into that box.   Just set it up this way and forget it!  This is how I have mine configured.  When the power goes out, the battery in the box will keep your cell phone booster running for a certain amount of time....I'm thinking easily for 30 min. and probably more if that is the only device plugged into the UPS box.  I just read that most boosters draw 15 - 20W typically which should be fine for most UPS boxes, but check if/when you purchase one with someone in the store who's knowledgeable on such issues.  (Actually, now that I'm thinking about it, I need to get one of these for my laptop/internet modem configuration since I've been making more phone calls from the computer over wifi instead of my phone.)

Good luck!

Darn you, Douglas, you beat me to it! :-)

Your requirement is to be able to get a message to your utility provider in case of a power interruption?

How often does this happen?

You say you have a signal booster for mobiles. Presumably that is connecting to a reasonably close mobile mast?

Personally I would consider whether you need it at all, especially at that price and with the reliability issues. Can you just jump in the car and head 10 minutes down the road to where you will have mobile signal?

Anne Miller wrote:The signal booster is in my laundry room which the only access has a large water tank and our well pressure tank so there is no room to get a vehicle in the area.

It is entirely okay to use any convenient length of common electrical extension cord, either plugged into the 12 VDC to 120 VAC Inverter Unit's output, or a computer system UPS's 120 VAC outlet, in order to get that emergency power 120 VAC source to where it is needed, i.e. your laundry room:o)

Cell boosters are expensive items. I would use a pure sine wave inverter if I went with the car-and-extension-cord route.

Edit: I see the inverter Thomas posted is a pure sine wave unit. Good.

John Weiland wrote:Darn you, Douglas, you beat me to it!

Actually Byron beat us both to it.

Okay, lets assume the cell booster is like mine, and draws about 20Watts. So you need 10Wh of storage. I would suggest you buy an inverter that runs on 12v as described above, and then if you really want to be cheap get some AA NiMH batteries. You will need 10x of these:

https://www.amazon.com/AmazonBasics-High-Capacity-Rechargeable-Batteries-Pre-charged/dp/B00HZV9WTM/ref=sr_1_5?crid=2HVBB2CHGUMLQ&keywords=aa+rechargeable+batteries&qid=1643576157&sprefix=AA+rechar%2Caps%2C715&sr=8-5

Tape them together in series and you will have a 12v 2.4Ah battery. Put your battery log on board, and nail it in place on both ends. Put your alligator clips on the nails, and you are in business. You will have 28.8 Wh available, which should give you almost an hour on fully charged cells, with a little to spare for the inverter draw.

Hi Anne,

I don’t know if you have any cordless tools, but I have a simple USB adapter that fits on one of my 18 volt tool batteries.  It can recharge my phone throughout the day.

This is a solution for tomorrow.  Do you need a something sooner?

Eric

We have a setup at our cabin where we have solar panels that charge a motorcycle battery. Then we connect from the charge controller to our signal booster (Weboost). We had to buy a special cable or connector, can't remember at the moment, but if you list the model of your signal booster, I might be able to let you know how you could run off a 12v battery. We are able to charge cell phones and run a few lights off the battery. At some point we'll probably get better panels, but we are just using ones from Harbor freight now.

It's worth checking the manual. There are a cell phone boosters designed for mobile use. They are run directly off the electrical system of a vehicle.

Anne,

I use this little device to charge my phone when I am not near an outlet.  It will happily charge my phone all day.

I checked online and I found a cheap Ryobi version that will do the same for about $75 with the battery, wall charger and USB adapter included.  But if you already have a cordless tool set, by all means use that platform.

Eric

Eric Hanson wrote:Hi Anne,

I don’t know if you have any cordless tools, but I have a simple USB adapter that fits on one of my 18 volt tool batteries.  It can recharge my phone throughout the day.

This is a solution for tomorrow.  Do you need a something sooner?

Eric

THANK YOU! That's my husband's birthday gift right there. We have Makita cordless drills and I just checked, they have one of these-plus an adapter to charge the batteries in your car while you drive. I never would have thought of those. He's going to love it.

Anne, it seems that you were able to access the internet yesterday. Does your power company have an e-mail address? That might work next time your power goes out.

I want to thank everyone who has responded to this thread.

I have learned a lot more about electricity and electronics just ready the thread and have realized that this signal booster is a fairly complicated piece of equipment.

It appears to use what we think of as 220V. The manual says 100 - 240V AC.

What we ended up doing is to buy 2 batteries for the backup system or whatever it is called.  We are hoping this will solve the problem that this device is having.

We will see when the batteries arrive.

I took DC Electronic in college so a know a little about the working of electronic devices.

It is my hope that since threads are perennial that this thread will be used by others to solve some of their problems or will help them find solutions to or for their needs.

Again, thank you everyone.

Anne,

I am really curious to see what your solution to this problem ultimately is.  My thought is that you need an inverter to convert 12v (I am assuming that your batteries are 12v batteries) to 220v.  You said that you have 2 batteries on the way.  Do you know how you are going to up that voltage yet?

Eric

It appears to use what we think of as 220V. The manual says 100 - 240V AC.  

I am picturing an electrician seeing your 20 Watt wall-wart plugged into a big 220v split-phase drier outlet, and keeling over on the spot! The reason the input voltage covers a really wide range is so that it can work on US 120v or European 220v  single phase. If you look on an ordinary laptop power supply, you will likely see it has the same input range (if you can read the tiny print). It means they can make just one power supply that works worldwide, and just swap out the end of the cord that plugs into the wall.

The booster itself probably runs on DC, mine is 5 volts and 4 amps. If it just has a regular household outlet plug, then you are stuck with supplying it with 120v AC (or somehow feeding it 220- it wont really care). If it has a wall adapter like mine, you could get a matching barrel connector and wire it directly to a battery that supplies the right voltage and current, which would be more efficient, but it would also be a little more involved.

Eric Hanson wrote:Anne, I am really curious to see what your solution to this problem ultimately is.  My thought is that you need an inverter to convert 12v (I am assuming that your batteries are 12v batteries) to 220v.  You said that you have 2 batteries on the way.  Do you know how you are going to up that voltage yet?  Eric

Earlier, I wrote a whole post answering your question.  Then I went to another window, promptly forgot I hadn't posted a reply.

Then the window got closed out. ...

The batteries we are buying are the same batteries that are used for our deer feeders so if this does not solve the problem we can still use the batteries in the deer feeders.

When we tested the batteries the test showed one battery was dead and one was still good.

The signal booster shows Power Supply: Input AC 100-240 V, 50-60 Hz, Output DC 12 V/3 A.


Thank you for starting this Building-battery-generator as this is something like what I was thinking about.

Do you feel this battery generator is powerful enough to give the signal booster at least 30 min of power?

Anne Miller wrote:
The signal booster shows Power Supply: Input AC 100-240 V, 50-60 Hz, Output DC 12 V/3 A.

...

Do you feel this battery generator is powerful enough to give the signal booster at least 30 min of power?

Hmmm...

12V direct current * 3amps = 36watts.  30 minutes of use would mean an 18 Amp-hour battery may be sufficient if directly connected to the device, with no inverter required.  

A direct setup (as Carl mentioned with the barrel jack) would work best if the signal booster has that convenient DC input jack which can be unplugged from its transformer when the power goes out, and then just plugged straight into the battery.

(Inverters also add an extra point of failure and power loss, so DC is better for simplicity and power consumption sake.)

Anne,

I think the battery box/battery generator would be more than enough to power your booster.  Most inverters can be set to 240 volts, but I suspect that is not necessary.

Earlier it was mentioned that the booster itself likely only needs a few volts and the 100-220 you mentioned meant that it could be ac powered in both Europe and the United States.  If you can find the actual dc rating I am sure we can find a way to power it without needing to go up to 220 volts just to bring it back down.

At any rate I will keep my thread updated.  I do most of the work on weekends so it might be a few days before I have a bunch more pictures.  Still, I will update as I can.

Eric

+1 to the use of a "tool line" battery inverter. We use ryobi quite heavily on the homestead, and have all kinds of batteries and chargers for them (18v, 40v), and we bought two of the inverters from ryobi that accept these battery types. Thus, double-duty for stuff you are most likely using already ... every tool line has something like this.

https://www.homedepot.com/p/RYOBI-150-Watt-Power-Inverter-for-ONE-18V-Battery-Tool-Only-RYi150BG/308460871

At a moment's notice, slap a battery (of almost any aH size) in the inverter, plug in your booster and what not, and you've got a few hours of runtime (more if you slap in another battery). Charge everything back up when the grid comes back online for you. I've left a load running on one of these all day, and it went numerous hours before the inverter cut it off due to the battery running down.

If you didn't have a tool line yet, then you'd need the inverter, a battery, and a charger ... but, and this is the crack-cocaine part, you'll want to start buying other tools in that lineup, so that you can do just about anything on the homestead, only easier (chainsaws, drills, etc.) ... you are now hooked. Not that this has ever happened to me ...

Hope this helps ...

George Yacus wrote:

Anne Miller wrote:
The signal booster shows Power Supply: Input AC 100-240 V, 50-60 Hz, Output DC 12 V/3 A.
...
Do you feel this battery generator is powerful enough to give the signal booster at least 30 min of power?

Hmmm...

12V direct current * 3amps = 36watts.  30 minutes of use would mean...

*Caution: Nerd alert below about choosing the right sized battery.*

OP's problem is likely way solved by now, but I have to take a moment to publicly shame myself in battery right-sizing.  I got my wires crossed saying "Amp-hours" instead of "watt-hours"; but even then, batteries don't do the linear math thing with amps and run time because of Peukert's Law.  In other words:

batteryguy.com website wrote:“a 5Ah battery will power a 5 amp device for one hour”. This is wrong.

Battery run time isn't just basic math of power=volts*amps.  Other factors are at play for battery sizing, including the type of battery (flooded lead-acid vs sealed vs gel etc.) and temperature among other things.  The calculator on that website would have a 4Ah 12V flooded lead battery last 0.5hour, and a 7Ah batter lasting the full hour for a 3A draw at normal-ish discharge ratings...all this not taking into account the miserable cold weather that may have knocked out the power to begin with!

(P.s. Jt's link didn't work for me, so below is an example inverter for Greenworks 40V, which I imagine is the kind Wheaton Labs likely has.)


(Source)

Not a problem George, I followed what you meant.

Eric

We've used the Yeti Goal Zero as a replacement for generators for a very long 216-mile relay foot race in the area that occurs every year. Some checkpoints have to be manned overnight and the Goal Zero powers LED floodlights from dusk to dawn. The only thing I miss about the generators and halogen lights is that about 3:00 am they gave off a little bit of heat.

Byron Campbell wrote:Hi Anne,

If your vehicle / automobile is available during the power outage, then you have a portable 12 volt DC generator (vehicle running at idle) right there. In order to have AC power, a small 12 volt DC to 120 volt AC Inverter (i.e. from Radio Shack) can be hooked up to the vehicle's battery, or plugged it into the vehicle's cigarette lighter socket, or DC ass'y jack, which will easily power a phone, or cellphone booster.

When the power fails here, I use my computer's "extended backup time" UPS system to run 120 VAC powered items. The UPS uses a pair of sealed 35 ampere "outboard" batteries. During a power outage it will run a desktop computer for 30+ minutes along with my phone system.

I was about to suggest the same thing! I heard about doing this from the Emergency Home Battery Bank  videos for sale here on permies. There's a lot of info packed into the videos on how to use car batteries for power. Since we have a generator, I didn't finish the videos, but they might be really handy for someone who wants a lot more details on how to use a car battery for power.

You have to determine how much electricity you consume in a day, and whether other devices also need power. I am currently using a Growatt infinity 1500  backup portable power supply, and the effect is ok.

George Yacus wrote:  ....... batteries don't do the linear math thing with amps and run time because of Peukert's Law.  

I hope this isn't considered hijacking Anne's OP to ask a question for my own edification.  I'm trying to learn more about charging and discharging of deep cycle batteries as I suspect in some way, shape, or form, they will be factoring large in automobile and other applications for which many of us have become accustomed to conceptualizing as petroleum powered.  This doesn't even take into account the use of batteries on the homestead for stand-alone, off-grid power.

The question being, is it fair to view Peukert's Law in the roughly same way as we've come to know that 'fuel efficiency' applied to automobiles is dependent on driving speed. Thus, if my gas mileage in my car averages 30 mpg, then under optimum driving conditions I may expect to drive 300 miles on 10 gallons of gas.  But with that same 10 gal in the tank, if I decide to drive at a faster non-optimal speed, that 10 gal likely will not get me 300 miles due to poorer mileage at the higher speed, correct?  Is this conceptually then the same as driving (discharging) in an EV at a higher than optimum speed, which in the end will shorten the distance I was *hoping* to achieve based on battery capacity and charge state?  I'm assuming there are probably calculations that additionally take into account ambient temperature that may affect batter capacity....do modern EVs have 'real-time recomputation' of capacity and anticipated range based on some of these factors?  This is probably highly elementary for many, but I'm hoping to teach my old brain some new tricks!  Thanks!....

You are really asking two questions. Does lithium battery capacity change in response to load? Unlike lead acid batteries lithiums have a set capacity that is not affected very much by the speed of discharge. That would be part one. Part two would be yes you will use more energy per km going faster than slower in a vehicle be it electric or gas powered due to the increased air resistance.
Cheers, David

Thanks, David B!  The potential for sodium ion to replace lithium ion batteries is intriguing and I hope mostly the good aspects of lithium will be found in that new technology along with potential environmental benefits and cost reductions.  As you noted, lead acid batteries suffer worse from Peukert's Law and additionally (unlike lithium iron phosphate batteries?) do not appear to exhibit as much *more* power loss under cold temperatures.  Good thing the lead acid behemoths in my golf cart beater for buzzing around the property will not be trying to push that cart against severe wind resistance -and- battling P's Law!  Thanks again!....

[Edits after noting conflicting statement on cold temperatures...]

Anne Miller wrote:Is there a simple device to make or buy to give me 30 min of power?

All I need is time to make a call to our electric company to let them know the power is out.

We have a signal booster that gives us cell phone coverage which needs power.

I am tired of buying a device that costs $500.00 to do that. Then the next time we need it no longer works.

I posted this on Jan 30 2022, the device we purchased sometime after that has gone out again.

We had tried replacing the batteries which work for a while so I am not sure how long we had the new device.

We are done spending the money.

Dear hubby is buying a deep cycle battery instead.

We have recently found some nice accessories that work without existing power-tool batteries. There are cheap and simple adaptor that you just drop your regular battery into that do various jobs. There are also adaptors that allow across-brand interchangeable battery use. We have one that converts between makita and ryobi, for example.

We now have a moderate set of ryobi batteries that are usually at various states of charge, and a bunch of different items that can be powered from them. We skipped the inverter, because we didn't need it, but have various lights, radios etc... These get used fairly regularly anyway, but also give us battery based power in the case of short term emergency need.

I particularly like that our "emergency" kit is getting regularly routine use, rather than being stashed away in box somewhere. I think we are more likely to be aware of what is working and what isn't, and the batteries are likely to be kept more regularly topped up.  Plus I don't like sinking money into equipment that ONLY has a "just in case" purpose. Multi-purpose kit is generally more valuable to have around.

Adaptor to use other batteries with ryobi tools

A ryobi battery to USB port tool - for phone charging etc...