Electrical Emergency Battery Backup System for TV/Internet During Power Outages

[bob012345]

TL;DR Summary

Considerations for design of an emergency battery backup system for TV/Internet during power outages.

I am looking for the right size of battery/pure sine-wave inverter to power a system for a few hour when there is a power outage. The system of TV/DVD/Internet uses less than 200 watts at about 1.6Amps. I could just buy a commercial system which runs about 1000$ or assemble a similar design for about one-half to one-third the cost. Any thoughts?

 

[berkeman]

My first thought is why do you need a full-size TV during power outages? Just use a smaller UPS to power your wireless modem and use your phones instead to watch TV. Think "low power"...

Edit/Add -- I think my small UPS that I use to back up our Xfinity wireless router cost about $150-$200, and it holds up for a few hours at least. I also have separate batteries that I use for running our HAM radios and recharging USB devices during power outages.

 

[bob012345]

My first thought is why do you need a full-size TV during power outages? Just use a smaller UPS to power your wireless modem and use your phones instead to watch TV. Think "low power"...

Thanks. Yes, that would work but it is not so much a need as a want because I have experienced a number of frustrating outages over the years and I got to the point of wanting to have a sense of normalcy during those times. For example, I want to have lamps that light up like normal room lamps, a device to power the microwave so I can cook dinner, a device to turn on the TV, ect. I could just buy a power-wall or a large generator but that gets to several thousand dollars.

 

[berkeman]

Agreed. We live in Silicon Valley, California (actually in the foothills above the Valley), so we have been experiencing several on-purpose PG&E "Public Safety Power Shutoff" events per year lately (for fire safety during high fire danger periods with high winds). Definitely a pain in the rear.

A bigger issue for us is how to do the best we can at keeping the refrigerator/freezer food cold and not letting it spoil.

 

[bob012345]

Agreed. We live in Silicon Valley, California (actually in the foothills above the Valley), so we have been experiencing several on-purpose PG&E "Public Safety Power Shutoff" events per year lately (for fire safety during high fire danger periods with high winds). Definitely a pain in the rear.

A bigger issue for us is how to do the best we can at keeping the refrigerator/freezer food cold and not letting it spoil.

What do you do now to keep food safe during outages? When I lost power during the Texas Deep Freeze last year I could just set my food outside in a bag. I plan on getting a garage freezer and having lot of thermal mass of ice to keep food cold in general like in summertime during an outage.

 

[berkeman]

When possible, get ice for several ice chests and if the outage lasts long enough, move the perishables to the ice chests. Try to keep the fridge/freezer closed as much as possible too, obviously. Some of the neighbors in our HOA run generators to power their fridges, but that's a bit noisy and you have to keep a fair amount of fuel around to power the fridge for several days in a row...

 

[bob012345]

There are natural gas powered whole house generators available that automatically switch on during an outage but they cost several thousand and are generally not worth it unless disruptions become a way of life and one prioritizes that sense of normalcy or if there are medical reasons to keep power on.

 

[bob012345]

In general I feel like I have to plan on there being a bit less stability in the future than in the past just because our society and it's technology base is so complex and our problems are large.

 

[Vanadium 50]

Before going down this path...

Do you even have internet when the power goes out? When I lose power, so does my cable company.

 

[berkeman]

Do you even have internet when the power goes out?

I do. I was a bit surprised, but I guess the Xfinity feeds up into our foothills area are self-powered, not relying on local power here in the foothills.

OTOH, this may be a bit of a unique situation here, since the Valley floor typically is not shut off for PG&E PSPS events, just the foothills and farther east get shut off. So it may not help if your typical power outages also involve the central office or distribution points for your Internet connection.

 

[bob012345]

Before going down this path...

Do you even have internet when the power goes out? When I lose power, so does my cable company.

I believe so because my outages are usually very local. I think the cable signal is like my phone land line, always on but of course I need to power the cable equipment which I believe a battery will do. At least I could watch a DVD.

 

[anorlunda]

In general I feel like I have to plan on there being a bit less stability in the future than in the past just because our society and it's technology base is so complex and our problems are large.

If you're planning for post apocalyptic life, a battery won't get you very far.

 

[berkeman]

If you're planning for post apocalyptic life, a battery won't get you very far.

That depends...

https://academic.hep.com.cn//article/2012/2095-1701/2095-1701-6-3-210/thumbnail/hcm0000454589.jpg

 

[bob012345]

If you're planning for post apocalyptic life, a battery won't get you very far.

That's why I only said a little bit less stability which is not at all apocalyptic. It means things like a 2 hour power outage just when I was about to cook dinner and watch another episode of Stargate Atlantis.

 

[anorlunda]

That's why I only said a little bit less stability which is not at all apocalyptic. It means things like a 2 hour power outage just when I was about to cook dinner and watch another episode of Stargate Atlantis.

In that case, a UPS (uninterruptable power supply) is the simplest solution. Many brands are available at several capacities to suit your needs.

But you have to think it through. It is easy to UPS your TV and Internet. It is much harder to UPS an electric stove to cook dinner. Perhaps you have a gas stove or a propane grill out on the patio.

 

[Rive]

A bigger issue for us is how to do the best we can at keeping the refrigerator/freezer food cold and not letting it spoil.

Different part of the world, but same problems. We already has a small UPS to keep the light and small stuff running, and a small generator is on the schedule to 'charge' the fridge in need.
As the calculation goes, just two hours a day would be able to keep the freezer freezed and the UPS charged.

 

[bob012345]

In that case, a UPS (uninterruptable power supply) is the simplest solution. Many brands are available at several capacities to suit your needs.

But you have to think it through. It is easy to UPS your TV and Internet. It is much harder to UPS an electric stove to cook dinner. Perhaps you have a gas stove or a propane grill out on the patio

The system I envision for the tv could power the microwave for tv dinners also. It would be foolish to try and power electric stoves. Yes, many ways are available to cook without electricity. I used old Sterno cans to heat soup during the Texas Deep Freeze.

 

[berkeman]

As the calculation goes, just two hours a day would be able to keep the freezer freezed and the UPS charged.

Yeah, that has to be the right strategy, I think. My neighbors who leave their generators on continuously are wasting gas, probably.

 

[bob012345]

In that case, a UPS (uninterruptable power supply) is the simplest solution. Many brands are available at several capacities to suit your needs.

I am not sure how to interpret this;

• 600VA / 330W Backup Battery power supply

I am used to battery specified in Amp-hrs and volts such as 12V and 100A-hrs.

 

[bob012345]

Before going down this path...

Do you even have internet when the power goes out? When I lose power, so does my cable company.

Now I'm not so sure my cable will work if the my block is down. I have to ask the company.

 

[Borek]

I want to have lamps that light up like normal room lamps, a device to power the microwave so I can cook dinner, a device to turn on the TV, ect.

That puts your power needs in kW area, which also means several kWh storage.

I could just buy a power-wall or a large generator but that gets to several thousand dollars.

And in kW/kWh area I doubt you will get much cheaper.

 

[bob012345]

Now I'm not so sure my cable will work if the my block is down. I have to ask the company.

I called the cable company. They said as long as it's not a power outage on their end but just my local area my backup power should work to keep the tv/internet going.

 

[bob012345]

That puts your power needs in kW area, which also means several kWh storage.

I don't mean doing everything at once. But you are correct for the microwave the battery would have to supply power at 1kw for 5-10 minutes. That may not be worth the money to do.

 

[berkeman]

I don't mean doing everything at once. But you are correct for the microwave the battery would have to supply power at 1kw for 5-10 minutes. That may not be worth the money to do.

There are some pretty tasty self-heating MREs lately...

https://www.thereadystore.com/mre-self-heating-emergency-meal-case-of-12

 

[tech99]

In general I feel like I have to plan on there being a bit less stability in the future than in the past just because our society and it's technology base is so complex and our problems are large.

I agree with your view on this. Reliance on technology seems to have created the spiral we find ourselves in. The back-up system is only a sticking plaster on the injury. Could we live happily without Internet, freezer and TV?

 

[berkeman]

I agree with your view on this. Reliance on technology seems to have created the spiral we find ourselves in. The back-up system is only a sticking plaster on the injury. Could we live happily without Internet, freezer and TV?

Okay, no freezer. More MREs...

 

[Vanadium 50]

I called the cable company. They said

How do you know when your cable company is lying to you? Their lips are moving.

I had better luck with outages when I had IDSL. The phone company was (and is) pretty far away.

 

[symbolipoint]

But you have to think it through. It is easy to UPS your TV and Internet. It is much harder to UPS an electric stove to cook dinner. Perhaps you have a gas stove or a propane grill out on the patio.

One might choose a grill or a barbecue type device, or for some people, some vintage equipment running on kerosene.

 

[symbolipoint]

(Only up to page 1 of this topic)

Saw no comment or response yet about solar power generators or chargers. Maybe are their effectiveness too limited?

 

[Borek]

(Only up to page 1 of this topic)

Saw no comment or response yet about solar power generators or chargers. Maybe are their effectiveness too limited?

Somehow I doubt power outages will happen only during sunny weather, which puts us back at the storage problem.

 

[Rive]

Could we live happily without Internet, freezer and TV?

Well. It may taking the issue on larger scale, but I think internet will more and more become a critical infrastructure in the future, with the TV being reduced to be a bit bigger monitor only. So for the former, it's a no.
And that includes the mobile phones too.

Regarding the freezer - without those most people would be dependent on the grocery stores and their fresh supply. Is that fundamentally better/different?

 

[symbolipoint]

Somehow I doubt power outages will happen only during sunny weather, which puts us back at the storage problem.

The idea is , store during the day and possibly use whenever - daylight or nighttime.

 

[Vanadium 50]

Saw no comment or response yet about solar power generators or chargers.

If $1000 is too much, how much energy is he going to be able to store from solar?

 

[bob012345]

I agree with your view on this. Reliance on technology seems to have created the spiral we find ourselves in. The back-up system is only a sticking plaster on the injury. Could we live happily without Internet, freezer and TV?

There was a day when people were content reading newspapers and felt they were connected to the world.

 

[bob012345]

(Only up to page 1 of this topic)

Saw no comment or response yet about solar power generators or chargers. Maybe are their effectiveness too limited?

They work and there are solar cookers too which work. There are also cooking techniques we can borrow from other cultures which stretch the available cooking power of the sun or fuels used such as hay baskets. So cooking is not a problem.

The next level on my proposed battery backup system for TV is a solar charger in case of an extended outage lasting many days but if it were due to rolling outages which is the most likely scenario, there would be intermittent wall power to charge the batteries so that seems unnecessary.

 

[bob012345]

Regarding the freezer - without those most people would be dependent on the grocery stores and their fresh supply. Is that fundamentally better/different?

Canned goods and dry goods are reliable old standby's too. Up until the pandemic I generally kept very little food at the house in any form, a few days only. I have since expanded that to a few weeks.

 

[bob012345]

If $1000 is too much, how much energy is he going to be able to store from solar?

That referred to my thought that the ready to go in one box commercial system just seemed overpriced and one could assemble an equivalent system for less not that I could not spend that if I chose to. That commercial system has a solar charging option for another $300 but again I think a much higher price for the same amount of solar panels one could buy without the brand.

In the end I might decide I am lazy enough to just buy the commercial system though...

 

[Grinkle]

I suggest you make a specific list of what you want to power, what power it consumes and how long you want to power it.

If you have a patio, buy a propane campstove (Amazon, Wal-Mart, commonly available) and some 1 lb propane containers (brick and mortar stores only, these are not shipping friendly) for cooking. That will cost you in the neighborhood of $75 and be much more straightforward than powering a microwave - also you can heat water with the stove for doing dishes. If you have a large enough patio, you can store a 20lb or 10lb propane tank there and not mess with the 1lb bottles which are disposable as opposed to re-fillable and so relatively more eco-unfriendly.

If you get your list down to your original post, modem, TV, DVD then I think the previous suggestion of battery backup is your best bet. If you end up wanting to run you normal household lights that is a big step up in complexity and imo not worth bothering with.

Regarding -

I am not sure how to interpret this;

• 600VA / 330W Backup Battery power supply

I think this is a 3A@110V max output device and a capacity of 600VA, so if drawing 3A@110RMS continuously the system will be at 0 charge after 2 hours. (300 VA's per hour being drained). I would de-rate my own personal expectations on that capacity by about 50%.

 

[bob012345]

I suggest you make a specific list of what you want to power, what power it consumes and how long you want to power it.

If you have a patio, buy a propane campstove (Amazon, Wal-Mart, commonly available) and some 1 lb propane containers (brick and mortar stores only, these are not shipping friendly) for cooking. That will cost you in the neighborhood of $75 and be much more straightforward than powering a microwave - also you can heat water with the stove for doing dishes. If you have a large enough patio, you can store a 20lb or 10lb propane tank there and not mess with the 1lb bottles which are disposable as opposed to re-fillable and so relatively more eco-unfriendly.

If you get your list down to your original post, modem, TV, DVD then I think the previous suggestion of battery backup is your best bet. If you end up wanting to run you normal household lights that is a big step up in complexity and imo not worth bothering with.

Regarding -
I think this is a 3A@110V max output device and a capacity of 600VA, so if drawing 3A@110RMS continuously the system will be at 0 charge after 2 hours. (300 VA's per hour being drained). I would de-rate my own personal expectations on that capacity by about 50%.

Good suggestions. As far as lights go, not the whole house but a couple of lamps with low wattage LED lamps running on smaller batteries for ~5-10 hours per charge. Of course flashlights as backup for that and candles as backup for that...

 

[Tom.G]

I am not sure how to interpret this;

• 600VA / 330W Backup Battery power supply

The 330W is the peak power the system can supply before either blowing an internal fuse or shutting down from an overload.

The 600VA is the maximum reactive power to avoid shutting down. Motors, for instance, and many computer power supplies have a large reactive component in their loading.

The run-time of a battery back-up is limited by the battery capacity. For instance I am using a commercial 750 VA/450W UPS to run the computer I'm typing this on. That's over powered by a factor of about 2 but it will take a larger battery.

The battery in it is rated 12V 9AH 14AH and a new battery gives about 15 minutes of run time (about 1/2 to1/3 of what you expect from the battery size alone); but running it that long is so hard on the battery that I'm lucky to get 8 minutes on the next cycle.

Also, I replace the battery when the run time from the self-test drops to 75% of a new battery. I find that the battery degrades rapidly beyond that point. That means the battery gets replaced after about 3 2 years of very light usage, costing a little over USD$1 per month - or 3 to 4 cents a day.

Sure beats a day or three of trying to recover from a computer crash!

Cheers,
Tom
Edit: battery size and lifetime 1/23/2022

 

[Grinkle]

The 600VA is the maximum reactive power to avoid shutting down.

That makes sense - I saw that spec stated as "capacity" on Amazon, hence my incorrect reasoning.

 

[russ_watters]

There was a day when people were content reading newspapers and felt they were connected to the world.

For years I have mentioned to my mom what I read in tomorrow's newspaper and no matter how many times I explain it to her, she never understands it.

 

[sophiecentaur]

wanting to have a sense of normalcy during those times

It could be that regular failing electricity supply will actually be 'normalcy' before too long. Look around the World.
I have a wood burner which provides enough heat for the lower floor and I have heated water on the top of it. Forget the telly - read a book or play board games. AA cells will last a long time in LED torches.
I was thinking that people with electric cars have a significant amount of stored energy. If your daily timetable would support it, that could be a useful band aid.

 

[anorlunda]

We use batteryuniversity.com as the vendor-independent source for reliable and comprehensive information about batteries.

It would be nice to have an analogous source for power backup and/or off-grid household advice. UPS supplies, portable generators, fixed generators, safety, grid interface, plus info on the frequency and duration of possible outages would all be topics covered.

Lacking that, each homeowner makes haphazard, and perhaps ineffective, overblown, or even hazardous individual decisions.

Vendor sources, such as Honda, or Kohler of course discuss only the use of their own products.

Does anyone know of such a source that we could cite here on PF?

 

[bob012345]

It could be that regular failing electricity supply will actually be 'normalcy' before too long. Look around the World.
I have a wood burner which provides enough heat for the lower floor and I have heated water on the top of it. Forget the telly - read a book or play board games. AA cells will last a long time in LED torches.
I was thinking that people with electric cars have a significant amount of stored energy. If your daily timetable would support it, that could be a useful band aid.

If it does it would induce people to counter that by redesigning the system to be resilient and taking individual responsibility for energy needs to the extent possible and reasonable. I am in a local group of renewable energy advocates and enthusiasts. Some members apply various solutions to energy use and generation from energy efficiency, battery backup, solar panels all the way up to net zero houses. Groups like that can be found or started almost anywhere.

 

[Laroxe]

I was growing live food for my aquariums in a 60 gallon tank outside, which I needed to keep the temp above freezing, my very rough, ready and cheap solution was;
A 200w solar panel kit for charging batteries which included a charge controller which cost around £40
A 600w power inverter - 12v to 240v (uk) cost £30
I got 2 second hand truck batteries from a scrapyard, ordinary lead acid rated at 110 ah each for £20 each.
Really, the better choice is deep cycle batteries, these are much better at providing continuous power, but these are expensive.
I had an old 240 volt aquarium heater- thermostat which I used. That worked fine for the grand total of £110, I had to replace one of the batteries after 2 years
You would need a more powerful system & it would be easier if you dropped the microwave requirement but people are able to use quite a lot of things in camper vans and caravans, it might be useful to see if you can find where they go to die. You can even find used deep cycle batteries that come from things like fork lift trucks on eBay. You shouldn't need to pay a fortune for a backup system, but you might have to be flexible in your requirements.

 

[anorlunda]

Some members apply various solutions to energy use and generation from energy efficiency, battery backup, solar panels all the way up to net zero houses. Groups like that can be found or started almost anywhere.

Nearly 50% of the population live in multiple family, or even high rise buildings. Their options are limited compared to those with private houses.

 

[bob012345]

Nearly 50% of the population live in multiple family, or even high rise buildings. Their options are limited compared to those with private houses.

Renters are not always renters forever and they have a stake in the energy infrastructure. They can join groups and learn about technology and policy and have an influence on society in general not to mention on the rental market itself. Efficiency and waste are not the sole domain of homeowners.

 

[sophiecentaur]

A 200w solar panel kit for charging batteries which included a charge controller which cost around £40
A 600w power inverter - 12v to 240v (uk) cost £30
I got 2 second hand truck batteries from a scrapyard, ordinary lead acid rated at 110 ah each for £20 each.
Really, the better choice is deep cycle batteries, these are much better at providing continuous power, but these are expensive.
I had an old 240 volt aquarium heater- thermostat which I used. That worked fine for the grand total of £110, I had to replace one of the batteries after 2 years

For that relatively small scale installation you probably got a good solution. For storing a large number of kWhr, the electrical storage may not be best. (Depending on your actual situation, of course). But why use a mains voltage heater? There are plenty of low voltage heaters (or even car headlamp bulbs) about and no inverter would be necessary.

For home heating and washing water, no significant electric power is needed.Thermal solar panels can be home-made and can 'charge up' a large, well insulated tank of water. Keeping temperatures low (downside is that needs a lot of stored water) reduces losses. There are also solar heat panels which are very efficient, even in 'cold' weather conditions.

 

[Rive]

Forget the telly - read a book or play board games. AA cells will last a long time in LED torches.

Yes. I'm a bit confused about that microwave oven thing of this topic too. To have the necessary capacity and power due a few minutes of excess load is not really a good solution by my book.

Regarding those torches - there are already flashlights with Li-ion battery and USB connector. They can cut back material consumption (batteries) some really nicely.