Powering TV Without Mains Electric

[TomsFocus]

I won't bore you with the 'why' but is it possible to power a 23" TV for up to 2 hours using some sort of powerbank or similar? 

If so, what's the cheapest and easiest way to do it?  I'm guessing a solar panel in the window wouldn't produce anywhere near enough power?

The mains cord has a 19v transformer in it with a 2 pin adapter if that's any help.

Thanks,
Tom

[Paulkp]

I would go for a car battery and an inverter myself.

Does the TV have it's power consumption on the label so you can work out what the load is ?  If it has a 19V transformer, I assume the input to the TV is 19V AC ?

Digressing, I have two small solar panels in my conservatory, one charging a 12V (7Ah ?) lead acid battery in a dustbuster, and the other on a 50AH car battery.

[TomsFocus]

Thanks Paul.

I do have a few spare car batteries but can't lift them now unfortunately.  Was hoping for something lighter but good to know it's possible at least.

Do you find the solar panel effective at charging a car battery?  I've considered some rechargeable AA batteries with w solar charger but wasn't sure if it was worth it.

TV sticker:

[alexp999]

This is only 4.6 kg, but probably a bit expensive for what you are looking for:

https://uk.anker.com/collections/portable-power-stations/products/a1730?variant=41462461235364

[TomsFocus]

31 minutes ago, alexp999 said:

This is only 4.6 kg, but probably a bit expensive for what you are looking for:

https://uk.anker.com/collections/portable-power-stations/products/a1730?variant=41462461235364

Ah, now that's interesting.  Expensive yes but might be worth it.

Do you know how long something like that would power just the TV for?

[Paulkp]

Looking at the label, 19V@2.4A is about 50W, so you would need a 100-150W inverter, which if 100% efficient (which it won't be!) means about 4A@12V for that 50W power.  The power supply that you have will also have losses.  So probably about 60W from the battery, equating to a 5A input to the inverter, so for 2 Hrs, you need at least a 10Ah battery, so just in case the match goes to extra time (!) perhaps a fully charged 15-20 Ah.

Halfords have inverters around £40-50, Ring MP120 Compact Inverter looks neat, and CPC have an 18AH battery that weigh about 5kg for £35.  A 063 car battery is about 12kg.

I have two of the smallest maplin solar panels, with the one on the car battery left permanently connected, last time I looked it was at about 12.7V, but when I get a chance I'll put some load on it and see how it is.

[alexp999]

5 minutes ago, TomsFocus said:

Ah, now that's interesting.  Expensive yes but might be worth it.

Do you know how long something like that would power just the TV for?

It has a 388.8Wh battery, so taking Paul's assumption above of 60W draw for the TV, then about 6 hrs.

[alexp999]

It does look like it's a 110V output though, so check your TV power adapter has full range input. You may also need an adapter, I can't tell what the AC socket type is.

[Paulkp]

Digressing - I don't think any battery capacity could be specified to four significant figures !

[alexp999]

The amazon listing says 230V and review pictures show a UK socket though:

https://www.amazon.co.uk/Anker-PowerHouse-Portable-Generator-Emergency/dp/B08PCYF3Y4

[TomsFocus]

It does indeed look like separate models for UK & US.  As you say, the 3 pin is shown on amazon.

Paul's idea of small battery and inverter are also very interesting.  My latest car battery weighs 20kg...I thought it was a typo until it was delivered!  Had to ask someone else to move it for me lol.

Hmm, decisions....

[erictcleric]

Does it have to be that specific TV? You could get a caravan TV that runs off a 12V car battery, which might work out cheaper than a power bank and inverter - example:

https://www.amazon.co.uk/Westinghouse-12v-Caravan-Satellite-Tuner/dp/B08KJDFT7B/ref=mp_s_a_1_11?crid=30HUH4OEN9LU1&keywords=caravan+tv&qid=1646812617&sprefix=%2Caps%2C73&sr=8-11

[TomsFocus]

Yes, it does have to be this TV.

Cost isn't as important as ease & the appearance of nothing having changed when the mains power is off.  So with that in mind, I'll go for the Anker listed above at the current £320 offer price.  Unless anyone can recommend a better equivalent by about lunchtime today.

Of course, being an amazon sale, I can always return it within a month if it doesn't work in the desired way too.   

[Paulkp]

It looks a nice piece of kit, and a single box solution.

[unofix]

The simple answer is just to use a 'UPS' (uninterruptible power supply) of about 1500VA / 900W

typical cost is £180 and weight is approx 10 Kg

Just do a Google search on 'Mains UPS 900W' and there are hundreds to choose from.

An example from amazon (not the cheapest of places):

https://www.amazon.co.uk/Tripp-Lite-Line-Interactive-Battery-OMNIVSX1500/dp/B07NH39QGN

[Paulkp]

UPS is also a possible solution, and will come in useful to support your land line when BT turn you digital !

I have an aversion to using a UPS - mainly due to operating and maintaining experience with early devices. I once built up quite a stock of 7Ah/12V batteries that smart UPSs reported as failed, but for my purposes seemed to work OK for years !

And I agree, Amazonis not the cheapest of sources.

 

[TomsFocus]

10Kg is still too heavy now I've tested it.  I'm looking at about 3Kg being reliably 'manageable' now.  Hoping the Anker is just about liftable on a good day at 4.6Kg and have ordered one of those now.

Aside from the extra wattage (allowing higher powered devices to run presumably?), what would have been the benefit of a UPS out of interest?  

[unofix]

16 minutes ago, TomsFocus said:

benefit of a UPS out of interest

Simple to use, 'plug in - switch on - and use' It will automatically switch between mains supply when available and then swap to battery when the mains goes off. It also recharges it's own batteries so basically it's a fit and forget solution if you require continues power for a device.

I doubt if you will be able to find any device weighing under 4Kg that will have enough power to run your TV for 2 hours due to the energy to mass ratio of conventional batteries.

[TomsFocus]

8 minutes ago, unofix said:

Simple to use, 'plug in - switch on - and use' It will automatically switch between mains supply when available and then swap to battery when the mains goes off. It also recharges it's own batteries so basically it's a fit and forget solution if you require continues power for a device.

I doubt if you will be able to find any device weighing under 4Kg that will have enough power to run your TV for 2 hours due to the energy to mass ratio of conventional batteries.

Ah, I see, thanks. 

I don't have space for a permanent fixture next to the socket so that wouldn't be suitable for this particular situation.  (Hence the need to be liftable.)  I can see it would be useful for things like medical equipment and temp critical meds though.

[StephenFord]

Gosh, this thread takes me back LOL 50 odd years ago, we had a 10" B&W TV powered by a car battery set up in my nan's caravan! Of course, in those days, the caravan had no electric whatsoever, and lighting was from gas mantles - I'm very old 🤣

[Jimpster]

Look into Cpap batteries/power packs, they will run a Cpap for 24-48hrs, i think one is called an Atom. For those camping travelling and need their devices overnight. Allegedly rechargeable in a number of ways.

[TomsFocus]

**UPDATE**

The Anker arrived yesterday.  First impressions, seems very well built...but is pretty heavy!  (Although that's subjective of course!). 

It does have a 3 pin plug as pictured.  So I assume that means it'll be 230v.  Hope to charge it up later today on cheap electric and then give it a try. 

[TomsFocus]

You'll have to excuse the shocking contrast quality on my phone camera but I can confirm that it powers the TV fine.

Takes 40w when running, estimated 8.5 hours.  Though a very short test appears to use roughly 1% every 5 mins.

Surprisingly, the TV takes 9w when 'Off'.  It has touch buttons only, no physical button, so will take some power all the time but I didn't expect that much.

 

Now, aside from the weight, there is one downside.  It makes quite a loud 'charging' type buzz...when powering through the 3 pin socket.  It doesn't make any noise at all when being charged.   Will that be down to the AC inverter?  It's probably not a noise most people would be bothered by, but I am extremely sensitive to any noise at the moment.  (Was deaf in one ear for most of 2018/19...think I preferred that lol!)

[Paulkp]

Good to see a successful solution.  I'm not familiar with modern inverters, but I would think the "buzz" is from the inverter output, with perhaps a  transformer vibrating at 50Hz.

The 9W (40mA @ 240V) does not sound particularly excessive, as there are losses in the TV power supply converting the 240V to 19V for the TV, and in addition, there is the power into the TV standby circuit.  And if I read the label on the back of the TV, it was built in 2011, so there would have been efficiency improvements since then.  If you have a remote for the TV, then you will also be powering the remote control circuits.

Enjoy you viewing !

[Paulkp]

On 3/8/2022 at 3:30 PM, TomsFocus said:

Do you find the solar panel effective at charging a car battery?  I've considered some rechargeable AA batteries with w solar charger but wasn't sure if it was worth it.

 

This is what I have got :

Two of the smallest panels from Maplin, one charging a 7Ah battery in the "dustbuster" and the other an old Fiesta battery.  Dust buster works well, it originally came with a car accesory lead, but I stuck in a battery and connector for charging.  Being as Maplin went bust years ago, you can see that they are quite old.  I had used one on the parcel shelf in my Puma Thunder, (I still miss it!!!) and never had a problem with a flat battery.

(See my earlier post....

I have an aversion to using a UPS - mainly due to operating and maintaining experience with early devices. I once built up quite a stock of 7Ah/12V batteries that smart UPSs reported as failed, but for my purposes seemed to work OK for years !)

Car battery seems Ok, I did a simple test on this and two of my car batteries, still got two to do !

Simple bench battery testing can be done by connecting a suitable load, in my case a 55W bulb in a spare Fiesta foglight unit to the battery. First measure the no load volts, NLV, connect the load, and measure the on load volts, OLV, and load current, LC.

Internal Resistance = (NLV-OLV)/LC = Ohms

This gives you an idea of battery condition.  When the battery is in the car, you can get a vague idea by measuring the volts, then turning on a few headlights ! With the engine off !

Results
Solar Battery:

No load Volts =12.3
On load Volts =11.1
Load Current = 4.2

Internal Resistance = (12.3-11.1)/4.2 = 286 mOhms

Fiesta Battery:
No load Volts =12.4
On load Volts =11.7
Load Current = 4.33

Internal Resistance = (12.4-11.7)/4.33 = 162 0mOhms

Focus Battery:

No load Volts = 12.3
On load Volts =11.5
Load Current = 4.3

Internal Resistance = (12.3-11.5)/4.3 = 186 mOhms

So, not a perfect test, but a good indication.  I think the Focus (60Ah ?) is the newest battery of the three, Fiesta is 52Ah, and the solar 43Ah.  Solar has worst figure, but it is the smallest and the oldest !