Power Consumption of Televisions & Monitors

Television uses some 9.5% of the energy used by the average Aussie home. I suspect that this portion is even higher in 'stand alone' home power systems since they would not be using air con, electric heating etc. While LCD & plasma televisions are more efficient than the old style CRT type televisions, the total power used has not decreased because the screen size is increasing and more households are getting multiple televisions.

Increasing television efficiency is an important factor in reducing our carbon footprint (considering there are 18,000,000 TV's in Australia - 2,000,000 are sold annually).

The good news for the consumer is that all new TVs imported into Australia should have a Star label. The Star label rates the TV from 1 to 10 stars and gives the expected power used per year assuming the TV is on for 10 hours a day (!).

One of my favourite websites (www.energyrating.gov.au) lists all TV's – if you go to TV's and click on the comprehensive data tab, you can see what each TV uses in run mode, on standby, per year etc. You can sort the results by the number of Stars, manufacturers, etc.

The September issue of Choice magazine tested a couple of dozen 102 - 107cm televisions for picture quality as well as power consumption.

These types of television were tested:

• Plasma
• LCD / CCFL backlighting
• LCD / LED backlighting

The average plasma used 138 watts and the older style LCD/CCFL used 139.5 watts. The good news is that the newer LCD/LED type averaged 91.5 watts. That is a substantial 34% energy saving.

Of the 21 seven and eight Star televisions listed at www.energyrating.gov.au, 19 are of the new LCD/LED type.

Generally, these new televisions and computer monitors have ‘LED' type written on the glossy labels.

With the increasing value of our dollar, they reckon Christmas time will be an ideal time to buy imported electronics. Might be time to put a TV in the Christmas stocking.

Power Consumption of small TV sets

There is a wide variety of televisions on the market. The now old-fashioned television is referred to as a CRT (cathode ray tube). Plasma and LCD televisions are now standard and a LED TV set would be the 'new kid on the block'!

LCD televisions have the advantage of taking up a lot less space. They are only 50-75 mm thick. Another advantage is that they use about one third less energy than the same size CRT television.

A 34 cm (14") Sony CRT television was measured to use 58 watts. I recently checked the energy consumption of a 43cm (17") LCD wide screen television (NEC brand), and found that it used 53 watts when measured on the AC side.

Interestingly, a lot of LCD televisions (including the NEC model above), work on an input of 12 volts. One brand, Majestic, is advertised as such, and the specifications advise that it will work between 10.9 and 15.5 volts. However, I would not advise that you attempt to run any other brand direct off the battery unless the distributor/service centre for that brand television advises that it is okay. The battery voltage on a solar system can typically range from 10.5 to 15 volts (for a so-called 12V system). It could even operate outside of this range under certain fault conditions (eg a flat battery or say the television is running direct off the panels if the battery is disconnected.) Given the cost of an LCD television, I'd suggest is is better to be safe than sorry.

The power pack for the NEC television is rated a 5 amps 12 volts DC. I am not certain whether or not it would work off a modified square wave inverter as opposed to a battery quality sine wave inverter.

Power Consumption of large TV sets

For small/medium size televisions, LCD is clearly the choice for those of you with limited power. The other great news is that they are getting cheaper as time goes on. Coles and a number of supermarkets are now selling 38 cm LCD televisions for under AUS$200.

All the LCD televisions (at least up to 51 cm) actually work on a 12V power supply (from a 230V plug pack).

They are incredibly efficient if you can run them directly from 12V.

I say 'if' because they are designed to run off a 230V-12V regulated power supply. This is not the same as running it direct from a 12V solar system where the battery voltage can easily range from 11 to 15 volts. An even wider variance is possible with flat or failing batteries; a battery system being equalised to 15.5-16 volts etc.

There appears to be a few brands that can definitely be run off a battery and these are marketed to the caravan and yachting market. Majestic LCD televisions will operate between 10.9 and 15.5 volts. Xien sell a range for the marine industry. Sharp televisions are also sold as '12 volts' but come with a $140 special 12 V lead. I suggest this has a power conditioner on it. Dick Smith once sold (and may still do so) an AC/DC 15 inch model.

Most people assume that all the brands would operate satisfactorily but we are unable to recommend this without information from the manufacturers. If any of you have information or experience in this regard, please let me know.

The power 'saving' of being able to run it direct is significant. From my observations, the 230 to 12V adapter supplied with the television is only about 50% efficient. By the time you then use an inverter to change your 12V to 230V, I estimate that you could be tripling your power consumption.

For those of you on 24 volts, an efficient 24 to 12V converter is a reasonable option. I tested the 15" Music TV using our 8A voltage reducer (APX-006 - discontinued) and it used a modest 1 amp on 24 volts.

For the 'big end of town', a consumer magazine tested 4 popular brands of large LCD and Plasma televisions for power consumption. Interestingly, the 45/ 46 inch Plasma televisions used 260 –286 watts while the 42/43 inch Plasma televisions used significantly less (183- 186 watts). All four used between 0.67 and 1.4 watts on stand by.

There are four main types of televisions available now and some power consumption's that we know about are listed below:

Cathode Ray Television (CRT), also known as 'the Box'BrandSize (inch)Consumptionmeasured onrunningstandbySony Trinitron1428W230VDaewoo1439W230VDaewoo2079W230VPhilips2140W230VLiquid Crystal Display LCD TelevisionBrandSize (inch)Consumptionmeasured onrunningstandbyXien76W12VXien88W12VXien1215W12VXien1515W12VXien1725W12VXien2148W12VMusic TV1522W12VMusic TV1525W24VNEC1753W230VTyagi2440W230VTyagi2440W12VSamsumg2695-105W0.7W230VSamsumg46286W230VMagnavox2695W2W230VJVC3195W - 164Wtypical 120W0.22W230VSharp45261W230V

Note: 17, 45 and 46" are wide screen format

The power used by LCD television sets varies significantly with the brightness settings (particularly the back light brightness settings).

For example the 31" JVC varied between 100W & 200W depending on how bright you set your screen.

Plasma TelevisionBrandSize (inch)Consumptionmeasured onrunningstandbyPanasonic34165-200W230VPanasonic42240W230VPioneer43186W230VSony42183W230V

Note: The Panasonic models tested were 1-2 years old. I’m not certain if their higher wattage is due to older technology or brand differences.

LED TelevisionBrandSize (inch)Consumptionmeasured onrunningstandbyKogan2432W1W12VPanasonic TH-40CS610A4040W0.2W230V

It is claimed that LED screens offer significant power savings over both LCD and plasma televisions. Energy-efficient backlighting allows LED televisions to have energy consumption of up to 40 percent less than LCD televisions and significantly less than a plasma screen. But there are two types of LED screens.

Benefits of LED and RGB Dynamic LEDs vs Edge-LEDs

I read in one of the tests that The local dimming LED TVs used quite a bit more power than a traditional LCD TV in the same screen size. This type of LED television approaches plasma displays in power usage. The edge lit LED televisions use less power than an LCD of the same size.

1. Edge lit LED
2. LCD TV (fluorescent)
3. Local dimming LED

LED screens are still significantly dearer, but are superior in image quality, light in weight, extremely thin.

Conclusion: In the small/medium size television range, LCD has the lowest power consumption; however, it is not known if all brands can be run directly from a ‘solar battery’ system. In the very large size, Plasma televisions appear to be more energy efficient than LCD. Many televisions use power on standby unless they are switched off at the power-point.

Power Consumption of DVD & VCR

I recently tested a 230 Volt DVD Home Theatre Surround System. For those of you like myself who are still coming to grips with modern technology, this new type of sound system broadcasts the sound to six different speaker channels. This is sometimes referred to as DTS 5.1 surround sound. Gone are the days of two channel stereo sound!

These units typically boast a 200-400W sound output. However, music watts are not the same as electrical watts. The compliance label for my 200W unit suggested a power consumption of 72 watts. However, when measured with a watt meter, it used 9W on standby and when playing it used about 33 watts, occasionally peaking to 46W when playing Pink Floyd's 'The Wall' on full volume! This wattage does not include the power used by the television to broadcast the picture.

I also tested a VCR. It used 6.2W on standby and 14W when playing. The compliance label suggested 18 watts. This was a conventional unit which relied on the television to broadcast the sound. I'd suggest that a DVD player which similarly used the television speakers would also only use around 14 watts.

Power Consumption of Blue Ray®

I have bought myself an early Christmas present – a Sony Blu-Ray DVD Home Theatre System. It has many features including 1000W total output power, 5.1 Surround Sound, and 3D capability. Two of the 6 speakers are operated by a separate wireless surround amplifier rated at 50W according to the compliance label. The main amplifier is rated at 130 watts.

So I was fearing the worst – that my sound system would use more power than my 80cm LCD television (120W).

I am pleased to report that it used substantially less than what the compliance labels read. The wireless surround amplifier used about 2 watts on standby and 9 – 10 watts when operating. The main player/amplifier used 2 – 3 watts on stand-by and between 27 - 30 watts powering the sound from the television (from soft to loud).

When playing a DVD, it used between 27 watts and 60 watts. At 60 watts the sound level was unbearably loud in my small lounge room. All in all, I would suggest that it uses a total of about 40 watts at a normal sound volume.

I am also happy yo say I am very pleased with my new present – a recent magazine review rated the Sony as their first choice based on several factors.

Austar Satellite Decoder

Austar is a pay television option in Australia and New Zealand, which is delivered by satellite to a receiver dish on your roof (about 70cm diameter) to a decoder, which is connected to your TV. An Austar technician can complete the installation in about 1-hour.

The 'basic' service gives you some 29 channels including ABC & SBS plus 25 radio channels. I believe it is similar (identical?) to FOX TV. The reception/picture and sound quality on all channels can only be described as 'perfect' - no snow, waves, shadows etc!

Well, now that I have the ad out of the way - lets look at the electrical requirements! If my TV is the only load on my SA22 Selectronic 1600W inverter, it draws 3.6A @ 25 volts and 3.8A with the Austar decoder on. When measured with a 30A resistive load on the inverter, the TV on its own draws 3.0A and 4.0A with the Austar decoder on. When the wattage of the decoder is measured on the AC side, my meter read between 10 and 12 watts. The efficiency of the Selectronic inverter, even running at around 5% of its capacity is quite remarkable! In my case, the TV is often the only night-time load on my inverter, so the extra 0.2 amp required by the decoder is quite insignificant! Incidentally, the compliance label on the decoder suggests the maximum power is 0.35A @ 230V (84 watts) and the label on my TV suggests 78 watts.

Power Consumption of large Sound System

One of our customers recently did an energy audit on his rather large and sophisticated sound system.

Generally we have found that audio equipment uses a lot less power than what the specification would have you believe. Many amplifiers use more power when the volume is turned up high.

We would suggest that you use a sine wave inverter for running your audio equipment. A modified square wave inverter often causes an unacceptable buzz or hum on audio equipment.

A battery operated radio or CD player is the most power efficient form of audio equipment if you have a limited size solar system. Power consumption of even the larger models is usually only 3 to 6 watts. This is more efficient than running a 230 Volt unit from an inverter.

Murray measured the following power consumption's of his audio equipment. If you were running it from an inverter, you would need to add around 15% extra for inverter losses.

1. Audio Aero Capitole 24/192 CD Player. Standby; 31.6 watts (W) Playing; 33.7 watts (W) Not really affected by volume. Claimed energy consumption; 30 watts

2. Opera Audio Cyber-800 Power Amps (2). Standby (on - not really standby) 165W each Playing; 165 -175W each. Not really affected by volume. Claimed energy consumption; 90W each

3. Opera Audio Consonance R1.1 Reference Pre-amplifier. Standby; 13.7W Playing; 14W Not really affected by volume. Claimed energy consumption; 40W

4. Opera Audio Consonance C3 three channel power amp. Standby; 42W (on - not really standby) Low volume; 44W Med volume; 60W Loud volume; 100 – 130W

5. Yamaha RX-V2400 AV Receiver. Standby; 59W Low volume; 59W Med volume; 62W Loud volume; 63W Claimed energy consumption; 500W - as an amplifier - I only use as a receiver.

6. Denon CDR-W1500 CD Recorder. Standby; 15.5W Playing; 20W Claimed power consumption; 29W

7. Marantz DV4300 DVD Player. Standby; 2.7W Playing; 16W Claimed power consumption; 14W

8. Panasonic DMR-E100H DVD Recorder. Standby; 4.1W Playing; 37W Claimed energy usage; 45W

9. Paradigm Servo 15 powered Sub woofer. Standby; 2.3W On; 25-55W