Television screens are getting bigger... and so are electricity bills
Flat-screen TVs - a Christmas "must-have" in many households - are among the latest gadgets to be black-listed by environmentalists for their heavy power consumption. But are they really the 4x4s of home entertainment?
By Sean Coughlan
BBC News Magazine
They're big and bright and flying off the shelves in the seasonal spending spree. Flat-screen televisions are accounting for eight out of 10 TVs bought this Christmas - casting their bulky old predecessors into the shade.
But while the cash tills might be ringing, there have been warnings about the environmental impact of this big-screen switch-over.
According to the government-funded Energy Saving Trust, plasma televisions which are 50% bigger than their cathode-ray tube equivalents "consume about four times more energy".
In terms of carbon emissions, the EST says old-style TVs produce 100kg of climate-warming CO2 per year - while larger, plasma screens (there are no small plasma TVs) will pump out 400kg.
Flat-screen televisions are a big seller this Christmas
Supporting these claims, the EST points to research from the government-funded Market Transformation Programme, which advises the government on sustainability policy.
This says that, on average, the power consumption of a cathode-ray screen is 3.4 watts per screen inch, while plasma uses 9.4 watts per screen inch - based on figures from 2005.
So does that make these sleek new TVs the gas-guzzling 4x4s of home entertainment?
Not exactly. Flat-screen TVs broadly come in two varieties - plasma (which go from about 42ins to an almost cinematic 100ins-plus, and LCD, which are smaller, but, crucially, getting bigger all the time).
Peter Raynes, professor of opto-electronic engineering at the University of Oxford, says modern LCD screens use a similar amount of power to bulky old cathode ray tube (CRT) televisions.
Old-style televisions are on the way out
Plasma televisions are currently less efficient and will use more power, he says.
But Professor Raynes cautions about the difficulty in objectively comparing like with like - because there are unlikely to be any CRT televisions on the High Street which are the same size as plasma.
Manufacturer Philips, which makes CRT, LCD and plasma televisions, even rejects the broad assumption that plasma screens are inherently more power hungry - a spokesperson saying there was no clear, standardised, consensus on energy use.
And with rapid advances in technology, power consumption for all screens is set to become more efficient - rendering any current forecasts redundant.
But is this really about technology or about consumers hankering after bigger and bigger TVs?
The stand-by button can undermine any attempt at energy efficiency
The specifications from Philips' range shows how much it's the upscaling in size that matters - and also how difficult it is to generalise about power consumption.
Philips has won a European green television of the year award with its 42ins LCD television - which has a power consumption of 210 watts. In comparison, a 42ins plasma screen uses 230 watts. Not much different? Well, there's another plasma screen, the same size, same manufacturer, which uses 365 watts.
Then look at Philips' old-style televisions, where a medium-size 28ins widescreen only uses 87 watts and a portable 39 watts. And an LCD portable uses 42 watts.
And the 50ins plasma screen? A bumper-size 400 watts.
So you can be eco-conscious, buy the "green telly of the year", and still end up using twice as much energy as the old box you've thrown out. Confusing?
John Twidell, adviser on energy to the Institute of Physics, says consumers need to be given much more straightforward information about power consumption.
Another key issue for energy consumption, says Dr Twidell, is turning off machines at the mains - and avoiding leaving televisions on stand-by. There's no point worrying about economising, if a television on stand-by is chewing up the power all day and night, every day.
There are other issues surrounding television energy consumption - such as the brightness of screens.
The Market Transformation Programme warns that televisions are often set for display in shops, rather than the much lower levels of light needed for home use.
It suggests that creating an "eco-mode" for screen brightness could cut power consumption by 15%.
And disposing of the unwanted CRT televisions is going to be a challenge in itself - with an anticipated 70 million old-style sets to be dumped by the end of the decade.
Once you've sorted out the power, there's still an even bigger question. Where do you put a 50ins flat-screen television in your living room?
Add your comments on this story, using the form below.
I was in an electrical retail shop last week - not to buy a mega-silly TV. But I reckon plasma TVs can save CO2 emissions and energy because if I had one I would never need my central heating on. They get so hot I felt like I was in the tropics in the TV section.
Our notion of progress seems to be getting rather warped these days. We are expected to dump old TVs (no recycling available) then buy new ones that use too much power, take up too much space, presumably boom out the 'high-quality' sound even louder so that it annoys neighbours through the thin walls of the poorly-built modern flat/house you've paid too much for.
Sometimes I'm hopeful that we will be able to turn away from the environmental crisis we are heading for, but then I read stories like this and reality hits me in the face again. Surely there must be a balance between enjoying yourself and being environmentally responsible as well? I just hope that the manufacturers of these televisions are working hard to reduce their energy consumption. Let's all take some responsiblity for the future of our planet.
Lucy Turner, Eastbourne
Who cares about how much power they consume? I know I don't. It doesn't matter what you do, there's always somebody sticking their oar in, whinging about eco this and eco that. If they're that concerned about it, why don't they develop a TV that doesn't use as much power. I have a 42" Plasma, it's switched off at the mains at night watched for 25 mins while I get ready for work and about 4 hours on an evening after my evening meal. The majority of people are not like these un-employed people who buy TV's like this from credit companies and sit on their rears all day watching Trisha and eating pot noodles, pumping out children all year so they don't have to work. I paid for my TV outright, I can buy what I want to buy when I want to buy it and use it how I see fit (within reason of course!)
I've just been trying to compare the running costs of LCD and CRT computer monitors. The accessible monitors in my workplace don't display power ratings, nor is it at all easy to find the price of a kilowatt-hour online, despite the numerous so-called 'energy comparison' websites. If this dearth of information is typical, how are we to make environmentally-friendly buying choices? As usual, there is an urgent need for stringent, simple and standardised labelling of goods and services.
Jason Mills, Accrington
I've got a 4 year old 42" plasma screen which I was amazed to find out pulls 4.3 Amps which is 1032 Watts! I've just purchased a new LCD TV which only uses 185 Watts of power which will save me almost £1000 in electricity over 5 years and reduce my contribution to CO2 emissions.
I am a service engineer, a standard 42" Plasma screen at normal settings for home use, should consume around 300watts of power. Most of this is lost as heat. Improvements in design can hugely reduce this but add to the cost. If demand is apparent manufacturers will respond. So ask for a low energy set.
Robin Metcalfe, Sheffield
A lot of plasmas have an energy save option which subtly turns down the brightness. Beyond that it heats the room so meaning less use of central heating, so it's not all bad.
Our previous colour TV, a modest 26 inch CRT, used 850 watts. Our current 28 inch CRT uses 220 watts. Time always brings efficiency in the consumer electronics market, so be patient. However, plasma will never be as energy efficient as LCD due to its screen heat losses generated by the individual plasma bulbs.
Alan Jones, Lee on the Solent
A standby feature is included in appliances because turning off all current in the circuitry compromises the longevity of certain components. No standby means more failure, more replacements and larger CO2 footprints.
My flatmate often turns our TV to standby then walks up to it and puts the remote control on top of it! It is so frustrating. Manufacturers can help by taking away the standby feature, but in the meantime people need to change their lazy habits - and it saves money!
I don't understand this fixation with huge screens. I have a 28" CRT and it dominates the room already - and the picture still outperforms any LCD/Plasma I've seen.
Why can't you turn off TVs using the remote rather than only being able to put it on stand-by? I often put it on stand-by meaning to then turn it off, but then forget.
Julie Sadler, Leeds
Please, please, please, can somebody shut these people up? Why, in this age of modern technology can we not enjoy the 'fruits of our labours'? I am now the owner of a 42" plasma screen, and wonder how I managed before. The picture is better in all ways, and my electricity bill has hardly changed - so where does the extra energy come from?
With a mature, modern and science-based policy on nuclear power, we could all have televisions as large as we wanted with no need for the guilt. Environmental lobbyists need to realise that, since the 'energy footprint' of each UK citizen is going to rise over time regardless of how many energy saving lightbulbs we all buy or how many acres of countryside we will have covered with wind turbines in 50 years time, they need to embrace the solutions we have right now, and issue loud demands for their implementation. Nuclear energy will save this planet; whinging about televisions and pining after vague 'alternatives' will condemn us all.
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