MEPS
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Televisions April 2005
Page 9
A study produced for the Energy Efficiency and Conservation Authority by
Wise Analysis Ltd
advent of remote switching controls made it imperative that the voltage was removed by a solid
state switching device, able to be turned on by the remote control. But this “holding off” uses
power itself, and when the TV is in this mode it is termed “passive standby” or just standby. In
this report where standby is used it means passive standby. The same technology is used for
other remote controlled devices such as set top boxes.
(a) Standard Cathode Ray Tube (CRT)
As noted in 2.1, most existing televisions in Australia and New Zealand use cathode ray tube
(CRT) technology and these existing televisions are usually set up to receive analogue
broadcasts. CRT TVs can be purchased in standard (4:3) or wide screen format (16:9).
The features provided by a TV affect the power usage. The features on a CRT TV that have
most impact on power (with the mean effect in brackets
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Huenges Wajer et al
6
) are 100 Hz
picture frequency (37.8W), stereo sound (11.5W), surround sound (15.2W), second tuner
(12.2W), satellite tuner (10.1W). Not all these features are offered in New Zealand. Screen size
itself has a relatively minor effect.
(b) Slimline televisions
While the sales volume of slimline televisions in New Zealand in 2003 was 5.2% compared
with 95% CRT, by 2004 this had increased to 9.6% slimline televisions. Sales of LCD TVs in
Australia have also been low to date, largely because of their cost, but recent improvements to
LCD technology and an international trend toward LCD televisions may see prices fall and the
market share increase. LCD televisions boast lower energy consumption levels compared with
other television types. For example the NAEEEC Store Survey measurements showed a mean-
in-use power of 56.4W for LCD sets compared with 79.1W for CRT sets.
(i)
Liquid Crystal Display (LCD)
LCD televisions utilise the same technology as computer monitors and until very recently have
had smaller screens than conventional full sized CRT technology and plasma units. They were
also considerably more expensive than CRT technology, comparable size for size with plasma
screens. However, LCD televisions are brighter, crisper, and have a better contrast ratio and a
better viewing angle compared to plasma units and a much greater life expectancy.
(ii) Plasma Screens and TVs
In simple terms plasma screens are made up of lots of tiny fluorescent lights to produce a high
quality image for television viewing. The technology allows for a greater viewing angle - 160
degrees compared to about 60 degrees in the standard CRT televisions. As such, it isn’t
necessary to be directly in front of the television to be able to view the picture. Plasma screens
boast a wide-screen format, light weight and low radiation compared to CRT television types.
Many of the plasma screens available require a set top box, VCR or home theatre package to
produce images, as they do not contain a TV tuner, although more models are now being
produced that do contain an integrated digital or analogue tuner. Plasma televisions are plasma
screens with built in television tuners.
6
Huenges Wajer B.P.F., Siderius P.J.S.,
Analysis of Energy Consumption and Efficiency Potential for TVs in on-mode, EC report November
1998
http://www.vhknet.com/download/TV_on-mode_final_report.pdf