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Unusually for a modern TV, the bodywork of Sony's 40in KDL-40WE5 is white. But actually, it should probably have been green. For Sony reckons that the 40WE5 is not only its most eco-friendly TV yet, but also one of the 'greenest' TVs ever built by anyone. And for once, these claims seem to have some grounding in fact!
To put some numbers on Sony's claims, the brand's own 40in KDL-40W4500 consumes around 205W of power, while the 40WE5 consumes only 88W. I suspect the difference wouldn't be quite so marked if you compared the 40WE5 with Sony's newer 40W5500 - but even so, there's no doubt whatsoever that the 88W claim is pretty remarkable for such a large TV. In fact, it means the 40WE5 can consume far less power than nearly all 32in TVs, and even a few 26in models.
So how has Sony managed to keep power consumption so low? Well, the two most important innovations have to be the introduction of a new backlight system, and a groundbreaking 'Presence Sensor'.
The new backlight ditches the conventional CCFL approach in favour of the world's first micro-tubular Hot Cathode Fluorescent Lamp (HCFL) backlight system. This move alone is reckoned to deliver a 50 per cent power reduction versus Sony's previous LCD TV models.
The Presence Sensor is, perhaps, a bit more gimmicky - but no less interesting. It comprises a little sensor on the TV's fascia that can detect both movement and body heat, so that if you walk out of the room without remembering to turn your 40WE5 off, the TV will realise you're no longer there and turn the picture off automatically after a designated time. The sound will continue to play, so that you can still hear your programme from another room, but the picture won't come on again until the Presence Sensor detects you re-entering the room.
I found the Presence Sensor surprisingly effective during my tests. It certainly proved very adept at recognising when nobody was in the room, turning off its pictures accordingly. It wasn't quite so good, for some reason, at spotting when I came back into the room, only activating pictures again right away for around 90 per cent of the time. But heck, even if the picture doesn't miraculously pop on again as soon as you re-enter the room, it only takes a quick press of the remote to get things up and running again.
The 40WE5's other 'green' features are less innovative/practical, but we should cover them nonetheless. And so we find a general Eco image preset, which optimises various aspects of the 40WE5's pictures to get the maximum energy 'value' from the TV. More specific Eco features include a light sensor mode that adjusts the picture settings in response to the light levels of your viewing room (a feature common to most LCD TVs these days); an 'Idle' mode where the TV can turn itself off if you don't do anything to it after a preset time; and a PC Power Management mode that switches the TV to standby if no signal is received from a computer for 30 seconds.
On top of all this, the 40WE5 uses an onscreen instructions manual to save on the paper required for a printed one, and is the first Bravia TV to feature a full manual 'off' switch, which leaves the TV using virtually no power at all.
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