18 MAY 05

I'm looking out of our bathroom window for the first time and loving it: the rising multiple trunks and lush foliage of our tree complemented by a clear view of one of Clapham's more unusual buildings, an elegant Wesleyian mission hall with a suspiciously Masonic triangularity of form. Unfortunately, however, the bathroom window itself is missing, as is the ceiling, the floor above and the roof above that.

Once again we're way behind schedule thanks to some unruly steel that has twice been sent back for refabrication. The house appears to mount a vigorous immune response whenever this thoroughly un-eco, un-tree like component is thrust into the heart of our timber frame. I could weep into my fairtrade coffee but instead I am focussing on some of the finer details of our 'zero carbon' specification; this week I headed for London's west end in search of another domestic view, the all important window on the world offered by our beloved television sets. Could the finest of London’s retailers tell me about their energy performance, I wondered?

First stop, John Lewis, where I was assured that all televisions had 'minimal' electricity consumption so I needn't worry. The same adjective was used by the impatient assistant in House of Fraser, who compared televisions to irons, evidently a symbol for him of domestic inconsequence. In fact, we would need a clutch of extra power stations if televisions performed as badly as power-hungry irons.

The cheerless assistant in Selfridges began in the same vein but did tell me that plasma televisions use more electricity than either traditional cathode ray tube (CRT) sets or liquid crystal display (LCD) flat screens. He then showed me three Sharp LCD televisions which actually had energy labels stuck to them, albeit so discretely they needed pointing out. He evidently felt that this information would adequately represent the rest of his stock.

In Tottenham Court Road, I tried a Sony specialist where my questions were met with incredulity. Power consumption? Was I going abroad? Finally, a few doors up at PNR Audiovision, patient and cheerful Minesh finally took my questions seriously and did a good job of answering them, even downloading and printing out information from the internet to enable cross-brand comparison. He showed me the labels on the Sharp televisions but didn't assume they were representative of all brands (in fact, Sharp is a market leader in energy efficiency).

For the record, televisions do not consume 'minimal' electricity. Screens have grown and stretched, as has our time in front of them (and perhaps our bellies too), so they take a fair slice of the domestic energy cake. The bigger your screen, the more power you draw, but power consumption also varies across technologies and brands. As plasma screens are shameless gas-guzzlers, the competition is really between LCDs and traditional CRTs.

Although LCDs have gained a reputation for energy efficiency, this is only a sure bet for smaller, computer-sized screens. Above 18 inches CRTs are still winning, though not consistently. For example, a 32inch Sharp widescreen CRT television has a power consumption of only 85W, compared to 135W for a flat LCD screen of the same size. But this isn’t really comparing like with like: a 'pure flat' Sharp CRT has an even higher consumption of 160W (what a difference a little curvature makes). Given that the future is flat, it looks like LCDs may be the long-term favourites after all.

Hopefully Sharp's energy labelling will be followed by other brands, so that quick comparisons can be made on the shop floor. The leading brands are committed to this so it's time they delivered. Remember to check the standby consumption too, which ought not to be more than 1W, as even the most diligent among us still forget to get up and turn the thing off.

If you're interested in the energy label on a fridge, take the same interest in any electronic goods you buy. If a few more people start asking these questions, those high street looks of patronising incredulity might slowly begin to fade.