Chrisq writes: An EU study has found that many electronic devices and appliances use more energy in real-world conditions than in the standard EU tests. Often the real world figures are double those in the ratings. Sometimes this is achieved by having various optional features switched off during the test. For example, switching on modern TV features such as "ultra-high definition" and "high-dynamic range" in real-world test cycles boosted energy use in four out of seven televisions surveyed -- one by more than 100%. However some appliances appear to have "defeat devices" built in, with some Samsung TVs appearing to recognize the standard testing clip: "The Swedish Energy Agency's Testlab has come across televisions that clearly recognize the standard film (IEC) used for testing," says the letter, which the Guardian has seen. "These displays immediately lower their energy use by adjusting the brightness of the display when the standard film is being run. This is a way of avoiding the market surveillance authorities and should be addressed by the commission."