A recent study aimed to measure how much energy smartphone chargers consume when left plugged in continuously. The researchers tested seven different chargers, including a 65W Asus laptop charger and six smartphone chargers with power ratings ranging from 10W to 120W. These chargers were from well-known brands like Huawei, Motorola, Honor, and Xiaomi. All were connected to a power strip linked to an energy cost meter to accurately track their consumption. The test was conducted over a 12-hour period, from 6:00 PM to 6:00 AM. The total energy consumed by all seven chargers was measured at 0.07Wh, which translates to about 51.1Wh per year. This is roughly equivalent to the battery capacity of an entry-level laptop, like the Asus VivoBook Go 15. Based on an average electricity price of €0.2516 per kWh, this would cost about €0.013 per year, or just 1.3 cents annually. The study also identified a potential issue with the measurement tool used. The energy meter had a tolerance of plus or minus 0.3 W for power readings below 3 W. During the test, the meter recorded a maximum of 0.434 W, with most readings below 0.25 W. To account for possible inaccuracies, the researchers recalculated the consumption assuming a continuous use of 0.6 W per charger. Even under this "extreme" assumption, the annual cost would be around €1.33, far below the €12.09 that would be needed to make leaving chargers plugged in 11% of an EDF electricity bill. While the energy cost is negligible, the study highlights other reasons to unplug chargers when not in use. Some lower-quality chargers, especially those not made by recognized brands, may not meet safety standards and can overheat, even when no device is connected. This heating could, over time, damage internal components or, in very rare cases, cause fires. However, the chargers used in the experiment from well-known brands showed minimal temperature increase—only about 1.5°C above room temperature—after being left plugged in for over 24 hours. The study recommends choosing chargers from reputable brands to ensure both safety and efficiency. If a device comes without a charger, it is advised to purchase one from a recognized manufacturer or trusted third-party brands like Ugreen, Anker, or Baseus. This ensures better performance and reduces potential risks.