The energy label of a product indicates how energy-efficient a product is with electricity. The energy labels run from A (dark green) to G (dark red), where lamps with energy label A are the most efficient and those with label G are the least efficient. You can find the energy label under specifications - light source.
Since the implementation of the new strict requirements for energy labels in September 2021, light sources have been given a relatively low energy rating. E, F and G are usually the energy labels that light sources are given, but they are just as economical as A, A+ or A++ used to be.
The energy consumption is shown at the bottom of the energy label on the product packaging. This is shown in kWh per 1000 hours. LED lights are often the most energy efficient light bulbs available.