The Eglo Solar Lantern features a beautiful light effect. The maximum lighting duration depends on the energy of the sunlight hitting the solar panel, as well as the wattage of the lamp. Solar energy varies depending on the weather conditions and the season. The manufacturer provides the maximum possible lighting duration that can be achieved under ideal weather conditions. These maximum values decrease as less sunlight is absorbed by the solar panel. Please also note that the installed batteries cannot be replaced with standard batteries. The installed batteries are rechargeable and are charged via the solar panel. This charging process is not possible with conventional batteries.