A 24-hour light cycle is not as beneficial as many people believe it to be. While under light rays plants multitask, the energy they take in from the light is split up and used in a number of different ways and only part of it goes to growth. During hours of darkness plants rely on the stored energy they took in from the light, which was diverted from plant growth while under light, and they shut down most functions and almost all the plant’s energy goes for plant growth.
Plants grow much more efficiently at night than during the day, a much higher percentage of the energy it uses at night goes to growth than it does during the day. So in spite of what many people inaccurately believe a 24-hour light cycle is not the best way to go. 18/6 is a better option and it will somewhat cut down on your energy consumption too.