We used to light the barn with 8 regular 100 watt bulbs - that is 800 watts of power, multiply by time and that is used to calculate your electric bill.
We now use 8 new bulbs, 24 watts each, for a total of 192 watts, and have seen a reduction in our electric usage as reported by the power company.
Illumination is about the same as far as I am concerned, and the animals have not complained a bit.
Sure, there can be unintended side effects, but was not that also said about newfangled standard bulbs when they replaced kerosene and coal oil lamps?
Mark