Like @Covertgrower I went down the high efficacy LED route and built 3 fixtures to replace my (nine!) blurple lights in a 4 X 6 space. I went from; 1,340 plug watts of China lights to a peak of 720 between all three fixtures and have yet to run higher than around 600 watts. So; less than half my previous utility bill and the last 3 plant grow delivered just shy of 2 pounds of flower. Running roughly 25 watts/square foot with a rate of 1.25 grams per watt.
Do not cheap out on lights. Do your research. THE most highly regarded LED’s produced are from HLG.