According to the specs on the light, it pulls roughly 250-260 watts at the wall. If I remember correctly you want a MINIMUM of around 35watts per sq ft of canopy putting you at about a 7 sq ft of coverage, although that is a stretch. for best results I would probably aim closer to 4-5sq ft. How many plants you can grow depends On their genetics and how big they will get!! With Autos, generally speaking I wouldn’t do more than 3 in that space IMO. Keep in mind you want to give them a lil breathing room. Just cause you can cram more plants in doesn’t mean you should!