required lightning

Area is what matters and number of plants does not. Number of plants will impact how much vege time you need to fill the area, but not requirements of light for that area. Your hours of operation matters. So, whether you grow photoperiods or not will have a big impact on what you need. Based on 12hours per day, you are capped at about 800-900PPFD... this is an upper 30's DLI range (daily light integral). Your daily light integral allows an apples to apples comparison of energy applied to the plant regardless of area or hours of operation. Simply put, 35-40DLI will have the same results over 12 hours as 18 hours, ceteris paribus. Read the wiki. Get the gist. It's important to understand the causality here to avoid the nonsense you'll read and hear over the years. Efficacy of grow lights varies, so using watts per square foot has inherent pitfalls and inconsistencies. Stick to DLI. It's a better, smaller ballpark to start in. Shoot for 35-40DLI and then observe and react to plant to fine tune power and hanging distance -- hanging distance should be more about geometry of your coverage, but is an available tool to impact light intensity at canopy, too. All suggestions will requires some trial and error, and using DLI will be the least amount of trial and error to get to a good point. Luckily, witha 100x100 area, that's just 1 meter-square, so you don't even need to do any math for PPFD. The umol/s of you rlight will be the PPFD if hung a proper distance to focus the light in the most even way across your 100x100 canopy. So any light that puts out 800-900 umol/s (per your 1m^2) is your PPFD. Then, reference that with hours of operations with a DLI table that you can easily google. how efficacy can significantly impact this... takes 2.3umol/J vs 2.8umol/J 900 / 2.8 = about 320 watts with a high efficacy light can produce 900PPFD in your 1m^2 tent context 900 / 2.3 = about 390 watts needed... if you look up old HID lighting and the 50w/sq ft suggestion that was fairly consistent because of regulations in making a bulb. Whether due to some shady lobbyist group of the industry or not, the consistency allowed for the use of watts per sq foot and it worked well... it does not anymore. Some lights are drastically more efficient at producing light than others. A 70-watt difference can be seen in the example above and that's just for a small 1m^2 area. .07kw x 12 x 60 + (.66 * .07) *18 * 40 = 83.664 kW-H extra for a 40day vege on 18h cycle and a 60 day bloom on 12 hour cycle... That's only a 17 USD difference in 1 grow cycle around here. YMMV based on local cost of electricity. An area 4x as big that's a 60 USD difference every grow cycle... 4x a year... it can add up. over 10 years of use you'll spend 600 more on the less efficient light. you can see why spending a 100 more at point of sale is worth it for a high quality light. This topic is only debatable if you don't actually know the details... it can seem complicated, but it is not. Local variables will make for different "max" DLI... temps, humidity and more importantly atmospheric CO2 will dictate how much your plants can handle... not your choice in lights, though it should match the variables. My sugestion is easily converted for an autoflower grower ... adjust inverse proportionally to hours of operations. 18 - 12 is simply 12/18 or 67% over 18hours comes out to the same DLI. So, 600PPFD is about all you need for autoflowers in a 1m^2 tentn with 18hour cycle. (2/3rds of 900PPFD above) Turns out education is quite useful daily.