Hello All, So, I am attempting to finalize my hydroponic lettuce production design. Let's just talk about obtaining enough light for a 5x5 flat area that will be packed with lettuce in every part of the 5x5 (forget about the spacing, etc). I think the best lighting solution for that is two 2x4 work lights next to each other that together hold eight 48", 32watt, T8 bulbs, and another 48" fixture that holds two 48" bulbs for a total of 10 bulbs at 32watts each. Links to the items found below. So, assuming I want to stack this system 5 times... that equates to 50 lights. NOW, let's say i set up this system and turn on the lights for one month, assuming the price is .8¢ per kWh, each light is on for 16hrs/day for 31 days at 496hrs total for each light, that equates to $634.88/month. Holy Crap. Can someone smarter than me please tell me if I'm wrong or how to reduce this or a much cheaper way of properly providing enough light to a 5x5 area of lettuce??? Does each bulb have to be 32watts to make them grow fast or can i have them each be 4watts? Thanks So Much! Manny Shop Metalux 49-1/8" Utility Fluorescent Lighting at Lowes.com and 48 in. Shop Light - Tools - Garage Organization & Shelving - Work Lights
A 1000w light which covers a 5x5 area will raise your bill 75-120 a month depending on where you live IMO.
Lettuce is a low-light plant. I believe you need to 20-25 watts per square foot. 1 tier of your design being 320 watts is then divided by your square footage, right? So 4x4 = 16 feet, then we take 320 watts / 16 feet and arrive at 20 watts per square foot if I am thinking clearly. If this is accurate, you are at your minimum for good lettuce growth, but would not be able to grow, say...tomatoes, very well. Yeah, that does seem expensive for a crop as cheap as lettuce. You would need to grow a boatload to get anywhere close to breaking even on the expense, but if you were growing clones or seedlings of a more valuable crop for sale, it may be logical.
i use 2 48'' floros 2 24'' floros and a 400 hps for flowering and only about a 60$ change that includes my two pump and 2 fans