My husband rearranged my plant room with new seedling shelves and new LED plant lights. I have a small closet in the garage with it’s own thermostat that I use for seed starting.
Shelves: This year, my husband set it up with two large Home Depot metal shelf units. They are on wheels so I can move the front one to access the one in the back. I raise so many seedlings between my home gardens and my Pantry Garden/Farm that I have been filling my shelves to capacity the past few years. It will be interesting to see if I can fill up these two new big shelves.
Fluorescent Lights: I have always run fluorescent tube lights on my plant shelves. I used shop light fixtures with two 40 watt bulbs per fixture, two fixtures per shelf, seven shelves. At 120 volts, a single 40 Watt bulb draws 0.8 amps of current, that whole set of shelves was drawing about (0.8 watt/bulb x 4 bulbs/shelf x 7 shelves =) 22.4 amp. And there goes the 20 amp circuit breaker. For safety, I’ve been splitting the lights between two GFI circuits, which trip at about 5 amps, and, not so safely, one 20amp circuit. I’ve resisted switching to LED because the bulbs and fixtures are so more expensive. Fluorescent tubes have cost me only about $8 per bulb and lasted a couple years. It’s hard to calculate a fair comparison between fluorescent and LED with several parameters (cost/bulb, bulb life, lumens/amp) involved. But one thing is sure, if I can stop blowing my fuses I’ll be happy.
LED Lights: My new lights are LED utility lights (made by Commercial Electric and sold at Home Depot) that come with four light tubes per fixture and are designed to be linked up to 4 in a series, so there’s one benefit already. We bought four fixtures and I don’t have tangled cords all over the place like I used to. The manual for the lights says each four-bulb unit (one shelf) draws a current 0.8 amps at 120 volts. That’s 25% of the current my that fluorescent tubes drew. So, yes!, I should be able to run them all and use only (8 shelves x 0.8 amps/shelf =) 6.4 amps, which I can split between two GFI circuits! Yeah.
But now comes the comparison of the amount of light produced by the fluorescent versus LED tubes, which is based on the Wattage of the bulbs. Each shelf of my fluorescent set-up had four 40 Watt tubes at 120 volts, so 160 Watts per shelf. My 0.8 amp LED light fixtures at 120 volts produce 100 Watts total per shelf. Not much different. But the big benefit of LED is that it is so much brighter per Watt than fluorescent. About four-times more lumens per Watt. So my LED lights are about 2.5 time brighter than my old fluorescent light. I used to keep my lights 1-2 inched from mt seedlings, but I should be able move these further away, which means I can probably situate the plant trays sideways and fit four tray’s per shelf. Exciting! I can’t do more calculations, so I’ll experiment to figure out the rest.