I also have no experience with these lights, but in reading your post, I was wondering why you were not including LED lights, as they have no mercury and are supposedly more cost-efficient than even the CFLs?

Well let's see:

1. I'm 70 years old and played with mercury as a kid rubbing it on coins, rolling it around between my hands, and dropping it on the floor to watch it scatter into teeny tiny little beads so a wimpy little CFL bulb with a whisper of mercury in it isn't going to scare me.

2. I'm not including LEDs because the startup costs are high, and as I mentioned before I'm 70 years old and who knows how long I'll last to defray the costs since after all I played with mercury as a child....

3. as you say, you have no experience with CFLs but you are decidely against them. So, I guess this means if I keel over from residual childhood mercury poisoning, I guess you don't want me to leave you the 50 CFL bulbs in my will?

@ delaware(Z7 DE) The Mercury is indeed an issue for me, even though I am also above 70 years old, not because of the imminent contamination of my self, but because of the ongoing contamination of the environment. I have used the CFLs in my home and have not been at all impressed with their reliability. I have since gone to LEDs and have been very happy with them. When I build a system requiring lights I will use LEDs.
And yes, you have my permission to will your 50 CFLs to anyone else but me, Thank you.
I admire your wit. Hope to interact with you again!

just a couple of things for you to consider.

for most plants, germination doesn't require light. light doesn't become a factor until the first "real" leaves start to appear. when the plant first sprouts you'll see 2 green things that look like leaves, these are cotyledons. they are part of the seed, and contain all the nutrients the plant will require until the first leave appear. so, you might save some money by turning the lights out on the seed germination area.

I'm not sure if growing outdoors is an option for you, but it will save significantly on your electric costs if you can provide sunlight instead of electrical light.

I grow my hydro plants, herbs and veggies, outdoors with no supplemental lighting, but I'm in California, where the weather is mild.

if I had to grow my plants indoors, the cost of electricity would cost more than buying my herbs and veggies at a store. I have good yields, but not $50 per month.

of course growing my own plants, and knowing exactly what's in them, and on them, like no pesticides, would allow me to justify a higher cost. but how much higher? that would be a tough decision.

you two crack me up.

i'm sorry, but the ONLY calculator anyone knowing actual wattage needs is whatever device or grey matter is used to multiply:

(Wattage × Hrs × Days × kWhRate$) / 1000 = price

Furthermore: unless trying to HEAT your plants, wattage doesn't tell you...anything! Lumens offers some approximation, although ability to place lights close up to plant or only further without frying them (depends on efficiency - less watts per lumen means less heat; smaller wattages per bulb and efficient heat dispersal, such as in bare spiral CFLs or LED bulbs, also add up to a cooler bulb with more close-up capabilities)

Mercury - only matters if you break the bulb, and get the innards all over the place. Anyways, it's more of a disposal regulation issue than a health warning... I don't even see Prop 65 warnings on cali bulbs, and that known to the state of cali to cause cancer sticker is on EVERYTHING these days

LEDs - uh, I can get ~280,000 lumens worth of any mixture of 3000K & 5000K LED lights / $1000 spent at my local cali grocer...semi-decent brand, even, not GE/Silvania mind you, but also not some noname newcomer. That's not all that expensive, and actually comes in bluish temp veg lights too, not just 2700-3000K "soft white" yellow flowering lights like all cheap CFLs

in fact, current "affordable" vegging lights in CFL cost as much or MORE per lumen than LED...though admittedly good discount scores to the tune of 5000-10,000 lumens / dollar in CFL 2700k can't be beat, providing a whopping 5-10 MILLION lumens / $1000 spent (somewhat deceptive since you'll spend 10x the price on fixtures, but still...mindblowing!)

economy wise:

good LED ~90-100 lumens/watt

crap LED ~60 lumens/watt (IKEA/intertek junk)

good CFL ~65-70 lumens/watt

bad CFL ~40 lumens/watt (again with the IKEA/intertek junk)

thus, good CFL outperforms bad LEDs in not just price, but also in efficiency...

additionally, good CFLs are furthermore cheapened by pumping more lumens per bulb, with monster bulbs doing 2500-5000 on normal sockets (vs 900 or so for affordable LED), providing major savings on fixtures/splitters

though there is absolutely no way you can actually mount $1000 of discount CFLs...youd probably be visible from outer space for the few milliseconds before you simultaneously blow the grid and your eyeballs ^_^

yup theyre THAT cheap. might as well consider 2700K cfl to be a) free,b) a nobrainer... but LED too is already giving MH & HPS a run for its money, and is actually available at perfect vegging colour temps for the same price. might as well mix and match!

BUT... efficiency ain't all it's made out to be, at least not outside summer

an overly efficient LED/CFL rig, despite tenting and insulation, may well find itself in need of a couple hundred "wasted heat watts", such as 2-3 halogen or incandescent bulbs, to keep temperature optimal during cold nights...or, as the case may be for herbs and tropicals, forget optimal - try survivable

PS all lights and other electrical equipment, heaters included, radiate nearly the same heat per wattage pulled. high-wattage inefficient bulbs are thus on par with any other heater except gas-fired furnaces...which is not to say they perform the exact same. for example, halogen reflectors emit a narrow beam of heat, while clear incandescents heat all around them, and cloudy white painted incandescents heat themselves to a greater degree, focusing more heat close to their surfaces. [all this makes halogen floodlights "better" for heat - but trickier to get right... those using a number of these might also consider a small metal halide instead, for the added bonus of tangible amounts of useful light output for the same heat & wattage specs]

I'm just starting out but here are the calculations for my hydroponic/led lighting setup.

I have 3 LED lights that have two settings a 170 watt "Grow" and a 260 watt "Bloom" setting that adds additional red spectrum. They are illuminating a hydroponic setup of 8 towers using the NFT technique and the lighting seem to be covering it well. I have two lights set to 260 watts and the third to 170 for a total of 690 watts.

I'm running the lights on a 17 hours on and 7 hours off cycle so I'm using 690 * 17 = 11,730 watts a day OR about 350 kWh a month.

I'm paying about $0.15 /kWh so that works out to $52/month for electricity.

Since I have 8 towers, each tower uses about $2 / week in electricity. So my goal is trying to get each tower to produce at least $2 worth of food each week.

Why only factor in your lighting costs if you're gonna to do a cost analysis? Electricity may not even be you highest cost on an individual basis. Water pumps, air pumps, nutes, water, additives, pH adjusting supplies, etc. obviously all add to the cost. I know people who spend way more on nutes/additives alone per month than what you're spending on electricity. To each their own but if you're going to set a goal in order to offset costs it should probably be on all the costs or it's just a bit arbitrary.

Yes, you're right, it's just to give me a rough idea of what I need to get out. I'm still figuring out my nutrient needs but it looks like electricity will be the biggest ongoing cost for me. Nutrients probably about $5-10/month