EnderG60;1045035 wrote: even with electricity and bulb replacement they are still cheaper to run.
That can't be true.
The cheapest MH fixture I can find is $120 and then the bulbs are $50/year. I've factored in electricity costs based on $0.12/kW (average for Atlanta) and a 10 hour/day schedule. For the record, i'm ignoring additional costs on AC from the heat that would be generated, ignoring the additional costs of making more water from the higher evaporation, ignoring anything you have to do to keep the tank temperature down and I'm also assuming your ballast is running at 100% efficiency (it's not).
In this example, I'm comparing 1 150W MH to 1 a360W Kessil LED. From what I've seen from PAR meters, they are comparable.
MH startup = $120
Year 1 = $50 bulb + $5.40 energy bill
Year 2 = $50 bulb + $5.40 energy bill
Year 3 = $50 bulb + $5.40 energy bill
Year 4 = $50 bulb + $5.40 energy bill
Year 5 = $50 bulb + $5.40 energy bill
Year 6 = $50 bulb + $5.40 energy bill
Year 7 = $50 bulb + $5.40 energy bill
Year 8 = $50 bulb + $5.40 energy bill
Year 9 = $50 bulb + $5.40 energy bill
Year 10 = $50 bulb + $5.40 energy bill
Kessil startup = $400
Year 1 = $3.24 energy bill
Year 2 = $3.24 energy bill
Year 3 = $3.24 energy bill
Year 4 = $3.24 energy bill
Year 5 = $3.24 energy bill
Year 6 = $3.24 energy bill
Year 7 = $3.24 energy bill
Year 8 = $3.24 energy bill
Year 9 = $3.24 energy bill
Year 10 = $3.24 energy bill
10 years of MH = $674.00
10 years of LED = $432.24