I have a fluorescent fixture which is constantly running with an emergency ballast for backup. The fixture holds two 32W t8 bulbs and is an electronic ballast. Would anyone know how much this would cost to run every month or annually when running 24/7 ? Just trying not to have my electric bill so high. Thanks!!

I assume that 32W is HF-ballast power rating, i.e. the tubes actually use 32W whn powered by HF ballast. So, we have to add the ballast's own power consumption. It is fair enough to assume that with the ballast, the power would be about 36W for each tube

Together that is 72W

The emergency module (its charging transformer) draws another maybe 1..2 W

Together that is 74W

74W = 0.074kW

Running that for 1 hour takes 0.074kWh. With electricity cost of $ 0.15/kWh, that is 0.074kWh * $0.15 = $0.011. (Change according to your electricity rates)

Running for 24 hours : 24 * $0.011 = $0.26

Running for a month : 30 * $0.26 = $7.80

Running for a year : 365 * $0.26 = $94.90

Wow I thought it was going to cost a lot more phew. I really appreciate your time. Thank you so much Ash!