If you want 24/7 access yes. I see mention of leaving the machine on all the time. Here's the numbers off of my laptop.
11.1 volts * 4.05 amps / hour = 44.995 Watts/hour * 24 hours/day = 1078.92 watss/day = 1.07892 KW/hours * $0.10 per KW/hour = 10.7892 cents / day to run.
Bookmarks