Let's see, 22 x 2,700 lumens = 59,400 lumens. That's the equivalent of almost SEVENTY ONE 60W bulbs. Now do you see why that's absolute overkill to the Nth degree? I still think that you'd have plenty of light with 4 fixtures in addition to the two which are already up there, and adding spot illumination where necessary.
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That is only 6 more tubes than in my shop of similar size and that certainly is not nay where near over kill, speaking from experience.
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Power used by 11 fixtures (bulbs + ballasts) would be about a horsepower and a half, 1100W all the time you're in the shop. Even fluor can get expensive to run if there's too much of it.
-------------------------------------------------------------------------------- BS! 22 bulbs only uses 704 watts. At 10 cents per kilowatt hour that is about 7 cents per hour or 56 cents per 8 hour day.