There is so much written about using fluorescent lighting in the garage, I guess there is something I'm missing. I completely understand that fluorescent's save energy, but if you look at the cost of purchase of the bulbs and fixtures, it would take many years for the average garage user to recoup the investment.
Not really.
Modern fluorescent lights are so much more efficient (on a lumens/watt basis) that they can nearly always offset their initial expense rather quickly, at least as compared to conventional incandescent bulbs.
I have a 850 sq. ft. garage and workshop. It's all going to be drywalled with fresh semi gloss white on the walls and ceilings, with light beige epoxy flooring going in. The cheapest 4' T8 fixtures I can find are about $20 each, with another $5 for a pair of bulbs. At $25 a fixture, I figure I will need about 25 fixtures, for a total cost of around $625.
So you're figuring on 50 F32T8 tubes, for a total of about 140,000 lumens (at the sources, with fresh tubes). That's quite a bit of light (~165 lumens/ft.^2, again based on SOURCE lumens); but in and of itself, that's OK. Hold that thought.
Instead I can buy simple keystone fixtures for incandescents bulbs for about $1.50 each, and another $1 each for bulbs. 25 of these fixtures will cost around $63, a savings of around $562.
But those 25 incandescent bulbs won't produce anything like the same amount of light as a similar number of F32T8 tubes. You didn't specify exactly which incandescent bulbs you expected to be able to buy for a buck each; but let's be generous and use these (at ~$1.25 each, if "bought right") as a typical example:
http://www.1000bulbs.com/product/110813/PHILIPS-139997.html
[Note that save for backlogged "stock on hand", these are now available ONLY from offshore, as all U.S. production halted more than two years ago. And they will surely only become more expensive as time goes on, due to the restricted availability. But let's set all that aside, for now.]
The rated output of this bulb is approximately 1,600 lumens, which is about typical for a 100W incandescent. It's rated life is just 750 hours; also typical.
So you will need nearly two of these (along with the additional fixtures and wiring to support them, of course) to replace each and every one of those F32T8 tubes. So, instead of 25 twin-tube fluorescent fixtures, you're now looking at installing nearly ONE HUNDRED of those cheap "keystone fixtures". But that's the least of it...
Check out any of the various representative tubes listed here:
http://www.1000bulbs.com/category/f32t8-fluorescent-tubes-5000k/
You'll find that their useful life is rated at anywhere from about 24,000 hours to over 40,000 hours. Many are rated at 30,000 hours; so lets use that as a nominal figure...
At just 750 hours of expected life, you will need to replace those incandescent bulbs
FORTY TIMES before the fluorescent tube presumably fails. So... $1.23 * 80 (remember, we need TWO incandescents to replace one fluorescent tube) = $98.40 (plus the future value of all that money you've got ******* in stockpiled bulbs, because you sure as Hell ought to buy ALL of those replacements NOW, while you can).
And that is STILL not the worst of it...
Over the course of just the FIRST pair of bulbs' projected life, they will consume approximately 150kWH of electricity. At, say, $0.12/kWH (a conservative estimate; adjust as needed for YOUR electrical costs), that's $18.00-worth of juice.
Meanwhile, our nominal 32-watt fluorescent tube, over that same period, has cost you just $2.88 to operate.
That's a difference of $15.12
per tube, or more than $750 total for the garage as a whole, after just 750 hours of operating time (which is less than a year, assuming an average of two hours per night)! It is literally more than a dollar an hour more expensive, for each and every hour you spend in the shop.
That'll pay for more than half of the cost of the epoxy floor.
On the contrary, those "bargain" fixtures/bulbs would cost you an additional $900-1,000 or so per year.
And we haven't even gotten to the part about how the QUALITY of the light is better from a properly implemented fluorescent installation. But seriously... Does this coffin REALLY need any more nails?
Now, for guys who are doing fine detail paint work in the garage, or who have the lights on for 15 hours a day, sure, the fluorescents and the technically perfect lighting distribution that they seemingly produce may make sense. However, for the average guy like me, working on odd house jobs or building and maintaining cars in the garage, I can't imagine incandescents in adequate numbers hindering my work. Additionally, if electric costs are a concern, the keystone fixtures can also be used with screw in fluorescent bulbs to save a watt. They make some high lumen output screw in fluorescents that use considerably less electric than a equivalent incandescent.
Hmmm... Apparently, more nails ARE needed.
Those high-output CFLs have been de-bunked previously (cf.
http://www.garagejournal.com/forum/showpost.php?p=3704005&postcount=26 and
http://www.garagejournal.com/forum/showpost.php?p=3705740&postcount=38); but in short: They are NEVER anywhere near as efficient as linear fluorescents; they ALWAYS cost more both to purchase and to operate; and being point-sources, they produce far less desirable coverage patterns (unless perhaps your ceilings are SO high that you really need high-output "High Bay" fixtures anyway). They beat conventional incandescent bulbs, of course; but as shown above, that's not saying much.
While the technical quality of the light either screw in alternative produces is likely not perfect,
I nominate this for "Understatement of the Week".
I'm sure that turning on 25 incandescent bulbs or screw in fluorescents will be akin to standing on the beach at noon on a clear July day.
That would depend almost entirely on how much space those 25 incandescent bulbs are trying to cover. In a small single-car garage, you'd have plenty of light (albeit, at a horrendous cost); in a 50'x100' pole barn, not so much.
Sometimes I think we just over think things, at some point, it's either bright enough to see what you're doing clearly or it's not.
It's not JUST about "brightness". There are many other factors which influence the quality of the lighting in any given workspace. But the basic cost/benefit projections are certainly easy enough to work out, if you just put a little thought into it.