Hi tired. As you know, I'm also in California. and understand that I'm a believer that you can never have too much light (you can always turn some off, but you can't turn on what isn't there). My kitchen measures about 17 x 13 (the kitchen part, not including the pantry or the family room) with 9 ft. ceilings (except for where the two halogen lights are -- they're in a light bridge that is 4' above the counter). We have 6 recessed 5" cfl cans (total wattage: 156), 1 large island pendant (total wattage: 240 incandescent), 2 recessed 4" halogens (total wattage: 100 halogen) over one prep area (this is the best light in the room), overcabinet fluorescent tubes (total wattage: about 130 fluorescent) and undercabinet fluorescent tubes (total wattage: about 100 fluorescent).

The only thing I would have done differently - I would prefer halogen downlighting over the island, but couldn't find a fixture I liked or that worked with the beams in our ceiling.

We also have very good natural light.

Wattage isn't all that useful in these situations. Instead, look for the lumen output of the bulbs. It looks like a 28w T5 bulb generates around 2900 lumens when new. Fluorescents gradually dim with age, so the bulbs may be down to 2000 lumens each by the time you replace them. Some of the light generated won't make it out of the fixture, so maybe that 2-bulb fixture could put as little as 3450 lumens into the room on a bad day. My guess (and I want to stress that it's a guess) is the 2-bulb fixture would seem pretty bright when the bulbs were new, and seem a little dim when they're older. It might be nice to have a 4-bulb fixture with the tubes switched in pairs so you can turn on two or four, as you like.

If you have a problem with this arrangement, it probably won't be in terms of sheer quantity of light; it will be with how it's distributed. It may be able to fill the room with light, but it won't be very good at lighting the counters around the perimeter of the room, especially when you're standing at the counter and your body is positioned between the central fixture and the counter where you're working, casting a shadow in just the wrong place. You'll need those cans or, even better, good undercabinet lighting.

For a kitchen this size I don't think shadows will be much of a problem with a central fluorescent. They radiate over a 4' length, for goodness sake. If shadows are a problem, using two fixtures will defeat them pretty well.

It never hurts to have undercabinet lights anyway.

From what I've seen, cans make things worse because they create their own strong shadows unless used in massive, electricity-wasting quantities.

David, my mom's got a 4' fluorescent fixture (albeit it's an old T12 model) in a smaller kitchen than the OP's and it does a poor job of lighting the counters. It's true that the shadows are much less distinct because the bulbs are so long, but there's still markedly less light wherever one works. Mom visits my kitchen, with its carefully placed incandescent cans, and is jealous of how well lit my counters are. I'm not saying cans are in any way ideal, but I think you sell them short.

Thank you for the replies. I was curious if there is a rule of thumb as to number of lumens per sf or # of CFLs per sf? What sf coverage would a 5" CFL give?