The actual wattage (power) being dissipated matters, not the 'equivalent wattage of the light produced.'

To answer your question: 40w.

That's kinda large for a CFL.

A 40 watt incandescent rated recessed fixture over the shower seems a little low and may not produce much illumination.

Using a CFL can bring up the illumination, while staying under the wattage rating of the fixture, but you can expect a shortened life out of the CFL.

Most CFLs are designed to be used in the upright position, unless otherwise noted, which when used downwards can overheat the internal electronics leading to early failure. Also an enclosed can only compounds the temperature problem.

An ideal solution would have been a recessed LED fixture. Even Home Depot has their EcoSmart line that uses Cree LEDs.

You could use an LED replacement bulb for recessed downward installation, or then it may be more economical to simply replace the CFL once every year or two. A 23 watt CFL - equivalent to a 100 watt incandescent - would be quite bright.

yousemitebill:

You said :"Most CFLs are designed to be used in the upright position, unless otherwise noted, which when used downwards can overheat the internal electronics leading to early failure. Also an enclosed can only compounds the temperature problem."

For a $10 bulb that's likely on much less than an hour per day, let's shorten the life by 50%. You're concerned then that the useful life is 10 years instead of 20 years?

I've got plenty of CFLs upside down, in enclosed fixtures, that are still going strong after 10 years. My experience would say it's nothing to be concerned about.

I've got plenty of CFLs upside down, in enclosed fixtures, that are still going strong after 10 years. My experience would say it's nothing to be concerned about.

I would suspect that the CFLs produced 10 years ago were of better quality than the ones produced today. We have a enclosed porch fixture with a CFL mounted horizontally and it's on from dusk to dawn every day of the year. It's been going to 5 years now which is pretty amazing if you ask me.

I have similar situations in closets where a 40W bulb in the can was a joke. I have a 100w equivalent cfl in the can with a lens cover over it. It lasted 5 years before I hade to replace it. The downside...takes 30 seconds to get to max intensity...still even at start up it was brighter than the watt incandescent.

"I would suspect that the CFLs produced 10 years ago were of better quality than the ones produced today. "

Really? What makes you think so?

My impression is the opposite, they seem much better today. The manufacturers have gotten a handle on spectrum colors (remember when they were all bluish?), instant-on intensity, etc. But my impression is only anecdotal as a consumer, I have no technical knowledge.

Putting CFLs in closets (or, over a shower as the OP said) and other places where the on-cycle is short seems silly to me. How much electricity can be saved with something that's used 10 minutes a day?

The OP wants maximum light while staying within the fixture's 40W limit. A CFL would help. Saving electricity has nothing to do with it.

Be careful when going overboard trying large CFLs there. Once you get to 20W or so, they're bigger than a standard bulb and may no longer fit in the enclosure.

Also, you need to check if the CFL you are purchasing is rated for wet conditions.

you could also remove the $10 flat trim and install a $25 Halo drop trim which is rated for 60 watts and also brings the lamp down out of the can a bit and is MUCH better at lighting an area.

CFLs now are probably poorer quality because they're much cheaper. I've experienced a very high failure rate, unlike the first few I bought which were expensive but lasted very well.

Given the energy cost to manufacture items that keep breaking down, LEDs or incandescent seems to make more sense, unless the name-brand cfls are ok. I'd go with LED personally, the new ones give off a very clean light in the colour temperature range we expect to see.

I only buy name brand CFLs. I've found the durability and quality to be consistently high, I can't remember the last time I had a dud (I know I've had no problems in the last 5 years).

To the contrary, I think LEDs are very promising but not ready for prime time. The ones available now are expensive and not very bright yet. As volumes increase and the technology improves to make available lots of choices at and above 1000 lumens, it will be different. For now, who needs an expensive and dim bulb with a 25K hour life? Maybe a few for outside lighting that you can leave on inexpensively, but otherwise?

"Also, you need to check if the CFL you are purchasing is rated for wet conditions."

As long as there is a cover over the fixture it is damp, not wet.