Lumens Watts Equivalency...
 

Here it is.


Best,

-AC

Here you go:

http://www.thelightbulb.co.uk/assets...mens-watts.gif

Covers most of the common residential bulbs.

Remember this: raw lumens doesn't tell the whole story. There are other things to worry about like color temperature/CRI, beam angle, power factor, etc. New lights aint old lights.

I'm a fan of led, however the power difference between led and cfl makes it hard for me to see the payback for the price jump. They are a great option for gu10 and mr16 halogen track lights and candelabra based tiny lights used in some ceiling fan 'up lights'.

If you Google "LED CFL payback", you will find all of the difficult work of payback calculations already done for you.

-AC

The thing I like best about cfl and led lights is not having to change bulbs every month. They both last forever compared to incandescents. And the durability factor is worth so much more than pocket change.

Cfl's will generally screw right in anywhere a general-purpose old-school bulb needs to be replaced. They do a good job at throwing light evenly in all directions, and not blinding you if you look straight at them. Installed in closets, pantries, and attics, they will literally last a lifetime. And guess what? No flash then dark next Christmas when you go to dig out all those ornaments.

LED lights come in way more shapes, colors, sizes, and configurations than cfl's do. I have replaced some of my 2 foot and 4 foot fluorescent fixtures with led strip lights with highly satisfying results. No more delay when the switch is flipped, and no more flickering when it's cold outside... I believe they have now graduated beyond the "Christmas lights" they used to be! Put a "corncob" in your droplight in the garage and repeatedly pick the thing up off the ground, still working. That corncob has saved me at least an hour of having to hunt for another bulb in the middle of a project.

Beware what color of white you get, though. There are many colors with "white" in the name, and even the same name is a different hue from brand to brand.

The math isn't difficult. My average cfl is 15w, I can get 2-3 for $10. The Led equivalent uses 13watts, cost about $20 per bulb. I'm not in a huge hurry to save 3 watts per hour of use. Maybe the technology will get more efficient of even cheaper. The payback on solar is even faster!

The math is more difficult than simple arithmetic... there's actually some multiplication and division involved.

When you talk about "payback", time is involved. To make an intelligent comparison, you need to look at bulb life, bulb cost, and energy use over the lifetime(s) of your alternatives.

There are web sites that have already done the analysis, and multiplication and division for you, so you only need to look at the answer.

Another aspect that you may or may not want to take responsibility for is the environmental cost of manufacture and disposal, because when you throw something away (especially mercury), there really isn't any 'away'.

Also, saying that solar has a quicker payback is a meaningless comparison partly because you haven't yet determined the payback for your light options, but even more because solar power and efficient lighting are two separate and unrelated classes of technology.

If you really want fast payback, get rid of your car(s).

-AC

Please AC, enlighten me on the pay back. I'm not sure how quickly the pay back on getting rid of my car would be, but it doesn't light my house very well from the driveway anyway. Why not take bad cfls for disposal at the hardware store? The break even point for switching from cfl to led can be 4-10 years, that's to break even against a $3 bulb.

If you only intended to live two or three more years, your analysis would be perfect.

You are comparing a bulb with a higher initial cost and a far longer life to a bulb that has a lower initial cost and a shorter life. Your comparison is over a shorter life.

Bad comparison.


By the way, I am getting LED bulbs for around $5.

-AC

Don't get offended or nothing, but are you a big fan of paper plates? I believe their break-even is almost immediate, what with no need to wash them and stuff.