Thursday, July 31, 2008

LED Bulbs

A variety of people are claiming that LED lights are going to be the next big thing in lighting. Well, if their efficiency is as planned, I sure hope so, but I think a bit of caution is in order here.

For example, the standard lightbulb in our country, the 60W, produces about 1100 lumens. Here's a link to an 1100 lumen LED bulb. Notice anything?

Yeah, it's $54 plus shipping and handling, and it works off 12V DC instead of 110V AC. In other words, the user must provide a power supply (say $10), integrate it in to house wiring ($100 if you're not an electrician), and then you're good to go.

So when does it pay for itself? Well, given that you can get a 60W equivalent CF bulb for $2 or so, never if you don't break the CF bulbs and require cleanup. If you're comparing to incandescents, after 12000 to 32000 hours if you don't count the opportunity cost, never if you do.

In other words, these things need to come down in price by about a factor of five before they're cost effective. Oh, and by the way; I haven't even factored in the reality that power supplies don't last that long, either.

4 comments:

Orianna Laun said...

It makes me ask, "WWJD?" That would be "What Would Joe Do?" I don't know if you like/listen to Garage Logic, but I have a feeling an overpriced lightbulb is something up with which he (nor I) will not put.

Bike Bubba said...

Well, we're also left with the Proverbs 31 wife and Lydia (of Acts) wearing tapestries and purple. So we have to very carefully define "overpriced" to avoid the problem of deliberately buying "cheap" when it's actually better to buy "well."

There is also the little issue of Jesus' seamless garment. That wasn't a "Chevy" item at the time, but really more of a "Buick" or "Olds" quality, if you remember the old way of describing things.

Unknown said...

Realize the price of LEDs has been falling though. Plus it looks a little like it could be a classic case of the price would be lower if they were made in higher quantity, but they need the price to come down before they can sell enough. I do wonder about the light quality. I have a couple LED flashlights, and I like them, but the light is a little harsh. I understand there are things that can be down to mitigate this, but I not really up on that to know how well it works.

The 12 volt power requirement wouldn’t be a concern to be though. Realize that CFL’s already have an integrated electronic ballast in them, so I think you could do something pretty similar with a “LED light bulb.” They can make some pretty small switching power supplies these days for not very much.

I do wonder though, with the explosion of wall warts, and potentially low voltage lighting, how long is it before it makes sense of have a distributed low voltage power system in out homes?

Bike Bubba said...

Daniel--true, it's falling (new technologies always do), and I'll be glad to let the "early adopters" (those who buy 'cause it's "new") help manufacturers iron out the warts in the technology.

Regarding a low voltage system, you might do well with about 45V DC--it would be a nice nonlethal voltage that you could have in your home. You would find, though that you'd have to be running a AC/DC converter in your home with fairly substantial amperage--one that would plunge you into darkness if it failed.

I'm not quite sure that I'd go for that, knowing what I do (I've worked in this area) about the reliability of consumer electronics.