[Shop-talk] CFC Bulb Failure

[Randall]

> How long until lighting circuits a all low voltage DC 
> circuits?  

Probably never, is my guess.  It would be a huge hassle to switch, and the advantages would be minimal at best.  CFLs need fairly
high voltage and smart controllers, and are already starting to be pushed out by LEDs.  The LEDs need even fancier controllers (for
good efficiency and life), and running from a DC bus would make the controller only marginally simpler.  

As it happens, I'm in the middle of building some LED lights for my antique car, to run from roughly 12v DC (actually anywhere from
11v to 14v).  Roughly half of the input power (depending somewhat on voltage of course) gets wasted in my simple controller to keep
from burning up the LEDs and still run them close to their design limit.  To get better efficiency, I would have to go to a DC-DC
converter.

On the downside, low voltage means more power lost in the wires (unless you make the wires bigger, which gets expensive), and
somewhere there still has to be a power supply creating the low voltage DC from the mains power.  And there would be a lot more
potential for confusion, not to mention bad effects if someone connected the wrong things together.  Portable lighting (lamps) would
be a problem, too.

Of course, I'm sure there are a few folks around already doing the DC thing; running from batteries charged from their solar panels
or motorhome engine.  But not many.

Randall