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[Clansgian AT wmconnect.com]

> >I don't really understand this technology.  The article doesn't give 
> enough info.  This is not a wind-up flashligh, nor does it use batteries.  
> It 
> lasts forever, without having to use and throw away a lifetime of 
> batteries. 

It uses a capacitor or bank of capacitors.  It does not have batteries and it 
last "forever" until the bulb or capacitor deteriorates with age.

Have you noticed that a radio or stereo will continue playing for a few 
seconds when you turn it off or unplug it.  You might even have noticed that 
if you 
turn a solid-state radio or stereo off while it is still plugged up, then 
unplug it, and turn it back on, it will sometimes play for a few seconds then 
go 
dead until you plug it back up.

In the "power supply", the circuit which converts the 120V AC into low 
voltage DC (which the device requires) employs one or more capacitors to 
"filter" 
the rectified AC.  

A capacitor is a very efficient electrical storage device and can maintain 
that storage for a very long time.  When I was doing electronics bench work 
(an 
exticnt occupation), I had two enourmous capacitors there about the size of a 
coffee can each, something like 22,000 mfd, and I'd charge them up from a 12v 
DC source and use them to power the transistor radio for nearly a month.

Capacitors charge instantly.  Even those huge coffee can capacitors took no 
more than 45 seconds to charge.

With the advent of low power, low voltage LEDs for flashlights, this 
capacitor based flashlight is quite feasible.  

Here's the bit.  This same principle crops up time and time again.  Do you 
have one of those LED flashlights that use batteries??  You can charge a 
NiMHd 
battery, AA or AAA, and that flashlight will keep a bright beam for months 
(used a few minutes a day).  The new technology that makes this flashlight 
feasible is not the improved capacitor, it's the LED bulb, which IS a turning 
point 
technology.  It won't be many years before that's all we use anywhere for 
lights.  Have you noticed those new traffic lights with LEDs,  many times 
more 
clear and visible.

So why not have a whole house full of capacitors to store your solar and wind 
generated electricity?   It's probably coming, but they are ghastly expensive 
compared to batteries and prone to failure.


James