[plug] 8% reality tax

[Leon Brooks]

Bret Busby wrote:
> What, only 92%? What happened to the other 8%? Is this some GST thing?

It's reality creeping in around the edges. Entropy Tax. If you think
electronics are perfectly efficient, then I highly recommend setting up
a SPICE model as a critical piece of your future education.

92% is actually pretty good, in fact amazing if there's batteries
involved.

Those crappy little brick-sized UPSes that people plug PCs into to have
them fried can run down to as bad as 70% efficiency, but are typically
80-something%. An analog power supply (battery charger, plug pack for a
modem, those kinds of thing) can easily drop below 50% (you were
wondering why plugpacks run warm?) and a near-perfect one runs at about
65%.

Add to this the fact that your rechargeable batteries will lose energy
(actually, convert it to heat) on each transaction, and even lose a
little energy just from being charged, and 92% is better than I would
dare hope for in such a design.

-- 
Dogs have masters. Cats have staff.