From: John De Armond
Subject: Re: strategy for saving power on pool pump use
Date: Sat, 07 Apr 2007 13:52:33 -0400
On Sat, 7 Apr 2007 09:06:35 -0700, "Ulysses"
>"Epictitus" <mikeNOSPAMster.firstname.lastname@example.org> wrote in message
>> care to share any links? I'd like to check out how you built it.
>I don't have a web site for it. Basically it was made from an ignition coil
>for a car to produce an arc that produced ozone. I made a power supply
>using a transformer to supply the 12 volts for the coil and a pulse circuit
>built on a 555 timer to pulse the DC. The components were housed in such a
>way that the air would flow through the housing and past the arc via a
>venturi connected to the pump outlet.
>Unfortunately I came up with what may be a new component that may be
>patentable so I'm not quite ready to share that yet. If I ever manage to do
>a patent search and either apply for a patent or not then I'll be happy to
>share it with those who just want to build one for themselves.
An arc is a poor ozone generator. The most efficient electrical
method is corona discharge. The other method is short wave UV.
Most commercial ozone generators for air employ a variation of a high
potential difference across a glass insulator. One electrode inside a
glass tube or bottle and one on the outside. Here's a friend of
mine's site showing how to build two different types of corona
For a pool, air could be pulled through such a device and
bubbled/sucked into the water. Ozone is much more soluble in water
than oxygen so it dissolves readily.
For water, the most usual method for ozone generation is a short wave
mercury UV lamp. This type of lamp has a quartz envelope that passes
the 253nm emission line of mercury. Longer wavelengths don't work.
Many UV lamps are designed to pass only longer wave lines and thus
won't make ozone. That's why Clive's mercury vapor arc tube didn't do
particularly well. The quartz formulation passes little short wave
UV, a safety measure in case the outer globe is broken.
I have an approx 4 ft long quartz envelope cold cathode UV lamp that
came out of a water sterilizer. It's worn out and its emission is
down enough that it no longer was adequate for sterilizing water but
it still makes enough ozone that when fired off, the air gets choking
with ozone in short order.
Though not nearly as intense, a germicidal lamp is another good ozone
generator, though some mfrs have been playing around with the glass
formulation to trim the shortest waves and cut down on airborne ozone.
These are the blue lights you see in barber shops. A source:
These are pretty reasonable prices as germicidal lamps go. Your local
barber and beauty supply probably also stocks them (the "Sally's"
chain does in this area) but they'll want more than $30 for a 2 ft
bulb. One trick I've learned is that at the expense of bulb life, one
can run a shorter bulb on a longer bulb ballast, say, a 24" bulb on a
48" ballast and get more UV production.
Making ozone in water with one of these can be as simple as soldering
wires to the pins, potting each end in RTV or epoxy and dropping the
weghted lamp into the water. In a return well if you fear the lamp
getting broken in the pool. Don't let any of the bulb be above water,
as the intense UV will turn white PVC yellow and brittle literally