Our design is not original but is open source, as are all our machines.
Before embarking on making a UV water sterilizer read the following Philips Lighting brochure about germicidal lamps: visit the Philips Lighting site, then search for the “PHI5998 UV Purification Tech Upd.qxd” document.
The UV lamp (bulb) we use is a USHIO G8T5 available for $8 from Atlanta Light Bulbs.
The fixture was from Home Depot. Take the bulb with you when you shop for a fixture. It is a mini bi-pin and measures 11 3/8″ not including the two pins on each side with a 5/8″ diameter.
Fluorescent lamps, UV lamps and compact fluorescent lamps all work on DC as well as AC. The positive DC voltage from the bike generator is brought in on the common prong. This is the larger prong of the fixture plug or the white wire of the fixture.