Oregon DMV 2005 Vehicle Code Book

While it is hard to narrow down specific requirements because of things like the law stating that a standard must be made (but not what such standard is) there are specific comments about EV.

Page 23 of Chapter 815 (Vehicle Equipment Generally) says in 815.300#9 that EV are exempt from the pollution control system requirements.

I did find some more information in Chapter L. Vehicle Types:

Passenger vehicles are titled using the VIN from the frame (or an MCO if it is a New Passenger Vehicle).

Electric vehicles are registered as per ORS 803.420
(looking that up, it is $27/yr)

Electric vehicles are subject to residency/domicile, financial responsibility, and odometer requirements. If a vehicle is manufactured without an odometer, the Exemption from Odometer Reading Requirements, Form 735-6745, must be completed. Electric vehicles are exempt from DEQ requirements (ORS 815.300)