There is a new offering from the RDD guys in Redmond.  Besides their
de-ice system (hot stuff!) they are selling also a dual bus alternative
(snip below from their Web site: Electri-X(tm) by RDD

Electri-X is an advanced electrical system specifically developed for
the unique demands of the experimental aircraft builder. Electri-X
consists of two independent systems that are redundant in every aspect.
The critical difference between dual and redundant is that many aircraft
with dual electrical systems generally have a lesser back-up electric
system that cannot operate all standard systems. Electri-X redundancy
means that both electrical systems are equal in form and function-
meaning that either system is fully capable of powering all standard
equipment independently.

Electri-X by RDD offers a level of electrical power delivery redundancy
usually only found on twin-engine or very high-end piston singles. Dual
60 amp alternators, dual 15 amp hour batteries, dual busses and dual
wiring harnesses ensure that an electrical emergency will not force you
to shed power, pull breakers, turn off critical standard systems or fly
a partial panel in the event of an electrical emergency. Web site: http://www.rddent.com/products.html E-mail to: david.mcrae@rddent.com

Just another option.  -----Original Message-----
From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of
Dan Ballin
Sent: Tuesday, March 27, 2007 12:56 PM
Subject: [LML] Essential Bus??
I am (like a lot of us) doing a dual alt/dual battery system.  70 amp
alt as a main with a 20 amp alt as an Aux.