On 19 Sep 2003 17:36:21 -0700, (Rob Patrick) wrote in
message :

I've had a pretty rough year for electricity at my house. Seems like
after every rain shower, someting elecronic stopped working. In
addition, about once a month, power flicks off just long enought to
set every piece of gear with a clock a-blinking. After hurricane
Isabel knocked out my power for 15 hours, I've decided to finally look
for a whole-house backup system.

To take care of the momentary outages and brownouts, a huge
battery-type UPS that was connected to the whole house would be ideal
(it seems.) There is actually a company (Banner Electric -
www.bannerbackup.com) that makes such a system and actually markets it
as replacements to generators - but I'm not sure exactly how long they
would keep a house running (even with loads minimized) plus there is
reference to a system costing $20,000 on their web site (ouch...)

I'd like to get the thoughts of anyone out there about the wisdom of
connecting the whole house to a big UPS. It seems to me like the ideal
system would have an automatic generator for extended outages but a
battery to handle short outages and to keep power flowing while the
generator started.

Rather than connecting the entire house to yet another monolithic system
that may create yet another single point of vulnerability, consider a
carefully designed, _distributed_ backup system.

Consider each power need separately and creatively. For example, it is much
less expensive to replace an electric range/stove with a natural gas or LP
range/stove than to provide battery backed UPS for an electric range/stove
as you seem to be entertaining.

One part of that system could consist in a DC power network for devices
that intrinsically run on DC and have AC-DC converters built such as
computers.

I have set for myself the goal of an independent 48vdc whole-house wiring
system, using an off-the-grid supply with battery and 120VAC "backup", to
power the ever-growing number of PC's, SBC, subsystems, and other HA
accoutrements.

The motivation stems partly by the need to improve the grounding system for
these devices so that they don't fail during lightning events, and partly
out of embarrassment of how little truly _necessary_ function these devices
provide for the amount of electrical energy and other resources they
consume ...

There are many sources of 12vdc- 24vdc- and 48vdc-input ATX-style supplies
for computers.

http://www.icpamerica.com/power.php
http://www.aristaipc.com/others.htm
http://en.ieiworld.com/products/inde...WER% 20SUPPLY
http://www.amtrade.com/pc_power/swit...ies_lg_pix.htm
http://www.kontron.com/techlib/whitepapers/5007.pdf
http://www.boser.com.tw/products/power/bpw830v.htm
http://www.magtechind.com/__DC___DC_...converter.html

to name a few

HTH .. Marc

www.ECOntrol.org