Bill wrote:
How about getting rid of all those batteries in various devices in the home
and connecting the battery connections to one central battery?

That is to run separate wires when wiring a home and these would carry say
12 volts DC. There would be a central large battery and battery charger like
the type used in a computer UPS.

Then at each electronic gizmo which needs a battery, use a "battery
eliminator" along with a voltage regulator to supply it with the correct
voltage. And plug this into a nearby 12 volts DC "outlet".

This could provide battery power to smoke detectors, carbon monoxide
detectors, HVAC thermostat, security system, clocks, digital thermometers,
computer UPS, phone answering machine, etc.

Then only ONE battery to worry about...

A 9 volt battery eliminator picture...
http://www.wirelessmicrocolorcam.com... 7a77410624ea



My suggestion would be for a 48 volt DC system. Plain
old telephone service uses 48 volts DC for battery and
PoE, power over Ethernet is usually 48 volts DC. The
wire size could be smaller than that for a lower voltage
system and the 78xx type regulators are very inexpensive
and come in a variety of wattage ratings for stepping
down the voltages. The technology to pull it off is not
exotic and can be done with all off the shelf parts.
Solar and wind power could integrate quite easily with
such a system.

TDD