hi Steve,
in my observatory I use this equipment when I am at "full-speed" imaging:
http://www.stargazer-observatory.com/equipment.html
according to measuremwnts
the mount (tracking speed)
the CCD - it`s a Starlight X-press - surely the best solution for an observatory like mine, that is run by solar power. the SBIG cams are so hungry,...4-5 amps slolely!
the driver
the laptop
consumes some 4-5 amps
the most hungry guy is the laptop...
I also use 2 solar panles to charge a 88Ah car-accumulator, that provides everythng except the laptop with power.
for the laptop I use a smaller 33 Ah accumulator that needs to be charged every 3rd night I`m in the obs.
I start with a full laptop power and when this is "dry" I remove it after having plugged in the external powersupply.
BTW: I think I got one for You:
http://www.stargazer-observatory.com/sounds/stars.wav