Ouch
Yea it draws 3/4 to 1 amp at 14.5 volts. That is 11-14 watts. It kind of sucks to use all that electricity to just hold the battery contactor.
I looked into 5 ways to eliminate this device or replace it, but bottom line it is cheap, works and is pretty fail safe. You can upgrade to a kilovac $150 magnetic semi-latching heavy duty relay, which only uses milliamps to remain close, but not sure it's worth it. Just the nature of the beast.