Dave, The battery is of course used to power the starter for the car. Once started, the car draws power from it's "power source" This "power source" is the parallel combination of the battery and the alternator. Usually the alternator keeps up with power demand and it tries to keep the battery fully charged. If you need more power than the alternator can supply then you will be draining that power from the battery. Once started you could probably remove the battery and run the car on just the alternator, though this would not be a good idea because the battery acts as a regulator as well. Dave Delman D² & 6530 (minus the resistor) 8. Car's use of electricty / alternator & battery question Posted by: "daviddlasvegas" daviddlasvegas@xxxxxxxxx daviddlasvegas Date: Sat Jul 7, 2007 8:13 pm ((PDT)) Question about the DMC power usage... Is the battery used just to start the car; or Is the battery used all the time for power and then recharged by the alternator; or Is the battery used just to start the car and after start up, the car draws power directly from the alternator ignoring the battery? ************************************** See what's free at http://www.aol.com. [Non-text portions of this message have been removed] To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/dmcnews/join (Yahoo! ID required) <*> To change settings via email: mailto:dmcnews-digest@xxxxxxxxxxxxxxx mailto:dmcnews-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/