Hey Frank,
What's up with your alternator? Maybe some of the alternator gurus here can offer some advice. That being said, it's possible it can be rebuilt at a good shop for a lot less money, otherwise you should be able to drop in one from another manufacturer like Balmar. It can't be too high amp though, you'll use most of the engine's hp to drive it!
I'm sure your aware but on the Renault control panel there is a switch to "turn off" the charging, if you are finding that the alternator isn't charging it may be that switch or wiring. I've noticed on mine if I switch it back and forth a few times while giving the engine some revs the alternator will kick on.
Manny