Circuit Breaker Box Addition?

Yes you can, as long as you do not exceed capacity of the 100amps. From your user name, I suggest you hire a licensed electrician, and he could probably switch out your fuse box, and give you a few extra circuits for under $500. If you need more power, the electrician could get you more amps. Call an electrician and get an estimate. Let them get all the supplies. They can usually get higher quality equipment that you can.  more