Unless you also live under that roof and will also be without power... you will not be allowed to turn it off. This is known as "self help eviction" and there are a TON of laws on the subject.
Tenancies can be ended with notice. Notice is **usually** based on the frequency of payment (if no lease to say otherwise)... therefore a weekly rent payment cycle = one week notice to quit.
make it your business to learn what the laws are down there. At the courthouse or better a LL ass'n. Above is a link to state laws. Read up.