In many states, landlord is responsible for making the unit inhabitable. If extended outage for heat, electricity, gas and/or water causes the unit to be inhabitable, here is his options
(1) stop paying rent and live in the house without utility service until the outage is over.
(2) terminate lease and move out, and you have to refund deposit.
(3) landlord providing temporary electricity, heat, gas and/or water and he continues to pay rent.
This is at least true for CA and NY. I cannot guarantee for any other states.
Also check your landlord policy to see if they cover lost rent in such situation.