If a lease has been signed but the apartment is blocked from receiving power by the utility company, can the lease be broken?

In every lease there is an implied warranty of habitability which requires the landlord to maintain the premises in a habitable condition by complying with local and state housing codes.  Not having electricity is clearly a breach of the implied warranty of habitability  When there is a breach of the implied warranty of habitability, the tenant notifies the landlord as you have done and the landlord is required to respond within a reasonable time by making the necessary repairs.  When the landlord fails to respond within a reasonable time and correct the problem by having the electricity restored in your case, the tenant has the following options for a breach of the implied warranty of habitability:  The tenant can make the repairs and deduct the cost from the rent which is impractical in your case or the tenant can move out and terminate the obligation to pay rent for the balance of the term of the lease or if the tenant stays on the premises, the tenant can withhold rent and defend against eviction.  Another alternative is to sue the landlord for breach of the implied warranty of habitability.