BOSTON (CBS) – NStar is planning a power outage overnight for approximately 8,000 customers in the Back Bay who lost power after Tuesday’s transformer explosion. The outage is so the company can switch the customers from a temporary connection, to the company’s permanent underground network.

NStar says they are, “Proactively reaching out to all customers who will be affected by this outage to inform them of the restoration process and minimize disruption.”

The planned outage is scheduled to begin at approximately 3 a.m. Saturday morning and could last up to three hours.

The area that will be affected by the overnight outage are customers from Beacon Street to Boylston Street, between Kenmore Square and Copley Square.

Approximately 21,000 customers lost power after the explosion.