Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_14315 ( "Reactor Unit" text, "Type" text, "Average Output" text, "Rated Power" text, "Began construction" text, "Finish construction" text, "Commercial operation" text, "Close of reactor" text )

### Question ###
What is the rated power for the reactor that ended construction on May 10, 1978?

### Accurate SQL ###

SELECT "Rated Power" FROM table_14315 WHERE "Finish construction" = 'may 10, 1978'