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_name_17 ( gross_capacity VARCHAR, commercial_operation VARCHAR )

### Question ###
What is the gross capacity of the unit that started commercial operation on August 28, 1987?

### Accurate SQL ###

SELECT gross_capacity FROM table_name_17 WHERE commercial_operation = "august 28, 1987"