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_56498 ( "Wind farm" text, "Capacity (MW)" real, "Country" text, "State/Province" text, "Notes" text )

### Question ###
What is the total capacity (MW) of the farm that is noted as being under construction?

### Accurate SQL ###

SELECT COUNT("Capacity (MW)") FROM table_56498 WHERE "Notes" = 'under construction'