CREATE TABLE table_15561 ("Unit" TEXT, "Type" TEXT, "Net Power" TEXT, "Total Power" TEXT, "Finish construction" TEXT)

Which type had the unit greifswald - 7 (kgr 7) ?
SELECT "Type" FROM table_15561 WHERE "Unit" = 'greifswald - 7 (kgr 7)'
SELECT "Type" FROM "table_15561" WHERE "Unit" = 'greifswald - 7 (kgr 7)'