CREATE TABLE table_70711 ("Model" TEXT, "Specification" TEXT, "Build date" TEXT, "Total produced" FLOAT, "Wheel arrangement" TEXT, "Prime mover" TEXT, "Power output" TEXT)

Name the power output for model of s-13
SELECT "Power output" FROM table_70711 WHERE "Model" = 's-13'
SELECT "Power output" FROM "table_70711" WHERE "Model" = 's-13'