CREATE TABLE table_57793 ("Driver" TEXT, "Constructor" TEXT, "Laps" FLOAT, "Time/Retired" TEXT, "Grid" FLOAT)

How many laps for a grid of over 18 and retired due to electrical failure?
SELECT SUM("Laps") FROM table_57793 WHERE "Grid" > '18' AND "Time/Retired" = 'electrical'
SELECT SUM("Laps") FROM "table_57793" WHERE "Grid" > '18' AND "Time/Retired" = 'electrical'