Nearly all solar oven designs operate at peak performance only when directly facing the sun. The single critical shortcoming in the solar oven marketplace is the lack of an apparatus which will rotate your oven so that it always faces the sun and optimal performance is sustained for the entire cooking time. Unless you are at home all day with nothing else to do, the necessity to manually rotate the oven is a significant inconvenience - no 'Set It and Forget It'. Zhu and Kim have offered a mere 18 calculations to use in order to find that correct angle: