Calories per hour to horsepower (metric) conversion calculator shown above calculates how many horsepower (metric) are in 'X' calories per hour (where 'X' is the number of calories per hour to convert to horsepower (metric)). In order to convert a value from calories per hour to horsepower (metric) (from cal/h to hp) type the number of cal/h to be converted to hp and then click on the 'convert' button.