The |heures filter displays the hours portion of the date to which it is applied.
[(#DATE|heures)]
The hour returned varies from 00 to 24.
If the date to which the filter is applied does not contain any time information, e.g. ([(#VAL{2009-10-24}|heures)]), the filter will simply return (zero).
See also the heures_minutes, |minutes and |secondes filters.