Energy Secretary James R. Schlesinger Jr. has ordered the Department of Energy's 19,000 employes to set a national example by cutting their energy use by as much as 10 percent by the end of the year.

Some DOE bureaucrats, however, are quietly grousing about another conservation measure that is being discussed in the department's head-quarters in the Forrestal Building: cutbacks in one of Washington's most prized perquisites, free parking.

Perhaps coincidentally, Thursday's Washington Post carried an editorial cartoon by Herblock depicting a scowling Schlesinger, with his ever-present pipe, surrounded by symbols of government energy waste. The secretary issued his save-more edict the same day.

Over the last year DOE has reduced its energy consumption by 10 percent to its current level of about 90 million barrels a year. Schlesinger told DOE field offices that he expects the department to reduce its gasoline use in vehicles by 10 percent and other energy consumption by another 5 percent by the end of the year.

"The DOE is going to set an example for the rest of the government," one department spokesman said yesterday. As for the possible cuts in commuter parking for DOE employes, the spokesman said, "It is definitely under consideration."