It started with a simple question by Samuel W. Bodman, the energy secretary: “What does the future hold for oil and natural gas supply?”

The query was made in October 2005 in a one-page letter sent to Lee Raymond, the former chairman of Exxon Mobil and head of the National Petroleum Council, a federal advisory group representing the oil industry.

After nearly two years, Mr. Raymond has finally delivered his answer.

The result is a colossal 476-page study entitled “Facing the Hard Truths About Energy” that involved 350 participants, suggestions from over 1,000 people, submissions by 19 foreign governments from Australia to Saudi Arabia, and dozens of subcommittees.