Final answer:
The largest consumers of energy per capita as of 2004 are North America, Europe, and Sub-Saharan Africa, considering factors such as geographical size, climate, and historical data on energy consumption.
Step-by-step explanation:
According to the information provided, the three continents that were the largest consumers of energy per capita as of 2004 are North America, Europe, and Sub-Saharan Africa. This conclusion is drawn from various references indicating that regions with large geographical extents, such as Russia, Canada, and the U.S., require more long-haul transportation and hence have higher energy uses. Furthermore, climate factors such as the need for heating in colder countries, which applies to Russia and Canada, drive up energy consumption. The U.S. historical energy consumption data reveals that Americans, with only 6% of the world's population at the time, used much more than ten times the global average of oil and gas, indicating a very high per capita consumption. Additionally, despite East Asia being the largest economy on a GDP basis, it drops to third on a per capita basis after Europe and Central Asia. Sub-Saharan Africa is highlighted, showing a contrasting scenario where economic outputs and energy usage patterns can differ significantly within a continent.