Yet, if you consider where populations are growing fastest, they're not in the same countries consuming the most energy. For example, the United States has a population of just over 300 million people -- that's about 5 percent of the people on Earth. Yet we consume 20 percent of the world’s energy and cause 19 percent of the world’s greenhouse gases.
China’s a little better, but still skewed in the wrong direction with 20 percent of the world's population that is responsible for 33 percent of its greenhouse emissions. Developing nations like India and some African countries tend to consume much less energy but add to the population crisis. India, for example, is almost the exact opposite of the United States on an energy consumption scale, using only 5 percent of the world's energy. But with nearly 1.2 billion people, it's responsible for almost 17 percent of the Earth’s population.