Energy, IL has a population of 1,166 and is the 14,203rd largest city in the United States. The population density is 991 per sq mi which is 346% higher than the Illinois average and 994% higher than the national average. The median age in Energy is 53 which is approximately 41% higher than the Illinois average of 37. In Energy, 64% of the population over 15 years of age are married, 98% speak English and 1% speak Spanish. 80% of Energy residents were born in Illinois, 18% were born out of state, 1% were born outside of the United States and 1% were foreign born.