If this rate persists, the United States will double to over half a billion by the middle of the next century. Already the Census Bureau is projecting an additional 70 million residents in the next 25 years, the equivalent of adding the 200 largest American cities yet again to the existing population. And our population has enormous environmental impacts. Whether it is air pollution in the cities or sprawl in the suburbs, farmland conversion in the valleys or deforestation in the mountains, Americans are destroying the natural systems that keep us alive physically and spiritually. There are many indicators of environmental impact, but energy use is the most thoroughly studied.
Energy use causes damage at all stages of production.
Fossil fuels require exploration, drilling, mining, transport, refining, burning, and waste disposal, which all create massive impacts. Impoundment of reservoirs behind huge dams floods natural valleys and canyons and disrupts riverine systems downstream. Even renewable energy is not without its consequences. Energy is the leading cause of global environmental effects such as climate change, oil added to the oceans, and acid rain. Energy use also is responsible for most local air pollution such as smog and particulates.