Although a cleaner choice than oil and coal-fired electricity production, natural gas isn’t considered renewable energy, as we’ve already pointed out. It takes millennia for organic material to become natural gas. Natural gas produces 0.92 pounds of carbon dioxide per kilowatt-hour, according to the U.S. Energy Information Administration (EIA). So for every 1,000 watts of electricity you consume, just under a pound of CO2 was emitted during energy production.