In addition, national infrastructure has been built in relation to inexpensive and generally abundant fossil fuels, responsible for most of the greenhouse gas emissions. Both countries have regions heavily dependent on fossil fuel production and processing. Other regions depend on importing energy from other provinces or countries or use hydropower to generate electricity. Energy regulation is primarily a provincial or state authority in both Canada and the United States. Environmental protection authorities are shared in both Länder by the Federal State and the Sub-Federal State.