For purposes of sections 66-301 to 66-304:

(1) Covered electric generating unit means a fossil fuel-fired electric generating unit existing within the state prior to August 30, 2015, that is subject to regulation under the federal emission guidelines;

(2) Federal emission guidelines means any final rules, regulations, guidelines, or other requirements that the United States Environmental Protection Agency may adopt for regulating carbon dioxide emissions from covered electric generating units under section 111(d) of the federal Clean Air Act, 42 U.S.C. 7411(d);

(3) State means the State of Nebraska; and

(4) State plan means any plan to establish and enforce carbon dioxide emission control measures that the Department of Environment and Energy may adopt to implement the obligations of the state under the federal emission guidelines.