Example embodiments are directed to systems and methods for denying power to unauthorized power loads within a spherical waveguide bounded by the Earth's surface. One or more eigenmodes of the Earth-ionosphere waveguide may be computed based on a mathematical model incorporating electrical properties of the terrestrial surface and plasma physics of the ionosphere. A phased array of wave guide couplers, each including an array of electrically-connected waveguide-coupling elements, may be configured at different geographic locations for coupling to the one or more eigenmodes and generating standing waves in the Earth-ionosphere waveguide. Power loads may be detected via power reflections, and power nodes and nulls of the standing waves may be steered with respect to specified locations by adjusting relative phases and/or amplitudes of the waveguide couplers. Locations of power loads may be triangulating reflections. Power nulls of the standing waves may be steered to locations of unauthorized power loads.