A solar power harvesting system comprising: a sunlight concentrating system for generating concentrated sunlight; a solar thermophotovoltaic converter including: metamaterial emitter including a box-like enclosure at least partially formed by a peripheral wall, said peripheral wall defining an interior cavity of said box-like enclosure and an inlet opening of said interior cavity, and at least one first bull's eye structure disposed on an outward-facing surface of the peripheral wall, wherein said box-like enclosure is fixedly disposed relative to said sunlight concentrating means such that the concentrated sunlight is arranged to be directed through the inlet opening into the interior cavity, and wherein said at least one bull's eye structure includes a plurality of first concentric circular ridge structures disposed in an associated fixed grating period such that a radiant energy beam is arranged to be emitted from said at least one bull's eye structure having a peak emission wavelength that roughly equal to said fixed grating period, and at least one photovoltaic cell fixedly disposed adjacent to the metamaterial emitter such that said at least one PV cell is positioned to receive said radiant energy beam emitted from said at least one bull's eye structure, wherein said at least one PV cell includes means for converting said radiant energy beam into primary electrical energy; and a thermal power system including means for receiving unconverted thermal energy passed from the interior cavity of the box-like enclosure, and for converting said unconverted thermal energy into secondary electric power. a sunlight concentrating system for generating concentrated sunlight; a solar thermophotovoltaic converter including: metamaterial emitter including a box-like enclosure at least partially formed by a peripheral wall, said peripheral wall defining an interior cavity of said box-like enclosure and an inlet opening of said interior cavity, and at least one first bull's eye structure disposed on an outward-facing surface of the peripheral wall, wherein said box-like enclosure is fixedly disposed relative to said sunlight concentrating means such that the concentrated sunlight is arranged to be directed through the inlet opening into the interior cavity, and wherein said at least one bull's eye structure includes a plurality of first concentric circular ridge structures disposed in an associated fixed grating period such that a radiant energy beam is arranged to be emitted from said at least one bull's eye structure having a peak emission wavelength that roughly equal to said fixed grating period, and at least one photovoltaic cell fixedly disposed adjacent to the metamaterial emitter such that said at least one PV cell is positioned to receive said radiant energy beam emitted from said at least one bull's eye structure, wherein said at least one PV cell includes means for converting said radiant energy beam into primary electrical energy; and a thermal power system including means for receiving unconverted thermal energy passed from the interior cavity of the box-like enclosure, and for converting said unconverted thermal energy into secondary electric power. metamaterial emitter including a box-like enclosure at least partially formed by a peripheral wall, said peripheral wall defining an interior cavity of said box-like enclosure and an inlet opening of said interior cavity, and at least one first bull's eye structure disposed on an outward-facing surface of the peripheral wall, wherein said box-like enclosure is fixedly disposed relative to said sunlight concentrating means such that the concentrated sunlight is arranged to be directed through the inlet opening into the interior cavity, and wherein said at least one bull's eye structure includes a plurality of first concentric circular ridge structures disposed in an associated fixed grating period such that a radiant energy beam is arranged to be emitted from said at least one bull's eye structure having a peak emission wavelength that roughly equal to said fixed grating period, and at least one photovoltaic cell fixedly disposed adjacent to the metamaterial emitter such that said at least one PV cell is positioned to receive said radiant energy beam emitted from said at least one bull's eye structure, wherein said at least one PV cell includes means for converting said radiant energy beam into primary electrical energy; and a thermal power system including means for receiving unconverted thermal energy passed from the interior cavity of the box-like enclosure, and for converting said unconverted thermal energy into secondary electric power.