A thermionic energy conversion system, preferably including one or more electron collectors, interfacial layers, encapsulation, and/or electron emitters. A method for manufacturing the thermionic energy conversion system. A method of operation for a thermionic energy conversion system, preferably including receiving power, emitting electrons, and receiving the emitted electrons, and optionally including convectively transferring heat.

A modified Nuclear Thermionic Avalanche Cell (NTAC) to reduce back-scatter losses of avalanche electrons emitted by a NTAC. The present invention provides a novel topological surface configuration for electron collector layers in NTAC devices. Sawtooth configurations of the surface configurations of electron collector layers allow for the recapture of back-scattered electrons, increasing the efficiency of NTAC devices as well as reducing thermal loading and increasing NTAC efficiency.

Systems, methods, and devices of the various embodiments may provide a portable power system for powering small devices that may be small, may be compact, may provide continuous power, and may be lightweight enough for an astronaut to carry. Various embodiments may provide a compact, thermionic-based cell that provides increased energy density and that more efficiently uses a heat source, such as a Pu-238 heat source. Nanometer scale emitters, spaced tightly together, in various embodiments convert a larger amount of heat into usable electricity than in current thermoelectric technology. The emitters of the various embodiments may be formed from various materials, such as copper (Cu), silicon (Si), silicon-germanium (SiGe), and lanthanides. Various embodiments may be added to regenerative thermionic cells with multiple layers to enhance the energy conversion efficiency of the regenerative thermionic cells.

A triboluminescence isotope battery can include a housing defining a chamber, and one or more energy conversion devices. Each energy conversion device can include a holder, a cantilever beam, a triboluminescence component, a first photoelectric conversion component, a radioactive source, a first charge collecting component, a second charge collecting, a first thermoelectric conversion component, and a heat dissipation component.

Various disclosed embodiments include elements for mitigating electron reflection in a vacuum electronic device, vacuum electronic devices that incorporate elements for mitigating electron reflection, and methods of fabricating elements for reducing reflection of electrons off an electrode. An illustrative electrode assembly includes an electrode. Elements are configured to reduce reflection of electrons off the electrode.

The present disclosure is directed to nuclear thermionic avalanche cell (NTAC) systems and related methods of generating energy from captured high energy photons. Huge numbers of electrons in the intra-band of atom can be liberated through bound-to-free transition when coupled with high energy photons. If a power conversion process effectively utilizes these liberated electrons in an avalanche form through a power conversion circuit, the power output will be drastically increased. The power density of a system can be multiplied by the rate of high energy photon absorption. The present disclosure describes a system and methods built with multilayers of nuclear thermionic avalanche cells for the generation of energy. The multilayer structure of NTAC devices offers effective recoverable means to capture and harness the energy of gamma photons for useful purposes such as power systems for deep space exploration.

A method for generating electricity includes generating electricity at a first reactor with a nuclear fuel element and removing the nuclear fuel element from the first reactor. The method also includes providing the nuclear fuel element at a second reactor and generating electricity at the second reactor with the nuclear fuel element.

Various disclosed embodiments include combined heating and power modules and combined heat and power devices. In an illustrative embodiment, a combined heat and power device includes a heating system including: at least one burner; at least one igniter configured to ignite the at least one burner; a fluid motivator assembly including an electrically powered prime mover; and a heat exchanger fluidly couplable to the fluid motivator assembly. At least one thermionic energy converter has a hot shell and a cold shell, the hot shell being thermally couplable to the at least one burner, the cold shell being thermally couplable to the heat exchanger.

Various disclosed embodiments include combined heating and power modules and combined heat and power devices. In an illustrative embodiment, a combined heat and power device includes a heating system including: at least one burner; at least one igniter configured to ignite the at least one burner; a fluid motivator assembly including an electrically powered prime mover; and a heat exchanger fluidly couplable to the fluid motivator assembly. At least one thermionic energy converter has a hot shell and a cold shell, the hot shell being thermally couplable to the at least one burner, the cold shell being thermally couplable to the heat exchanger.

A triboluminescence isotope battery can include a housing defining a chamber, and one or more energy conversion devices. Each energy conversion device can include a holder, a cantilever beam, a triboluminescence component, a first photoelectric conversion component, a radioactive source, a first charge collecting component, a second charge collecting, a first thermoelectric conversion component, and a heat dissipation component.