The direct energy conversion of nuclear energy requires nano-structured nuclear fuel. The principle of the radiation energy direct conversion is the usage of the knock-on electrons produced by the moving particle interaction with the lattice. These electrons transfer their energy to other electrons creating a shower of low energy and high current. A structure created of independent nanowires of two different materials insulated in a thin dielectric coating may use as electron showers energy harvesting device. The dimensions of the conductors are in the range of few tens of nm while the insulators are of several nm, offering a breakdown voltage of few miliVolts. When the mowing particles interacts with them it generates consistent e-showers when riches the high electron density conductor which are passing through insulators and stops in the low electron density conductor polarizing it negatively. These two types of conductors are connected to an external load transferring the accumulated charge. To obtain a higher voltage, in a uniform radiation field bimetal nanobeads insulated together and self organizing have to be cr4eated around the radiation source. The advantages consist in transforming the actual nuclear reactors into high power solid-state batteries with no heat exchangers and turbines.