Recurrent Nova Engine

A Recurrent Nova Engine or (RNE) is a megastructure that utilizes repeated artificial novae as a power source. Relying on regular relatively small amounts of mass dropped onto the white dwarf, a small fusion reaction is maintained on its surface. Occasionally, the white dwarf will begin a runaway fusion event, called a micronova, that releases a large amount of energy. This energy is then collected and stored.

The idea of using novae as a power source comes to almost every species just as the idea of Dyson Swarms does. Most species, however, simply never grow to control enough energy to even seriously consider the technology. Only the oldest civilizations can create them. Currently, they are used for the mass production of elements beyond iron that a fusion reaction would absorb energy for. Most Dyson swarms, incomplete as they are, fail to satisfy the large demand of civilizations for heavy elements. For most of history, heavy elements were simply harvested from moons or asteroids. Having this technology is a game-changer on the galactic stage.

Currently, there are only a handful of these objects in the universe. They are all publicly owned with companies renting out energy and space on the device to create rare isotopes or large quantities of transuranic elements at a far cheaper rate than around a star.

Design

The RNE is a large sphere mostly made up of power-harnessing devices. This sphere is the largest type of megastructure commonly built at over an astronomical unit across. In the center of this sphere is a white dwarf. Any white dwarf would work, although the white dwarves usually mass between 0.75 to 1.25 M_☉ are ideal. The highly energetic process creates an artificial pulsing star, visible in the night skies of most places in Cosmoria at its brightest. Most of the energy is lost.

Importance

Compared to those that live around stars, RNEs host a fairly small percentage of the population. These objects always represent the majority of a civilization's production capacity (if they choose to build these objects). Supermassive black holes make up the next largest block for production capabilities with regular stars making up the smallest average production capability cumulatively.