In far off-grid news, US space agency NASA is has announced a project aimed at eventually powering a human colony on Mars with a small modular nuclear reactor (SMR).

The Kilopower project aims to develop a SMR with a capacity of up to 10 kW that could run continuously for up to ten years.

Dubbed KRUSTY (Kilopower Reactor Using Stirling Technology), the device features a highly enriched uranium core with a central hole to accommodate a water-based heat pipe, which feeds into two Stirling converters.  According to NASA, it is the first-ever use of a heat pipe to extract thermal power from a fission reactor and the first use of a Stirling converter to produce electricity with a fission heat source.

Initial testing began in November and NASA is aiming for a full-power test in March.

To support a human colony on Mars and to produce enough fuel to allow the colonists to return to earth, NASA has estimated that around 40 kW of continuous power would be needed, meaning four or five reactors would be sent.

Off-grid energy sources such as solar PV with battery energy storage require heavy equipment that would make transporting them to Mars prohibitively expensive, NASA said, while the planet’s month-long dust storms would limit their effectiveness.

“A space nuclear reactor could provide a high energy density power source with the ability to operate independent of solar energy or orientation, and the ability to operate in extremely harsh environments, such as the Martian surface,” said Patrick McClure, Kilopower project lead at the Los Alamos National Laboratory.

David Poston, Los Alamos’ chief reactor designer, added that the technology “could be applicable to multiple NASA missions, and we ultimately hope that this is the first step for fission reactors to create a new paradigm of truly ambitious and inspiring space exploration.”