Multi-modular power plant with off-grid power source

A multi-modular power plant may include a plurality of on-site nuclear power modules configured to generate a power plant output, wherein one or more of the nuclear power modules may be designated as service module units which are configured to generate a first portion of the power plant output. A remainder of the nuclear power modules may be configured to generate a second portion of the power plant output. A number of power plant systems may be configured to operate using electricity associated with a house load of the power plant, wherein the first portion of the power plant output is equal to or greater than the house load. Additionally, a switchyard may be configured to electrically connect the power plant to a distributed electrical grid. The distributed electrical grid may be configured to service a plurality of geographically distributed consumers, and the switchyard may be configured to apply the second portion of the power plant output to the distributed electrical grid. The switchyard may further be configured to apply at least part of the first portion of the power plant output to the power plant systems during a loss of power from the distributed electrical grid.