A plant for production of liquid hydrogen, comprising a liquefier, a source of gaseous hydrogen connected to the liquefier, a first source of electricity connected to the liquefier in order to supply the liquefier with electricity, at least one additional source of electricity which provides an amount of electricity which is intermittent or variable over time and which is connected to the liquefier in order to supply the liquefier with electricity, and an electronic controller, wherein:
- the liquefier is of the electric type and has a variable cooling power which depends on the electrical power consumed;
- the electronic controller is adapted and configured to manage a refrigerating power of the liquefier in order to produce liquid hydrogen at first thermodynamic conditions when the latter is supplied with electricity at a predetermined nominal electrical energy level, and produce liquid hydrogen which is subcooled with respect to the first thermodynamic conditions when the liquefier is supplied with electricity at an energy level exceeding the said nominal level.