But you cannot make energy from their motion, E=MC2 still applies.
They possess "motion without energy"[20]—their apparent motion does not represent conventional kinetic energy.[2
Did you read about the ones they created? they required massive amounts of energy and only exist briefly.
https://en.wikipedia.org/wiki/Time_crystal#Thermodynamics
There is no model of these things where they can be used for a perpetual motion machine. They explicitly say that energy is conserved, as it always it. If you want free energy buy some solar panels or a micro hydro unit, build or buy a biomass gasifier, time crystals and geet engines are not ways to generate energy.
RE: Is The Oil Industry Suppressing Alternative Fuels? We can run an engine on tap water!