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The Universe Will Not Die a Heat Death
We assume that the universe is expanding according to the Lambda-CDM model with a fixed Lambda constant.
Imagine a central star, like our sun. Two artificial satellites are orbiting this sun in circular orbits in opposite directions. As the universe expands, the orbits of the satellites are elevated, and the satellites thus gain mechanical energy (the sum of potential and kinetic energy). This energy can be released by causing the satellites to collide or by simply having them graze each other. As a result, some of their kinetic energy is converted into heat, which can be radiated away as thermal radiation, and the satellites descend to lower, more inward orbits. The process can then begin anew.
It’s all about conservation of energy.
In your satellite scenario, the sum of kinetic and potential energy must remain fixed. This means higher orbits are slower orbits. In fact this is observable in man-made satellites that are moved to higher or lower orbits. There is no free ride.
In the “heat death” of the universe scenario, the total amount of energy in the universe is conserved (it is finite) but the volume of the universe keeps growing. On a long enough time scale the universe’s average energy per unit volume approaches zero.