An example will help clarify.

The earth-moon system, like the universe, is expanding. Both are expanding at about the same rate: the universe at about 72 parts-per-trillion-per-year (ppt/yr) and the moon's orbit at about 100 ppt/yr. (1 km/sec/mpc = 1 ppt/yr) Both are "almost perfectly" balanced (not "perfectly"!), but not quite. The expansion rate of the cosmos and the earth-moon system are both "almost zero." Neither is in "perfect" balance, but both are very close.

Is "dark energy" causing the moon's orbit to expand? No, it is rotational energy of the earth. The earth's rotational energy is being transformed into gravitational energy of an expanding earth-moon system. Is dark energy causing the universe to expand? No, it is "light energy." More specifically, radiation eneregy in all forms (radio waves to gamma rays; neutrinos; gravitational waves; & cosmic rays). Visible matter radiates energy, which is why it is visible, and this energy drives the expansion, according to the principle of Conservation of Energy.

In other words, Dark Energy is light energy!