(The energy is released when it's needed simply by letting the water run back down the mountain through turbines that convert the energy into electricity.)
(The energy; is released; T:when it's needed simply by letting the water run back down the mountain through turbines) (it; 's needed simply; ) (turbines; convert; the energy; into electricity)
The energy it turbines
is released 's needed simply convert
T:when it's needed simply by letting the water run back down the mountain through turbines
the energy into electricity