Let's determine the various forms of energy used by an old-fashioned alarm clock with springs.
The type of energy the spring has after it is wound can be called the elastic potential energy.
The potential energy can be defined as the energy possessed by an object due to its position due to some zero position.
Therefore, after the spring is wound, it will have the potential energy due to the arrangement/position of the spring.
As the alarm clock runs and performs its various functions, the spring loses energy.
Since the spring is in motion, it loses energy and the potential energy lost becomes kinetic energy.
Kinetic energy can be said to be the energy of an object due to its motion.
Also, due to friction, the some of its potential energy is converted to heat energy.
Therefore, in other words, the energy initially in the spring which is the potential energy, is changed into the kinetic energy and the heat energy.
ANSWER:
The initial energy which is the potential energy is converted into the kinetic energy and heat energy.