How to convert electrical voltage in volts (V) to energy in joules (J).
You can calculate joules from volts and coulombs, but you can't convert volts to joules since volt and joule units represent different quantities.
Volts to joules calculation formula
The energy E in joules (J) is equal to the voltage V in volts (V), times the electrical charge Q in coulombs (C):
E(J) = V(V) × Q(C)
So
joule = volt × coulomb
or
J = V × C
Example
What is the energy in joules that is consumed in an electrical circuit with voltage supply of 15V and charge flow of 4 coulombs?
E = 15V × 4C = 60J