How many joules are there in a led bulb?

1) The power use of bulbs is specified in units of power, not energy. In other words, watts - which means joules per second.

2) Light-bulbs come in different capacities.

3) It is incorrect to say that the energy (or power) "is in" the light-bulb. The light-bulb simply transforms one type of energy to another, using electrical energy which is NOT stored in the light-bulb.