Ok, according to my in depth research, wiki, the filament of standard incandescent light bulb will reach a temperature of roughly 2500 K. According to Stefan-Boltzmann, the power radiated from an object at temperature T (K) is given by P= A ε σ T^4 . Suppose the filament has a radius of 1mm and is 25.4mm long. The filament has a surface area, A, of 1.6E-4 m^2. Further assume emissivity, e, is 1.0. The radiant power is then calculated is then 367 watts. According to wiki, a 100 W bulb has a resistance of 144 ohms when it is lit. If the bulb is plugged into a standard 120V outlet, the electrical power delivered to the bulb is P = V^2/R = 100 W. For a 1 second time period 100 J of electrical energy power the bulb, but somehow 367 J comes out. Where does the extra 267 J come from? Is the 267 J stored in the filament material and then released from the filament as it burns?