Draconic Power( Complete Arcane, p. 78)
You have greater power manipulating the energies of your heritage.
Draconic Heritage (CAr) ,
Your caster level increases by 1, and you add 1 to the save DC of all arcane spells with the energy descriptor of the same energy type as determined by your draconic heritage.
If the Energy Substitution feat is used to modify a spell, this feat will work if the new type of energy matches the energy type of your draconic heritage.