It's cool, your comment suggested you understood that typical G-radiation releases more energy than the sun in 10 Gyears.
This was for the Gamma-ray burst, but you can calculate the energy of the gamma radiaiton by using the equation
E=hf
h is planks constant and f is the freq of the gamma EM wave. Try it and see what energy you get :)
Thanks for the clarification @physics.benjamin. I will employ the formula.
It's funny how rusty one can get when you stop using something. I could remember I learnt this equation in my first year in school. Thanks for jogging my memory.