How much energy does annihilation take?

[Karimspencer]

Many people say that when mixing matter with anti-matter , energy is released according to e=mc2 however how much energy does it take to mix matter with antimatter which leads to annihilation .

 

[mfb]

It does not require energy. In the case of charged particles, they even attract each other as they have opposite charge.

 

[DaveC426913]

The problem with matter and antimatter is not the amount of energy you need to expend to get them to come together - the problem is the amount of energy you need to expend to get them to keep them apart.

Both matter and antimatter will happily float around and come into physical contact with each other (including the walls of the container or any air in it), whereupon annihilation will occur spontaneously. To stop this from happening the moment you create any amount of anti-matter, you must devise a way of keeping it away from matter. This is usually done with magnetic bottles. Which require energy.