Would it not be better to use ### instead of Nuclear fission to generate Power?

When you talk about generating "power" you are really talking about generating electricity. Electricity is generated by turning the crank on an electrical generator. Whether it is hydropower, natural gas, coal or nuclear fission, the end result is that the mechanical energy from those sources is used to turn the crank on a generator to make electricity. Anti-matter would not make a good energy source for that application because most of the energy created from a matter/anti-matter reaction is in the form of gamma radiation. Gamma radiation is a higher energy form of x-rays and is lousy at heating up water to make steam to turn a turbine to turn the crank on a generator. So, while you are correct that anti matter would make a great energy source, the energy created from those kinds of reactions is almost useless for generating electricity. Sorry, physics is an unforgiving *****.