The fuel needed, with reflector in nuclear power plant, in order to generate sufficient neutrons to sustain a chain reaction, would be
Nuclear Reflector:- A layer of material immediately surrounding a reactor core that scatters back (or reflects) into the core many neutrons that would otherwise escape. The returned neutrons can then cause more fissions and improve the neutron economy of the reactor.
The presence of reflectors in nuclear power plants decreased the leakage of neutrons. In nuclear power plants, due to reflectors, less fuel is needed to generate sufficient neutrons to sustain a chain reaction.