ATF.  Rosatom has developed the technology and manufactured experimental uranium disilicide fuel pellets for light water reactors as part of a comprehensive program to develop tolerant fuel (ATF). The advantages of such fuel composition are its high density and uranium content, which will make it possible to switch to longer fuel cycles), high thermal conductivity combined with low heat capacity, and also a lower operating temperature of the fuel pellet compared to uranium dioxide composition. Rosatom has been conducting reactor tests using ATF since early 2019.