utility ores is the metllury package that includes magnesium, phosphorus, saltpeter, potash, sulphur and bitumen.
also, even if the quantum tank can hold the steam, the main problem is getting the steam enough turbines to be a viable alternative to non steam. each turbine only gives 50 eu/t and needs 2 pipes of steam to it (assuming you use the industrial pipes), which means you need a vey large number of steam turbines for a large power plant, and is not feasible to manage the steam piping for the 20 turbines need for 1000 eu/t ( not to mention all the steel spent running that)
it would be much cheaper and easier to run 20 mark-1 reactors and 1 breeder, than to do the steam system.