Switching off high currents with FET or IGBT

Do You mean like load switch? In that case i'm also interested of all the experience from others and all possible information so i can decide the most efficient practices.. I need to design a load switch for one solar powered project.. I have 30A dc relays in stock, but they are bit too close spec vise since they may need to drop the load off in some cases from full current (eg. in fault situation) and load is typically in the range of 26-27A..(voltage will be highest at 80V) so in my playbook that's a bit too much asked from a relay.. also their coil alone consumes 1W and i've measured about 5W loss from contacts at around 22A.. Now..i see that if i'd put 4 of IRFP4310's parallel as a low side switch i'd be losing only <2W total..And since it's solar, when there is very little sun, the relay coil will consume it's power all the time as per here, the switch conduction loss would be non existent.. I have a circuit in my head already, but at this point i'm usually very interested comparing stuff and parameters and component selection up until the point i'm making a proto..