Most likely, your belt broke. If that's all that happened, then it shouldn't be too expensive. If something driven by the belt seized, and CAUSED the belt to fail, then it could get more expensive. Belt failure would cause all of the symptoms you described, as the belt runs the alternator (hence the power system message) and the power steering pump (no power steering.) I'm not sure if the V8 engines have water pumps that are run by the drive belt or the timing belt, but if it's the drive belt, that would also explain the fans running longer... hopefully, you didn't overheat the engine!
'98 Volvo S70 GLT-170k miles- my everyday driver. Mods: 16T turbo, injectors, ECU, TCU, wheels, and interior trim from a T5.
'02 Volvo XC70-130k miles- Wife's car
'95 Volvo 850 T-5R
Black. Rescued from oblivion, needs help, am now providing said help.
'93 Volvo 940 Turbo wagon, 141k miles- Workhorse/ toolbox.
'88 Mercedes 190E 2.3- bought to fix up and sell, but I kinda like the little old beast, so I'm holding on to it for a little while.