I drove 1800 miles in a Hydrogen Car

I am a car dork, and grew up in Utah in the high altitude. Before turbos and fuel injection was on everything altitude would change the tune on your carburetor, due to less atmosphere to use for combustion. My question is, what are the losses in the hydrogen fuel cell cars at higher altitudes, and have they found a way to gain that efficiency back? (Turbos for hydrogen cell cars?)