The 1 MW units he is selling won’t even produce electricity. They produce heat (assuming they work as advertised) but not enough temperature to create steam.
Let's for a second, assume it works, I don't think it does but go with it. NYC practically runs on as much steam as electricity. Having this thing supply the steam needs for NYC would free up a large amount of electrical energy, (actually, they'd just open the flood gates and bypass the turbines) but there are a lot of uses for steam in a stationary environment besides electricity.