The quoted "1 TW of photovoltaic cells per year, globally" is the peak output, not the average output. They're only about 20% higher peak output in space… well, if you can keep them cool at least.

It is more than 5x less expensive to get surface area on earth’s surface.

Fortunately there are no downsides to launching solar cells into space that would offset those gains.

Does that include all the required radiators to vent heat?

Now do waste heat.

Solar cells have exactly the same power rating on earth as in space surely? What would change is their capacity factor and so energy generation.

And how much of that power would be spent on high speed communications with Earth that aren't, you know, a megabit or two per second