william mook wrote:
The ultimate in solar collectors must be the deposition of solar
collectors onto the solar surface. The sun puts out 3.86x10^26 watts
of power. Distributed over a sphere whose radius is equal to the
radius of Earth's orbit this falls to a little less than 1,400 watts
per square meter. But on the solar surface this energy density
exceeds 60 megawatts per square meter! Clearly, if we could figure
snip
But of course, we need to figure out how to make something work
reliably on the solar surface. Which I haven't done.

Trivial matter of engineering...
60Mw/m^2 is not a big problem.
A millimeter of copper will only have about 140C across it at 60Mw/m^2.

The problem is the cooling.
You can only radiate to the sky, no convection is possible.
It may be possible to get a hair under solar temperatures by using
coatings that are more efficiant radiators than the solar atmosphere
(no absorbtion bands) but you'r still looking at well over 5000K.

This is a problem, as everything melts at this temperature.

It's probably easier to move out a bit, as you'r not charged by
the square meter for solar surface.