The Sun is not a limited resource, not until we're a K2 civilization anyway -- and we're no where close to K2. The other materials in solar panels are abundant and reusable. There is plenty of unoccupied desert to build on.

In what way are resources limited?

> The Sun is not a limited resource,

Photovoltaic cells and the materials to use them _are_ limited and the amount of power produced by solar today is _very_ limited.

> not until we're a K2 civilization anyway

People should read less science-fiction and look at the actual world as it exists today.

Yes, let's look at the actual world as it exists today: the land area required to power the annual global energy consumption (110 TWh) with the inefficient solar panels that we have today is smaller than the US state of New Mexico.

How's that for pragmatics?

Hyper pure quartz for photovoltaic solar is limited.

Are you thinking of purified silicon? Silicon is made starting with quartz, quartzite, or similar minerals rich in silicon dioxide. Crude silicon always requires additional purification for solar uses after it's initially created, so the purity of quartz going into the electric furnace isn't critical.

You can see the process flow from raw materials to completed PV modules here:

http://oasis.mechse.illinois.edu/me432/ME432_L31_Nov4.pdf

No, I'm talking of high purity silicon necessary for the crucibles used to manufacture polysilicon wafers suitable for PV solar panels.