most solar panels do not currently use indium, gallium, selenium, cadmium, or tellurium, none of which are rare earth elements (though indium is pretty rare)
the solar panels that used those cannot economically compete with silicon pv for utility-scale solar any more (perhaps that will change)
silicon is also not a rare earth element (and is not at all rare)
evs and wind turbines can use rare earth elements, it's true, but it's just a relatively minor engineering tradeoff not to use them
"According to Philip Pesavento, Cove then managed to refine the composition of the alloy close to Zn4Sb3 – a zinc-antimony alloy with proportions of 4 parts zinc to 6 parts antimony. That, we now know, is also a semiconductor. However, it has a bandgap of 1.2 eV – very close to the bandgap of silicon (1.1 eV). Consequently, it turned his thermophotovoltaic generator into a photovoltaic generator:
“In his enthusiasm, Cove probably made up a larger number of plugs and somehow got the proportions “wrong” on one batch. He then measured an even larger voltage. Finally, he made a careful study of zinc-antimony alloys and found that the 40-42% range zinc alloy gave the highest voltage (compared to 35% zinc in ZnSb). Having – accidentally – discovered Zn4Sb3, the higher bandgap of this semiconductor meant that it no longer worked when it was exposed to the heat from a wood stove. However, it worked even better when it was exposed to solar energy – because it was now converting far more of the visible spectrum of sunlight efficiently into electricity.”
Using colored glass filters, George Cove determined that most of the response was from the violet end of the spectrum and only a little from the so-called heat rays. His earlier PV plugs had responded equally well to heat rays and violet rays, while the older thermoelectric generators (German silver at both sides) did not respond to the violet rays at all.
Bring back the Schottky solar cell?
Schottky junction solar cells have commanded only a small amount of attention from researchers and corporations – few solar cell designs use metals in the active region, other than for contacts. [22] Nevertheless, Philip Pesavento believes that it would be worthwhile to attempt to fabricate some Schottky solar cells according to Cove’s design:
“If it could be demonstrated that Zn4Sb3 (bandgap 1.2 eV) can be used in a photovoltaic cell, there is a good chance that such a solar cell design will be sustainable. It would be a good candidate for a quick EROI and have an acceptably long operational life with a surplus energy output over several decades. It’s astounding that everyone seems to have missed this material and its application to photovoltaic cells and that no development has been done – even after researchers briefly recognized it as being a possible option in the early to mid-1980s. It fits in the category of a premature discovery which should mean it could be developed very quickly in this day and age.”
antimony is toxic, rare, and expensive, and silicon is none of these, so antimony-based solar cells are unlikely ever to be an economically superior alternative to silicon-based solar cells
the solar panels that used those cannot economically compete with silicon pv for utility-scale solar any more (perhaps that will change)
silicon is also not a rare earth element (and is not at all rare)
evs and wind turbines can use rare earth elements, it's true, but it's just a relatively minor engineering tradeoff not to use them