[usrusr]

Heliostat installations used to be common when panels were so expensive that spacing them out wide enough to keep them from shadowing each other when angled for dusk/dawn made sense. Now heliostats are only done in exceptional situations, for example I've seen some that didn't seem to be particularly old on rugged terrain were the quantity approach would be costly as well and easy foundation opportunities are sufficiently far from each other to prevent peer shadowing anyways.

But I do wonder if heliostats might see quite a revival in agrovoltaics: there, you want a certain distance between panels anyways, and perhaps the plants won't mind if you steal a little more light off-noon in exchange for less shadowing at noon. Electricity supply/demand would certainly applaud this bias, in a market with lots of photovoltaics a Wh at noon is certainly worth less than those closer the the periphery of the daily sun cycle.

And if you do agrovoltaics right, the structure will be expensive anyways (making the markup for heliostat insignificant) because imho it's still just an unfinished prototype if the structures for holding the panels aren't designed to double as an overhead rail system for farming powertools that could become a considerable efficiency gain over the century-old game of tractor vs mud.