Why aren't sun-tracking solar panels in use at scale? Economically infeasible I assume, but is that because of increased hardware costs, increased maintentance costs, or just because they won't add much extra output?
Economically infeasible because of decreased hardware costs. Panels are so cheap compared to tracking systems.
(Quick envelope calculation: Amazon offered me a 400w panel for £200. Amortize that to about 6h of effective daytime use, that's 21600 seconds or 8kWh/day. 25 year warranty lifetime; derate that by, say, 20% to allow for degradation. 20 years is about 7300 days. That's about 58,400kWh. UK electric costs are all over the place at the moment, but at £0.30 that means .. you're buying £17,520 of electricity for £200.)
NOT INCLUDING BALANCE OF SYSTEM COSTS, solar panels are really cheap.
And once PV is cheap enough, the expense of tracking (and especially the maintenance expense of tracking!) to deploy a little less silicon does not make any sense.
'Cheap lower efficiency solar cells' became uneconomic when the non silicon cost of the panels became too high a proportion of the total cost. Because half the power per panel at 2/3rd the cost per panel doesn't pencil out.
This doesn't invalidate your point though - even if you're one order of magnitude off, your £200 solar panel will buy you about ten times its price worth of electricity.
Around these parts you get the spot price for any solar you generate. Prices can, and do, go negative.
In general prices tend to be low when the sun is shining and/or the wind is blowing.
So, you might even end up paying for the pleasure of providing solar power :)
Not that I disagree with the conclusion, but you’d get no where near 8KWh a day from a 400W panel.
The energy market systems are somewhat distorting perceptions of power in general and some reliability planners are worried that as older dispatchable generation goes offline for good, rotating blackouts may be in the future for many high demand areas.