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Comment by pjc50 | Hacker News Reader

> Economically infeasible I assume, but is that because of increased hardware costs

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.

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So if you want to generate more energy, "buy more land" is cheaper than "add tracking"? Seems like a solid answer, thanks.

Tracking does not significantly increase the amount of available energy out of a plot of land. It just reduces the amount of PV panels you need to efficiently utilize it. If you tile land with horizontal PV, all photons that hit that land hit them.

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.

https://www.canarymedia.com/articles/solar/a-100mw-solar-far...

I think a while back solar panels got cheaper than the curved mirrors used in molten solar based solar thermal plants.

'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.

More (cheap desert) land, more roofspace, more air above parking lots. It's also a matter of reliability, cheap moving parts = downtime.

Your calculation is way off. Getting 8kWh a day from a single 400Wp panel would already require 20 hours of operation at theoretical peak power, so under real-life conditions you can only expect a fraction of that per day.

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.

Ugh, I did 1kWh = 1000 watt-seconds, which should be 3600 watt-seconds, so the calculations are off by a factor of four.

£0.30 per kWh is also optimistic over the lifetime of the panel.

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 :)

I have 22 solar panels rated at 370w, I live in Phoenix Arizona where it’s normally cloud free and sunny. I have them facing southeast and southwest. My most productive panel produces about 2.5 KWh a day.

Not that I disagree with the conclusion, but you’d get no where near 8KWh a day from a 400W panel.

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