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tgsovlerkhgselyesterday at 11:25 AM5 repliesview on HN

Looking at the graphs, the tracking arrays may have the added benefit of generating power in the mornings and evenings. If everyone builds non-tracking arrays, power during peak will become almost worthless if solar is a big part of overall generation capacity, so the economics might change even with panels being cheap.

Of course, just building 2x as many permanently tilted panels might also work.

Edit: the article actually addresses this: "[fixed setups] can pack 250% more installed power into the same space when compared to a single-axis array" - so even if only the power in the morning/evening has value, there is little reason to install tracking ones.


Replies

hinkleyyesterday at 6:39 PM

This is one of the areas where double sided panels reportedly win out. You can orient them to morning/evening light and they shed heat by convection better. Hot cells produce less electricity, which is why it’s difficult to construct Maxwell’s Demon from eg infrared-sensitized photovoltaics and band gapped radiators.

leoedinyesterday at 1:42 PM

Yeah - you can’t talk about renewable energy generation without also considering when it is generated.

Then future price of energy will be incredibly time dependent. Finding a way to generate at a different time than everyone else - whether by east/west panels or time shifting with batteries or building a different kind of renewable generation is where all the big profits will be.

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ceejayozyesterday at 2:09 PM

Power during those lull periods will get expensive, and that’s likely to result in some farms with permanently tilted panels that prioritize those periods over peak overall production.

Space is cheaper than maintenance and breakdowns in many cases.

ac29yesterday at 3:10 PM

> If everyone builds non-tracking arrays, power during peak will become almost worthless if solar is a big part of overall generation capacity

During peak solar yesterday in California wholesale power was $5-6/MWh (<1c/kWh).

The CA grid is routinely over 100% renewables during springtime. The excess is handled by having a lot of batteries, exporting energy, and curtailments.

Calwestjobsyesterday at 2:39 PM

but, 70% of MY! yearly households electricity consumption is literally into [PV!] hot water. Hot water tank is cheapest energy storage device on planet. and i do not have to worry to shower in noon, i can just charge my water tank during day, even when im not home. and use hot water in evening. for very little price - no need to use heat pump, resistive heater is super cheap. hot water tank can be made even DIY to lower price even more.

utility charges me so much for electricity that even tho i payed for 15 kWp roof mounted east west system literally literally ORDER OF MAGNITUDE more than prices showed in that article, AND i still save money by not buying electricity from grid !

that how much utilities are charging us, yes they need to manage all those wires, manage power plants, etc. i do understand where that cost comes from, but still, solar in residential is so cheap that installing PV on roof and directly consuming it will save you money.

So for industry/ manufacturing there will be extremely high incentive to add PV + battery even when it wont cover 100% of their loads. utility+ onsite PV+battery.

Again, back to my hot water system, 80% of year i am 100% "off-grid" for hot water [PV!]. even on days it is cloudy ! And 99%-0% of PV rest of year... And from april to October my electricity draw from grid is almost zero.

so whole residential USA can be essentially "off-grid" huge part of year with just small battery, your tv, notebooks draw almost nothing over the course of the day compared to your energy need for hot water. and less residential is on grid, easier it is to manage electricity for other sectors of economy.

this contraption from ETH Zurich can store iron/iron oxide to generate hydrogen, without storage loss! for years, without compressing hydrogen and without other cons of "standard hydrogen storage. essentially it can be thought about as hydrogen storage - it can "store" 10s of megawatts inside of a standard basement. - [https://ethz.ch/en/news-and-events/eth-news/news/2024/08/iro...]

and you do not need to make electricity from that hydrogen, you can heat your house directly with hydrogen, just by replacing 30$ burner in your existing furnace!

so you complain about "peak" power excess, and i say and i show it to you that this "peak" solar power can be used to charge that extremely cheap storage device in summer and expend that storage over winter for heating house and making hot water. when sun is not shining.

and again, calculate how much kWh is your need for heating and how much is for hot water and you can clearly see that extremely huge part of current residential energy need can be either "onsite off-grid" with this contraption + small LiFePO battery or to be on-grid and take only small loads like tv, notebooks from grid and having heating + hot water "onsite off-grid". and most importantly cheap.

ratio of kWh for your heat and for your other appliances ! ! ! !

So essentially we can charge our heating system in summer, store energy WITHOUT LOSS until winter and heat with that energy in winter. right now!

just sketch/draw for yourself timeline containing - PV + storage contraption in that link + small LiFePO battery. and you can see how huge part of energy we do not really need to draw from "grid".

small towns can even make their own shared storage, prices for SEASONAL energy storage are even lower then current prices for electricity drawn from grid....

So this physical, economical actual contemporary possibility makes me mad every time i see just another youtuber or other kind of influencer, post about just another battery technology promising who knows what, in who knows what timeframe.

we do have energy storage technologies capable of providing citizens of USA with clean energy RIGHT now, RIGHT here. for whole year, day and night. without buying one drop of oil from tyrants, dictators who literally literally kill people right at this moment.

[https://apnews.com/article/russia-ukraine-war-drones-kharkiv...]

this world is so frustrating ! XD

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