Vertical Solar Panels Are Out Standing
68 points
by lxm
6 hours ago
| 16 comments
| hackaday.com
| HN
floatrock
5 hours ago
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Article doesn't give a whole lot of context, but there's two key innovations here:

1. Bi-facial solar panels: can take in sunlight from either end

2. Mounting bi-facials vertically so they can take in sunlight from both directions.

I've been hearing experiments about these for a few years now. There's three main benefits to the vertical arrangement that could, given certain situations, make it more economically valuable:

1. In places with high-albedo snowy winters, this arrangement can boost winter production, which if you have snow, tends to be the energy-heavy time of year.

2. Keeps panels cooler. Panels lose efficiency when they get hot, and by having them vertical, they can run cooler. Losses in less direct sunlight are somewhat offset by efficiency gains from cooler operations.

3. More power during shoulder periods (anti-duck-curve). Especially in places like California that have high solar penetration, prices for excess energy are minimal during peak solar activity. Vertical arrangements give more power in the morning and evening, which is when traditional fields are just ramping up or ramping down. Thus, even if you're making less power overall, you can be making more valuable power by having more production during these ramp-up/ramp-down periods.

Unclear how much of an effect these counter-acting forces actually add, but I understand solar developers are looking into these arrangements.

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dinfinity
1 hour ago
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The anti-duck-curve is actually really, really pronounced for east-west mounted bifacial panels.

The panels still don't generate any electricity at night of course, but other than that the output is an almost perfect inverse of the conventional equator-facing angled mounted panel output.

Just search for "bifacial solar panels graph".

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Havoc
5 hours ago
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The one gotcha is that roof mounting for vertical is a bit of a headache & the structural support is often precisely the wrong way round.
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bryanlarsen
4 hours ago
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This is an interesting application; it sounds like they've worked through a bunch of those issues: https://cleantechnica.com/2025/09/27/bifacial-rooftop-vertic...
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Havoc
1 hour ago
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I meant more on a classic home with an A-frame like roof.

Don't think it's a coincidence that the demo vid they're showing off is a flat factory roof

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estimator7292
16 minutes ago
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Yeah, I mean the peak of such a roof is the only practical place for it. I'd say this style of mounting is simply not appropriate for all types of roofs, and that's not exactly a bad thing, just geometry
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water-data-dude
4 hours ago
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Interesting that they list wind as one of the places where vertical panels have the advantage - my intuition would have been the other way around, with angled panels doing better in windy conditions. Wind uplift isn't something I'd have even thought about.
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blackoil
3 hours ago
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Can they be used in apartment. We don't have roof space but can hang them vertically from balcony. Bi-facial won't work but what about mono-facial?
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aitchnyu
2 hours ago
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Germany allows apartment tenants to hang panels on their balcony and feed 800W for their needs.

https://www.canarymedia.com/articles/solar/how-germany-outfi...

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thijson
4 hours ago
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Vertical also doesn't take up very much real estate.
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scotty79
4 hours ago
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if you put up just one row and don't mind the shadow
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jillesvangurp
4 hours ago
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A comment that I heard recently is that in some places using solar panels is literally cheaper than using wood panels for fences.

I'm not sure how true that is of course but it does make you think a bit. The optimal place where to put solar panels increasingly is becoming "wherever you can afford to". If vertical space is what you have, why not use it?

People in apartments don't have access to roofs. But they might have balconies. Balcony railings can fit a few solar panels usually.

You can buy solar panels for use on balconies in the supermarket in Germany. They only generate a few hundred watt. But that can add up to close to something like a kwh per day if you get a lot of sun on your balcony. At 40 cents per kwh. That's 12 or so euros per month. I pay about 70 per month currently. And I can get a couple of balcony panels for something like 200-300 euros. And I might get some money back on those even. The idea with balcony solar is that it might offset part of what your fridge uses. You simply plug it into a wall socket and your fridge takes that power instead of from the grid. All safe and approved equipment, the inverter cuts the power if there is no grid power.

I haven't done this (my balcony faces east and only gets a few hours of sun in the early morning). But it's easy to see how this could work.

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wiredfool
4 hours ago
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Quick look near here -- wood panels are ~50-99eur for .9->1.8m x 1.8m fence panels. I've priced out 550W solar panels (which should be about 1x2M) for about 100£. (Both retail, but different countries (ire/uk))

So, not price parity but also only about a factor of 2 or so. On the other hand, Ali Express panels are about half that UK price at a 10 panel quantity, with unknown shipping.

I'm kind of eyeing the concrete block wall in the back garden currently covered by a hedge.

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childintime
2 hours ago
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Sadly in Germany you mostly miss out on one big advantage one often gets in sunny countries: power during outages.

That said, WW3 terrorism acts may change that. It could be wise to have at least some backup.

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somat
12 minutes ago
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Almost no private solar installations give power during outage, for the most part they use something called a grid tied inverter. This uses the power grid to shape the waveform and costs about a tenth of what a self shaping inverter costs. the unexpected downside, no grid, no power.

I have yet to find conclusive evidence if it is possible to use a small full inverter to drive grid tied inverters, that is, have the grid off capability of a full inverter with the cheap cost of a grid tied inverter. It sounds reasonable, but I don't see anyone doing it.

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jws
5 hours ago
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At 45°N latitude, I keep mine nearly vertical year round. I used to adjust them 4 times a year for more optimal production. There are issues beyond angle of incidence. Being nearly vertical keeps the snow off in the winter. In the summer it reduces the cleaning required (it's a sea bird rookery, so that's kind of a lot). Beyond that, the telemetry needs are constant year round so if the panels can cover the needs in the winter, then summer is no problem.

My current strategy for small installations when you have an equator facing wall or fence is slap the panels on it and be done with it.

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malchow
5 hours ago
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In addition to bi-facials starting to work quite well, HNers may be interested in a rising class of ultra-low-mass material that has come out of work at Stanford and Intel in transition-metal dichalcogenides (TMDs) (e.g. for MoS₂, WS₂, WSe₂, etc.).

It turns out these enable a very high specific-power PV cell that adds another even more attractive production curve behind what is happening in vertical bi-facials. See e.g.:

https://ee.stanford.edu/frederick-nitta-koosha-nassiri-nazif...

https://www.arinna.xyz/

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xnx
6 hours ago
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It's such an interesting optimization problem. Maximizing annual production isn't the only goal. It's also about: never running out of power, having surplus power when useful, minimizing installation cost, minimizing maintenance cost, guarding against dust and hail, minimizing use of land, etc.

Approaches range from straight vertical to flat on the ground: https://erthos.com/earth-mount-solar/

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goda90
5 hours ago
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Earth mounting reminds me of when I used to daydream about autonomous, mobile, solar panel factories to cover huge swathes of sandy desert with solar panels. I doubt the mobile factory thing would ever make sense, but autonomous installation would be really cool.
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colechristensen
3 hours ago
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The cost is now at the point where we don't care so much about actually using every watt and when we do need more watts at a particular time we add more in "inefficient" configurations to supply it.

Whole industries are going to pop up to take advantage of the intermittent very cheap electricity. Also there will be a competitive balance between the cost of storage and the "cost" of non-optimally aligned solar panels.

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dylan604
6 hours ago
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Am I reading this correctly? Vertically they produce 77% compared to 90% of the tilted panels? In what graph is the lower number better?

Also: "Specifically, [Dave] is using bifacial solar panels– panels that have cells on both sides. In his preferred orientation, one side faces South, while the other faces North. [Dave] is in the Northern Hemisphere, so those of you Down Under would have to do the opposite, pointing one face North and the other South."

Isn't that the same thing? Is one of the sides specifically meant to face the sun? Maybe I'm just not as knowledgeable about solar panels, but what sunlight is being harnessed by the backside of the sun facing panel? Are they catching reflected light, otherwise, they are directly in shadow.

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detaro
6 hours ago
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Bifacial panels usually have one side that's a bit more more efficient than the other. The backside can catch reflections, sky light on overcast days, ...

But it's usually more common to orient them east-west, so they have peaks in the mornings and in the afternoon/evening, which combines well with other solar panels that are mounted south-facing, or might even just match your electricity consumption pattern better.

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Linosaurus
5 hours ago
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> Vertically they produce 77% compared to 90% of the tilted panels? In what graph is the lower number better?

77% of the ’normal orientation’ per year, but the graph and 131% value is for a day in winter (January 15 this year). At least that’s my read.

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JumpCrisscross
5 hours ago
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I also believe vertical panels produce more than flat panels in the mornings and evenings, thereby giving them anti-duck curve properties.
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dylan604
5 hours ago
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So one day of the year is producing 131% yet still only averages 77% for the year? Yeah, that sounds like a good trade off. /s

I'm still trying to decide if the entire post is trolling or not. Nothing about it sounds sane to me.

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Xylakant
5 hours ago
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So your problem is that during summer, average solar production is much higher than in winter in the first place. So to ensure that you have sufficient energy in winter, you can either overprovision heavily for summer use (lots of flat panels facing south) or you can sacrifice summer efficiency to gain winter efficiency - vertical panels do that.
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fckgw
5 hours ago
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It's not just about production, it's also about reducing maintenance costs (don't collect snow, less dust build up on panels) and land usage. If you can take that 77% average, but maybe stick a couple more panels on land to reach your energy goals in an overall smaller footprint with less maintenance work, then maybe it's a good solution to specific problems.
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adgjlsfhk1
5 hours ago
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If you had a solar panel that produced half as much power as regular, but produced power at night that would be a massive win. This is a less extreme equivalent. It produces less power than a normal solar pannel, but it produces power at an important time (when regular solar panels don't produce much power).
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petters
6 hours ago
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> Isn't that the same thing?

Yes, it’s a joke.

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dylan604
6 hours ago
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If bifacial panels are made so each side is the same making orientation not an issue, then sure, hahahaha (not really. it's a lame joke). If there is a back side, then you absolutely need to reverse the orientation depending on hemisphere. It would be better stated that they need to be pointed towards the equator. If these are literally reversible, it seems like wasted money to me as one side will never produce as much as the reverse does.
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dessimus
4 hours ago
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The graph confused me for a moment, but then realized the graph is showing the winter with SNOW on the ground, not the general case. So in the winter the vertical panels produce more power than tilted panels in very specific conditions and depending on how often that occurs, it may make up for the loss in efficiency during other times of the year. I'm guessing the vertical panels gain some advantage of the sun reflecting off the snow and into the vertical panel that the tilted panels do not, especially when the sun is at low angles to the horizon.
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Workaccount2
5 hours ago
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The hemisphere talk is a joke, the situation being shown off here is one where there is snow in the ground, which greatly increases the amount of sunlight hitting the backside panel.

This is also in January, when the sun in Ohio is very low in the southern sky. So north/south oriented panels are much more ideal.

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jszymborski
6 hours ago
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> Isn't that the same thing?

I had the same reaction. I noticed the top comment reading "some of us live in the southern hemisphere" so maybe this was a quick edit and not thought through?

Unless one of the sides of the panel is meant to face north, but that doesn't sound likely

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msandford
6 hours ago
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If you look at the far right hand bar the B-N/S says 131% which is the highest bar on the chart. So it's producing more than the standard tilted slightly south orientation from what I gather. The legend is a bit hard to read for sure.
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simpsond
5 hours ago
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Utility scale fields tend to have single axis trackers which can optimize output. They are expensive though. I wonder if a manual rack that could lock at 30 or 90 could work and be cost effective.
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gorfian_robot
5 hours ago
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I read somewhere (maybe in Dave's youtube comments) that the price of fencing is high enough that some folks have used bifacial vertical solar panels as a fence.
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balderdash
4 hours ago
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How do vertical panels handle wind loads?
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otherme123
3 hours ago
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Two axis panels put themselves vertical on high winds, but facing perpendicular to the wind direction. So it depends on the wind direction.
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vzaliva
3 hours ago
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bifacial panels indeed produce more electricity. but does it justify the cost increase? simply speaking if bifacial panels cost 2x, do they produce anything close to 2x electricity?
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mixmastamyk
3 hours ago
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Looked like a lowest 6% boost in the winter, but more in the summer. Likely makes sense as panel prices decrease.
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bryanlarsen
3 hours ago
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The rule of thumb is that bifacial increases production by 35% for a 10% cost increase. YMMV.
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lacoolj
4 hours ago
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Is the title (here and on the article) supposed to say "outstanding" as in "amazing! wonderful!" or is it deliberately "out standing" as in ... standing...out...actually, I don't even know if this is a valid phrase.
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NortySpock
3 hours ago
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That's the joke, both are valid uses of the phrase and sound alike.

"My scarecrow is the best in the business! He's out standing (outstanding) in his field!" (i.e. a field in a farm, or in his area of expertise)

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k2enemy
3 hours ago
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I am excited to be here while you experience your first pun!
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lacoolj
3 hours ago
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Still need the explanation of what pun I'm missing, but looking forward to seeing what you come up with :)
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fortranfiend
3 hours ago
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They're out standing in the field. ...I'll let myself out.
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scotty79
4 hours ago
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I wonder why 30 deg was chosen. If you want to maximize energy production in the winter they should be installed more vertically so that for most of the winter the angle between the sun rays and the panel is around 90 deg.
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wzdd
5 hours ago
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In their field?
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marcodiego
5 hours ago
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Come on: "Specifically, [Dave] is using bifacial solar panels– panels that have cells on both sides. In his preferred orientation, one side faces South, while the other faces North. [Dave] is in the Northern Hemisphere, so those of you Down Under would have to do the opposite, pointing one face North and the other South."

That is not the kind of thing I come here for.

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YcYc10
5 hours ago
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I'm assuming that's a joke, but who knows.
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magicalhippo
4 hours ago
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As Dave has shown in previous videos, bifacials are not symmetrical, and the backside produces less power under same conditions. So N-S would be different from S-N orientation.
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hunterpayne
5 hours ago
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This setup almost certainly took more carbon to make than it will ever replace. This is usually true anywhere it snows regularly. There are a couple of exceptions, but unless you are above 7000ft of elevation you are just making the problem worse. This guy should donate this setup to someone in Mexico where it would make sense.
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wolfram74
4 hours ago
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I'm juggling a baby approaching lunch time at the moment, so I can't go into too much depth on this paper[0] I found 40 seconds ago, but the conclusion seems to think that solar panel EROIE in siwtzerland is somewhere between 7 and 10, which as a proxy for carbon intensity, /probably/ means it will actually result in net carbon reduction.

[0]https://www.sciencedirect.com/science/article/pii/S030142151...

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Implicated
4 hours ago
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Congrats!
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mixmastamyk
3 hours ago
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Very short term thinking. How will it improve if no one tries?

Reminds me of the critics of digital photography circa the year 2000.

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AnotherGoodName
4 hours ago
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You need to back that up with genuine analysis and proven studies.

The reason i say this is that in some parts of the world capitalist things like building renewables to make or save money is politicised as a left or right wing issue with people arbitrarily for or against purely on that bucketing.

The politicisation is stupid and doesn’t even align well to any traditional left/right political divide other than ‘at one point in history they fell on one side or the other of the issue’ so now they are stuck there. It’s interesting with the perspective of someone who’s experienced a different countries right/left wing politics which have completely different views on various issues. As in there’s often no reason for such things to be in either side honestly. In fact for certain things that never got politicised in the USA such as battery storage the red states are leading the world in grid connected battery installation rates since it’s so profitable and the topic has avoided being bucketed into a left/right category all the while blocking offshore wind farm installation which has been bucketed as such.

Anyway due to this politicisation you cannot just post ‘this renewable initiative doesn’t work’ without honest analysis to back it up. This would need to include the massive drop in solar power and battery prices that have occurred recently.

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