Vertical Solar Panels Are Out Standing
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The article discusses the use of vertical bifacial solar panels, which produce 77% of the energy compared to tilted panels, and the discussion revolves around their efficiency, cost-effectiveness, and potential applications.
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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.
Yes, it’s a joke.
(Also: if the panels do have a "preferred" orientation, you can offset that by installing them in an alternating pattern, or at random.)
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.
I'm still trying to decide if the entire post is trolling or not. Nothing about it sounds sane to me.
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.
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.
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
Approaches range from straight vertical to flat on the ground: https://erthos.com/earth-mount-solar/
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.
The other discouraging part is that as I understand it it's tricky to build the systems out a little at a time, e.g. start with five panels and no battery, add another five panels and batteries to the mix a few months later, add another ten panels another year later, stuff like that, without ending up with a lot of duplicated equipment and kind of a mess of an installation.
Especially if you're not trying to achieve an off-grid/backup solution, microinverters keep your install and additions simple.
https://enphase.com/store/microinverters
Also, when you start small you don't need or have any use for a battery. Produce less than you consume or be happy with a little bit of waste and you don't need the complexity of a battery.
There are plenty of well planned paths towards a slow accumulation of pieces and features.
That is not the kind of thing I come here for.
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.
Don't think it's a coincidence that the demo vid they're showing off is a flat factory roof
I think it'd be interesting to look at how these might be colocated with crops.
1. https://www.ted.com/talks/jenny_chase_solar_energy_is_even_c...
I'm not sure what a quarter-mile of solar panels four feet high would cost, or whether they'd survive the occasional cow rubbing on them. Neat idea, though.
Partial-shading-tolerance designed modern panels will quite happily tank partial shading, and as long as you keep the shading aligned in the design direction of the panel you will have within ~30% of the usual efficiency (i.e., still like 14% instead of the usual 20%) relative to the remaining irradiation that your panel is still receiving after the shading took it's chunk.
Just take care to ensure the shading conditions for all panels that are passively combined into an array are sufficiently same, or at least behave in a way that the modules can bypass effectively to not loose an unshaded panel's yield due to one panel in the group having some shade on it.
https://www.canarymedia.com/articles/solar/how-germany-outfi...
https://diysolarforum.com/threads/plug-in-balcony-solar-beco...
Edit: For larger installs (many vertical panels, >1kw), agree that balancing and a dedicated circuit is likely more optimal.
800w sounds low to me, especially on 120v in the US, but the rules may have been in place for older less efficient / bulkier panels in mind.
Bypassing the grid and using your own storage infrastructure is AFAIK not allowed in Germany (there are heavy taxes on electricity, that you would be omitting - similar as to how you technically are not allowed to make your own Schnaps at home due to taxing).
If people started plugging a 2kW grid tied inverter in a normal power socket - as is the case for balkonkraftwerk - houses would start catching on fire.
Nobody wants that. Yes, regulations are necessary for a safe and civil life.
Due to recent issues out there: calculate worst winter peak voltage and make sure there's a healthy margin to the peak allowed safe/no-damage input voltage to the MPPT/charge-controller/inverter.
Panels eat less of their own current at any given operating voltage, the colder they are. And winter mornings after soaking in night cold are worst case conditions for that as they had no time to heat up yet for the first minutes past sunrise.
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".
But shading is also a factor. If you want to get unobstructed sun across the whole day, you need to be built on a nice curve of a hill? Or build just a straight line of panels?
We currently have:
- summer optimised array: almost flat, 15 degree, optimised for maximum power on sunny summer days, mostly runs our cooling
- winter/morning array. Points SSE, 65 degree incline. Gets great energy in the mornings, and on winter mornings. Performs surprisingly well in overcast conditions. Generates about the same power in midwinter and midsummer.
- winter/afternoon array. Same as the above, but SSW.
18kW total faceplate capacity, in reality we peak at around 5kW, but have that for about six hours of the day for 9 months of the year. Also means I can run three arrays on two MPPTs as the two tilted arrays are basically mutually exclusive as to when they make power.
The other reason for leaning towards vertical panels is cleaning. The flat panels accumulate a crust of crap (pollen, soot, dust) that cements on there fast, and requires vigorous scrubbing to remove. Kills 20% of the capacity unless I get up there with a broom every six weeks. The 65 degree ones I have not had to clean once, as stuff just slides off them.
That, and a pallet of bifacials is now cheaper than a pallet of monofacials.
This opens the interesting prospect of hinged vertical pannels that could be adjusted for the season, opening up the V in winter and closing it in summer
A vertical panel has infinite higher efficiency that a flat-mounted one, if a flat-mounted one couldn't be constructed due to floor requirements.
yes, and sometimes it's a positive effect.
source is e.g. https://theconversation.com/how-shading-crops-with-solar-pan...
Notably though grazing pasture mostly doesn't complain and if mounted suitably (IIUC low enough density and high enough start above the ground), it can co-exist with effective nature preserves.
Notably while the N/S bifacial have an amazing showing in sunny winter day with ground snow (as well a significantly higher resilience against snowfalls), the year round testing he did shows that the performance crater in spring, with half the performance of standard inclined panels, and none of the morning / evening advantages of E/W bifacials.
In the end, the N/S verticals have a worse year round production than every other setup, and significantly worse than standard, but if you live in a location with a fair amount of winter snow and can swing (heh) it a tilting mount could be an interesting configuration for winter.
Now your panels start shading one another.
Plenty of people have gardens and land that is tended to multiple times through the day anyway (for gardening, animals, workshop activity etc).
You're right on motorized trackers though, way too complex and expensive to make sense for most people
Yup, that's what I was referring to as a tilting mount in the original comment, a pivot and tracks to tilt the panels up/down to set them at whatever's optimal for your latitude and time period, or completely vertical if you're in a snow-heavy region.
The necessary engineering might not be worth it anyway, given current panel prices, unless space is a bit of a premium.
Depending on your local climate, that has to be sun and rain proof. (Most Nema 7 "3D printer" motors are not waterproof... Ask me now I know )
Nothing a quick hack job can't solve for you, but if you want to sell it (and make sure your customers will be satisfied for decades) it quickly adds up in price.
The panels can be stayed in their correct positions by a trash tire or whatever buried in the ground with two chains poking out to clip to the panel corner.
None of this is rocket science. This is all stuff that has been proven out over the past 200yr of fence and gate construction.
Similar could be used for changing between tilted and vertical though you'd need more material.
This might work a lot better.
One big trade off/risk is a large vertical panel essentially becomes a sail in high winds.
I guess you also don't need to remove the snow from the panels?
[0]https://www.sciencedirect.com/science/article/pii/S030142151...
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.
Reminds me of the critics of digital photography circa the year 2000.
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.
That said, WW3 terrorism acts may change that. It could be wise to have at least some backup.
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.
In the US they cost a lot more, but they still exist; there's a 750-watt unit at Horror Fright for US$70: https://archive.fo/1pzdK
The most common solution to that is a switch that goes through fully disconnected in the middle, and I've even seen a sliding metal plate used that interferes with at least one or both circuit breakers.
I'm using a Fronius GEN24 Plus (10 kW) which can be used off-line/off-grid (called 'Full Backup', to use it you need some extra switching gear between the inverter and the utility hookup, which gear that is differs from country to country) and provides single-phase power in its default configuration (they call it 'PV power', basically a 3 kW single-phase connection which comes alive when the utility hookup goes down). While this inverter was slightly more expensive than the Chinese alternatives the difference was more in the range of 30%, not '10 times'.
Or is that what you’re suggesting with the Chinese inverters?
There are Chinese inverters which support island mode as well, my reason for choosing a European manufacturer is not related to this type of functionality. He who controls a large fleet of inverters can control the grid - and bring it down. I prefer to keep sole control over what my inverter does and do not allow it access to the internet, keeping it on a separate wired network (wireless access to the inverter is disabled) which is only accessible by a dual-hosted container on the server-under-the-stairs. It is through this container that I control the inverter and extract data for power management purposes - turn on heavy loads when the sun is doing its thing and/or imported electricity prices are at the lowest rates for the day. While I could (and would) do the same with a Chinese inverter I'm not convinced that would be enough to keep third parties from accessing the device though either some embedded 2/3/4G, LoRa or similar device.
I installed the panels on a barn I built in 2019 and installed the inverter in 2022 - long before my suspicions about the potential for such covert control channels were 'proven' [1] so my initial caution turned out to be justified.
[1] https://www.reuters.com/sustainability/climate-energy/ghost-...
I can't speak to the accuracy of that, as I was speaking to a salesperson and I didn't go forward with the project so don't have any personal experience to add.
Outages are rare enough here in Germany that few people go the extra effort and cost to install the necessary equipment. But with the right equipment (which is available if you go look for it), you can definitely get this installed. In places like Australia, outages are more common and it's generally not that costly to upgrade your setup to support proper islanding and it's more common for people to design their systems for this.
Of course people if feel compelled to prepare for WW III that might be a good motivation. On the other hand, we'll have bigger issues if it comes to that.
It is not a solution for everyone, but redoing all my electricity hook-up, getting a whole-house battery and a three phase backup option would easily cost 20k. And it would cost a tonne of space, cause all this battery and inverter stuff needs to be close to the main connection (where I don't have space). The solution I chose was only 1200 for a 2kWh battery with built in inverter for 4 panels. And the battery is actually portable, I could technically use it for camping. Output is limited to 1200W AC from battery, or 2000W AC when there is enough solar input. To me spending 1200 Euro to have some electricity in case of WW III (or some significant sabotage) felt worthwhile
...that might have been my comment. Or someone else repeating it. I was wrong, I misremembered "in X years solar is projected to be cheaper than wood panels for fences". X being, IIRC, maybe 3 years?
The point still stands, but the fact doesn't. Not til ~2028.
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.
"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)
The next question is what is the cost and difficulty of creating the foundations necessary to handle the worst wind you can expect?
Nice example of hacker humor.
Also, couldn’t the tilted bi-sided panels also have some reflector send light to the rear side?
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/
I run a solar company, and for ground mount systems the cost of the frames and foundations is more than the panels. With vertical PV it doesn't matter if power production is maximized, what matters is return on investment.
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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