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Comment by masklinn | Hacker News Reader

I strongly recommend watching Dave’s entire video, it’s really extensive and interesting.

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.

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What if we do vertical bi-facial panels, mounted on a rotating circle that rotates to align the panels with the sun (north-south or east-east or in between) depending on the time of the year. Wouldn't that be the best of all worlds right now?

On a theoretical basis yes but a tracking array gets a lot more expensive, and a lot less reliable. The rotating circle also takes a huge amount of ground space.

If you put the panels in a diagonal (NW - SE), and you rotate each panel on its vertical axis, the need for space would be limited to a series of circles the diameter of the panel width.

No expert on the topic but surely a manually rotated system achieves the benefits of tracking without the overhead of installation and maintenance for an automatic system. As long as the panels are easily reverted to default position when no one can go and rotate them through the day (thinking domestic setup in the garden).

Plenty of people have gardens and land that is tended to multiple times through the day anyway (for gardening, animals, workshop activity etc).

> the need for space would be limited to a series of circles the diameter of the panel width.

Now your panels start shading one another.

Maybe I wasn't clear, but in the precise NS and WE configurations, there should be no shading.

As soon as you add moving parts to your setup costs and maintenance explode. It's usually better to just buy more panels instead.

Depending on where you live a system that allows to manually change the tilt of your pannels once per month could be nice. You get a free 5-15% boost, where I am in Europe the optimal yearly tilt is ~40 degrees, in peak winter the optimal tilt of ~70 degrees would shed snow much more easily.

You're right on motorized trackers though, way too complex and expensive to make sense for most people

> Depending on where you live a system that allows to manually change the tilt of your pannels once per month could be nice. You get a free 5-15% boost, where I am in Europe the optimal yearly tilt is ~40 degrees, in peak winter the optimal tilt of ~70 degrees would shed snow much more easily.

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.

Moving parts? We're talking about something like a pipe that's a hotdog down hallway slip fit onto another pipe here. With zero maintenance that will still have a service life that exceeds several generations of panel.

Plus at least one motor plus sun tracking controller. All of that has to operate 24/7, all year.

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.

You don't need a motor. You need a recurring calendar reminder to send someone out there to spin them all 2x per year at whatever day you determine to be the ideal crossover point where you want to switch between NS and EW.

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.

Panels have warranties of 25 years.

A pipe on a pipe will last close to 100 if you don't screw up the details...

vertical panels also kinda work as fences and aren't that much more expensive (actually might be cheaper...)

This. I am seeing this more in Austria and makes sense since a solar panel is really one of the most mass produced fence panel size things in the world. By choosing them you are also guaranteed replacement panels in the same dimensions compared to buying some random fence panel

Over the long term, there might be less wear and maintenance on either configuration. I'm guessing the vertical panels wins there.

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