Cheap DIY solar fence design

Watched Fisherman's Life on YT (in California) recently build out some panels had to pay for inspection granted different design than a fence

Some very rough numbers from memory:

- 20 panel + 10 microinverter bundle: $5600

- cost to ship the bundle: $700

- conductor: $450

- steel/pvc conduit for conductor sheath: $350

- strut for racking: $500

- 3” steel conduit for ground mount: $5000

- concrete and tube forms for vertical post footers: $400

- augur/trencher rental: $500

- brackets/fasteners: $600

- tools: $500

- electrician work to upgrade service panel: $2500

- electrician work for hookup and disconnect install: still TBD but I’m guessing more thousands

- time spent x my current hourly salary as a programmer: I don’t want to think about it haha

Probably a bunch of stupid little stuff I’m forgetting. Just gas to go on supply runs is probably over $100, although I always tried to batch runs with other normal errands.

The most expensive parts of projects can be surprising, at least to me. I also recently invested in my own fuel transfer pump to transport home heating fuel instead of paying for delivery. 55 gallon drums: $20 each. Pump: $200. But the most expensive part was actually the 15 meters of arctic grade fuel hose at over $400.

A lot of construction work in general is priced around labor being atleast 50% of the total cost.

Ground mounts are far more expensive, not only because of how strong they need to be to support the panels under strong winds and snow without deflection, but the anchoring can be complicated depending on the site.

Some people can just hammer spikes into the ground, fill with epoxy, and their array is anchored. For my yard, I have to dig 4-feet down below frost line, through incredibly rocky clay soil, and bury (and concrete) 4x4 posts. On top of those posts goes the (expensive) metal rails to mount the panels. For just 10 solar panels it's gonna cost me ~$1000 in materials and many hours of digging.

The metal U-channel rails I'm looking at using will cost around $40/pp (10-ft), and I need at least 10 of them. In theory a cheaper option could be wooden boards like 2x8/2x10, but they're significantly heavier, bulkier, and would still be difficult to mount to.

This construction lets me build the array however I want, including adjusting angle (I'll have 4 pre-set angles for each season). This design is still cheaper than the cheapest pre-fab ground mounts, which are metal legs which go for ~$110/pp. You need ~2 legs per panel, though in some cases you can share one leg for two panels. For 10 panels you still need at least 11 legs, so at least $1100, before cost to anchor them. And that's a fixed angle. The adjustable angle ones are more like $185/pp.

It is the cost of scaffolding to get up to the roof, labour to install the panels, electrical certification, etc.

And so on :)

I think this graph sheds some light on your question:

https://www.nrel.gov/solar/market-research-analysis/solar-in...

What happened in the last decade was that solar panels ("Module" in this graph) got very very cheap. They used to cost $3 per watt in 2010, but now only cost $0.3 per watt.

This extreme price drop happened thanks to technical innovations (such as commoditization of PERC cells), and the large-scale production in PRC.

Metal components ("Hardware - BOS" in this graph) did get cheaper in the same time frame ($0.6 per watt to $0.5 per watt), but their cost cannot be reduced as much exactly because they are just a piece of metal i.e. there is no low-hanging fruit in Metallurgy.

The labor alone to mount the PV panel costs more than the PV panel. A union electrician costs a contractor $100/hr in a medium sized metro area with fringes and wages.

The mount and installing the mount cost more than the PV panel as well.

I’m unsure why everyone is posting about rooftop solar and rooftop mounts, the vast majority of PV panels are installed in solar fields, not on roofs.

I actually run and sell commercial electrical work, for what it’s worth.

What is it about solar panels that makes everyone want to use these really expensive mounting solutions? Is it just because they're trying to engineer a full 30 year lifespan right from the start?

You will still need the conduit for the wire of course, at least up to the inverter. That will add up pretty quickly if your mounts are spread out.

Human Labor, the most neglected factor when discussing rising infrastructure costs.

For ground mounting, site preparation is required. Probably one wouldn't want to see their panel system get some slope year after year.

I’m in a very windy location but they are heavy enough to not budge.

Similarly, if you want to do a permitted installation, you generally need to use UL-certified inverters and batteries -- fewer shocks and fires. That's a different pricing tier from the "trust me bro" equipment you can find online.

Meanwhile, a panel's main failure mode is not producing enough power. They're relatively easy to replace when they fail to do that. Price incentives are better aligned for that system component.

Talk to your AHJ before spending any money.

Also expect a dove colony to enjoy the new comfort. All your neighbors will thank you for their homes turning into guano rocks, a sight once reserved to adventurous travelers.

Their nests, which will quickly accumulate under your roof's panels, offer not one but two existential threats for your home: They can catch fire when too dry, but also act as a water barrier, pushing the water into your roof.

Takes up a smaller footprint of land, and PV panels themselves are now so cheap and last so long that it borderline makes sense as a fencing material even if you don't connect them to an inverter and power and anything with them.

https://www.infolink-group.com/energy-article/solar-topic-it...

But even putting aside the tariffs, I'm in the same boat as you - residential/consumer solar in the US is a disaster - everything goes through shady installation companies, the labor and permitting costs are enormous, it's nearly impossible to buy panels yourself at the market rate.

Panels and enphase on Craigslist are so cheap you don’t have to worry about it. Max out what you’re allowed with your main electrical panel size and you’ll never regret it. Don’t even consider doing less than the maximum. You will never meet anybody who believes they added enough solar after a year of ownership

Now, you would have built not a cutting-edge system, but a relatively inexpensive one, with a minimum of red tape and financing shenanigans.

(Edited: typos.)

If you're paying someone else to do it, the panels will likely be <10% of the cost.

Part of the issue is what you're optimizing for. If you have yearly net-metering, and you just want to max out the number of kWh you generate over the year, vertical probably isn't that great. If you are off-grid or are paid hourly based on power prices or some other scheme, you generally want to maximize your worst-case power production rather than maximize yearly production. Generally batteries are only sized for a few days worth of storage or so. You can't store power from the summer and use it in the winter. Vertical panels at high latitudes also produce more power earlier and later in the day when the sun is really low. Bifacial vertical panels also generally get more bifacial gain, especially on cloudy days.

It's really a question of maximizing worst-case performance vs. average-case performance.

And usually you have enough power during midday but not in the mornings and evenings, where these would produce the most power, sort of flattening the power curve.

Also panels are really cheap, like 70€ per piece

This is still conventional wisdom, yes. It assumes that you need to maximise utilisation of solar panels, and act as if they are rare and expensive. But they are now neither rare nor expensive any more.

Also, as the other comment pointed out, if you "maximize area that is facing the sun", you get most generation at mid-day. Adding in some generation that is most active in early and late day balances that out, as most power is used then.

And you can just throw more panels at the problem. It's not a constraint any more.

OP has 370W bi-facial panels that cost $100, I recently had solar installed the in UK with 465W single-face panels which would have cost ~£100 each to buy in small quantities, my installer clearly paid less (and charged 3x).

It has also been my experience that a few degrees off with decent enough sun (and we don't get amazing sun here in the UK) makes practically no difference to the generation; my arrays are facing E-SE and S-SW and I can slightly exceed the rated specs in the peak of summer when the sun is mid-way between both arrays and not pointing "directly" at either.

There are a lot more considerations to get into e.g. in areas with lots of snow verticals are significantly less affected and benefit more from reflection, in summer vertical E/W bifacials have a “double hump” which provides more generation in the morning and evening, verticals take less floor space so you might be able to get extra panels or get panels at all, N/S bifacials have better winter production unless your slanted panels are “detuned” from perfect summer angle (or even better have a tilt mount you can update every few months, but that is not cheap).

Because why not have a fence that at least generates some power instead of a fence that does nothing! Costs are not that much more, 2k is easily spent on a bigger fence and this way, you don't have to get up and hustle, our fence does it for you!

When vertical not much of an issue and the reflection from the snow appears to work well with bifacial.