Can I just set the panels on the ground?

[Kevin322]

I have a certain amount of space to put panels in my yard. Panels are so cheap and mounting is so expensive, that I'm thinking about just putting the panels flat on the ground. It will be less efficient, but I can just buy more panels to cover essentially the entire available area, so all of the sunlight I could get access to is hitting a panel.

My question is how/whether I need to secure the panels in such a scenario? My understanding is that you generally need to be concerned about the panel at an angle acting as a sail, but that wouldn't be an issue here. Can I just set them on the ground, and leave it at that?

 

[jimf909]

Yes, you can.

Apparently, Will does it all the time and rolls a generator over them. It'd be nice to secure them in some way. Also, does Indianapolis get snow anymore? That'll cut down on production on snow days. What's the lifespan of this installation: 20 yrs or six months? It seems you'd eventually want to mount them properly unless this is a project property with a lot of "that's just a temporary solution" solutions.

 

[scrubjaysnest]

Just because it lays on the ground doesn't mean it won't become a Frisbee. Had that happen once. Panel survived.

 

[LakeHouse]

Panel survived.

Just making a note on your silence about the fate of any bystanders...

 

[scrubjaysnest]

Just making a note on your silence about the fate of any bystanders...

There were no bystanders. I was in the process of setting up the panels

 

[Lt.Dan]

Yes, notice that where Will has placed all his panels, there is very high walls/buildings preventing wind from picking any of these panels up.

 

[Kevin322]

Yes, you can.

Apparently, Will does it all the time and rolls a generator over them. It'd be nice to secure them in some way. Also, does Indianapolis get snow anymore? That'll cut down on production on snow days. What's the lifespan of this installation: 20 yrs or six months? It seems you'd eventually want to mount them properly unless this is a project property with a lot of "that's just a temporary solution" solutions.

This is a serious question: why mount them properly? That's expensive with little benefit. The only real benefit I can think of is preventing them from flying around during high winds. Which I certainly want to do--if it's a potential problem. Is it? How would something like that be calculated?

One thought I had for securing them is to pass a steel cable through each housing, and tie down the steel cable to a rod in the ground. That wouldn't keep them from jostling around, but it should prevent them from becoming frisbees.

And yes, snow will cut down on production. I can brush them off as needed, or just leave them covered if I'm feeling lazy. I'd probably lose ~30 days a year from that--not too worried about it. The lifespan of the installation is 20 years (although I do have plenty of "that's just a temporary solution" solutions around ).

 

[highwaypirate]

One of my coworkers didn't want to pay extra for mounting brakcets for his panels. He ended up just grabbing pallets from the free bin and bolted his panels to those. It still allows airflow and pallets are fairly heavy, I'd think it would prevent it from becoming airbourne?

 

[Lt.Dan]

One of my coworkers didn't want to pay extra for mounting brakcets for his panels. He ended up just grabbing pallets from the free bin and bolted his panels to those. It still allows airflow and pallets are fairly heavy, I'd think it would prevent it from becoming airbourne?

Definitely not. I've tried just holding onto panels in 15-20mph winds and it's downright scary. Pallets are not heavy enough

 

[Bop]

I wouldn't leave them just lying on the ground- it is amazing what gets blown around when the wind picks up- I had some sheets of plywood lying on the trailer that I left unsecured after unloading some of them, it was getting too dark, and I had a dinner to go to, so just left them lying flat on the trailer...
There was the typical Aussie 'summer afternoon thunderstorm' rolled through, and when I got home- all of the sheets were lying all over the place- even though they were lying flat on the car trailer, the wind still picked them up... the furthest was over 30m away from the trailer...

And that wasn't super strong winds, hadn't even knocked any branches down from the gumtrees- had much stronger wind in other storms - those sheets would have been in the neighbours place if they were stronger (and he's over half a kilometre away lol)
Done quite a bit of roofwork with panels over the years, and even a gentle breeze catching one is a struggle (especially when you are on a steeper roof- not fun...)

My temporary arrays are angled, but I ended up filling the IBCs to stop them moving in the wind- there's three IBCs in total, with 3000L of water in them- now THAT'S not moving... (they have survived 90kmh with gusts of up to 120km during a storm that took the roof of two nearby houses...)

 

[LakeHouse]

The only real benefit I can think of is preventing them from flying around during high winds. Which I certainly want to do--if it's a potential problem. Is it? How would something like that be calculated?

Yes, it is a potential problem. Wind flowing over and around things does counterintuitive stuff sometimes, and in certain circumstances, 'picking up a flat thing off the ground' could absolutely be one of them. And it turns out calculating something like that is:

• Very, very difficult in complicated cases where wind patterns are affected by nearby structures. Think: build a wind tunnel and a scale model of the space if you want an actual good answer.
• Much less difficult in the 'open-field' case. But then the answer is: yeah, if it gets windy enough it'll pick them up and toss them around.

Probably best to at least secure them to the ground.

 

[chrisski]

I’ve had panels secured with a cable to prevent theft. Came out the next day with the panels blown to the end if the cables.

I’ve also had panels flat on the ground get blown, again secured by a cable.

My 25 LBS 100 watt panels blow lying flat on the ground taking off at 15 -35 knot winds.

 

[jimf909]

This is a serious question: why mount them properly?

I wasn't intending to be facetious (although I may have hoped for some humor to seep in).

Why mount them properly?

1. Safety
2. Panel life: it seems that if they're just lying on the ground for 20 years that there's an increased risk for damage to the panels from twisting, things falling on them, etc. I suggest checking with the panel mfr. to see if the warranty is at risk if they're not installed on a mount.
3. Space efficiency: it seems that real estate might eventually be useful for something else. How much space would be saved mounting them on a mount and using fewer panels due to increased productivity? 33% 50% Eventually that may come in handy.
4. Panel productivity: angling the panels will improve productivity. Having more is nearly always better even if we don't use it now.
5. Code compliance: this is between you and your county. You may be fine or your county may have something to say eventually.

Not every project has to be implemented perfectly from day one but risks to safety should be a primary factor in deciding what not to do.

 

[Will Prowse]

I never made a video about it but my panels that are lifted in the back have a cable running through them and I anchored them to the slab below. We get some crazy winds out here, but as lt. Dan mentioned, there are buildings all around to prevent high wind. Especially that low to the ground. I have had two panels on the corner move quite a bit and one time a panel flipped over. Hasn't happened since using the concrete anchors.

My recent array is not lifted up on one side so I'm just leaving them there. They won't go anywhere unless you tilt them on one side.

The solution to mounting panels on the ground is to use a ballast mount. I went to the solar conference this year in San Diego and they had a few options.

Here is what we need for the future:

 

[Will Prowse]

Wind is extremely dangerous though and panels need to be secure if they are on the ground. It's easy to do, but if a big storm comes it's very important.

I used to kiteboard back in the day and the force generated by wind is absolutely insane.

 

[JRH]

Yes, notice that where Will has placed all his panels, there is very high walls/buildings preventing wind from picking any of these panels up.

This is a serious question: why mount them properly? That's expensive with little benefit. The only real benefit I can think of is preventing them from flying around during high winds. Which I certainly want to do--if it's a potential problem. Is it? How would something like that be calculated?

One thought I had for securing them is to pass a steel cable through each housing, and tie down the steel cable to a rod in the ground. That wouldn't keep them from jostling around, but it should prevent them from becoming frisbees.

And yes, snow will cut down on production. I can brush them off as needed, or just leave them covered if I'm feeling lazy. I'd probably lose ~30 days a year from that--not too worried about it. The lifespan of the installation is 20 years (although I do have plenty of "that's just a temporary solution" solutions around ).

Expensive .?….Expensive will be the lawsuit if they lift up just a bit and get caught by the wind and decapitate the neighbors dog.… google some charts on the Ft Lbs per sq ft of the pressure generated on a flat surface by wind at different MPH….it’s scary…
Easy way out is mount the frames on 2x 4s or 4x 4s ( cheap) and run some rebar( cheap) on the four corners into the ground at the very least.
seriously , wind isn’t your friend..

I’m buildin a few ground mounts now like you want to do for some large panels …
mine will be removable , moveable , slightly tilted ,but anchored securely …no way would I just lay em on the ground..
J.

 

[doksinc]

I priced ground mounts exclusively before permitting, found the ballasted mounts very favorable in price vs the price of galvanized metal these days. Not to mention the difference in labor is a huge difference.
My recent install:

 

[Will Prowse]

I priced ground mounts exclusively before permitting, found the ballasted mounts very favorable in price vs the price of galvanized metal these days. Not to mention the difference in labor is a huge difference.
My recent install:
View attachment 195131View attachment 195132

And so easy to clean. Or swap panels.

 

[Kevin322]

My recent array is not lifted up on one side so I'm just leaving them there. They won't go anywhere unless you tilt them on one side.

Wind is extremely dangerous though and panels need to be secure if they are on the ground. It's easy to do, but if a big storm comes it's very important.

I'm confused. Is your recent array that is not lifted up on one side secured to anything? It sounds like the aren't, but you also said panels need to be secured.