LG300 vs SP327 Pricing Data

[ButchDeal]

Poway, what would you say is the added cost % for ground mount vs roof? Aside from the added variable cost of trenching and wire due to distance, is there really that much more cost in the supports for ground mounting? You would think some of that might be offset by lower labor cost due to easier and faster install on the ground vs roof. I am weighing both options right now like you probably did; roof mount SP vs ground mount LG.

Ground is not easier or faster. In many locations you need full footers etc. In some areas you can use earth screws or ballasted ground mount but that depends on the AHJ. You then have the added cost of the rack and assembling it, then attaching the rails and modules. Further in some areas you need some fencing around the ground mount system as well (either partial or full fencing).

[russ]

The house is your mount in a standard installation

With ground mount you start from zero and it generally requires a far more substantial foundation than you might expect. Fencing and protecting the equipment is not cheap either.

[J.P.M.]

Poway, what would you say is the added cost % for ground mount vs roof? Aside from the added variable cost of trenching and wire due to distance, is there really that much more cost in the supports for ground mounting? You would think some of that might be offset by lower labor cost due to easier and faster install on the ground vs roof. I am weighing both options right now like you probably did; roof mount SP vs ground mount LG. I have lots of ground space in Valley Center but don't want it right next to the house either. I think the trenching is whats going to kill me cost wise. Would you mind sending me your short list of the four installers? I am just getting started and it would save a lot of time narrowing the them down. How far out is your install?

Check with the county before any install, especially ground mounts.

[Poway]

Poway, what would you say is the added cost % for ground mount vs roof? Aside from the added variable cost of trenching and wire due to distance, is there really that much more cost in the supports for ground mounting? You would think some of that might be offset by lower labor cost due to easier and faster install on the ground vs roof. I am weighing both options right now like you probably did; roof mount SP vs ground mount LG. I have lots of ground space in Valley Center but don't want it right next to the house either. I think the trenching is whats going to kill me cost wise. Would you mind sending me your short list of the four installers? I am just getting started and it would save a lot of time narrowing the them down. How far out is your install?

COST>>>>>>>>>>>>>

My thoughts align with yours on the COST front.
+Trenching
+Support Structure
- Much easier to do things on the ground

But most installers do almost 100% roof mount. Their approach (My conjecture) to bidding ground is to just use their rule of thumb to cost the system and then add the cost of subcontracting out the support structure/trenching. In which case ground mount is >$0.50/W more. But installers who come from a ground mount background understand how much easier it is and the cost differential is reduced to basically the trenching cost.

FENCING>>>>>>>>>>>>>>

Others have responded with fencing costs etc. My guess is that this is not an issue for you (not a requirement for me either). If you drive around Valley Center you will see 10's of arrays and no fences. Benefit to having lots of space.

GROUND vs. ROOF>>>>>>>>>>>

My big reasons for going ground mount are

1) Don't have the risk of people messing up my roof (you can see pictures of horror stories on this site if you look... What do you do when you have a partially installed array and a roof that is destroyed.
2) Maintenance of roof with solar array is no fun.
3) With ground mount (and alot of land) can point array perfectly (perfect AZ and EL angles) for better production
4) Easier to fix. I don't think I would go with micro inverters (or optimizers which I went with) on roof as if one goes bad need to lift up.
5) Able to easily expand the system.
6) Able to use LG300 vs SP327 (don't need to pay large premium for space efficiency)

MY bottom line ... if you have the space Ground mount is CLEAR WINNER

References >>>>>>>>

I have outstanding reference(s) for ground mount in Valley Center. I'll PM you Saturday once I pull things together.

[Poway]

Poway, what would you say is the added cost % for ground mount vs roof? Aside from the added variable cost of trenching and wire due to distance, is there really that much more cost in the supports for ground mounting? You would think some of that might be offset by lower labor cost due to easier and faster install on the ground vs roof. I am weighing both options right now like you probably did; roof mount SP vs ground mount LG. I have lots of ground space in Valley Center but don't want it right next to the house either. I think the trenching is whats going to kill me cost wise. Would you mind sending me your short list of the four installers? I am just getting started and it would save a lot of time narrowing the them down. How far out is your install?

Haven't figured out how to reference another thread. But if you look at the pictures in this thread

"Solar install turning out really bad - looking for some help/advice please."

You will never want to be in his position.

[SoCalsolar]

Ground Mount is more expensive and

Ground mount solar is more expensive and takes more labor in the residential sector. It requires more labor and materials not less. Working on the ground is great if the work site is easily accessible by truck and crew, flat, and doesn't go over any leach, water, or gas lines. Very few ground mounts meet these criteria. Most often the solar is mounted far away from a suitable loading and unloading area on a dirt hill side. They require the same amount or more of racking and rails and also require 36"-48" deep concrete footings and an additional custom support structure depending on the terrain. Engineering and soil erosion certification is often required. Then you have to connect the system back to the main electric panel which usually requires trenching. Your overhead is no less expensive nor is your insurance as a business. I'm glad Poway got a great price on his installation. One really easy test is how many days this installation takes. The goal of every well run solar company is to complete the installation in one day. There is a tremendous financial benefit to do so supported by research done by Georgia Tech University. This means scaling your install teams to a size that can complete the project in one day. For example a 5kW roof mounted system should require a crew of 4-5 to complete in one day. A 9kW roof system is a 9 person job. My guess is Poway's job will be 3-4 days long and will put this notion of it's cheaper to work on the ground to rest. How can a well run company spend 2-3 times as long to install a ground mount unless it is more difficult. I'm guessing they will sub out the digging and structure work day one. Day 2 they will mount most of the panels, day three will be finishing the panels and the electrical. Day four if the install site is hard to access or they are not a well run company. I may be incorrect and I'm sure Poway will update us and let us know.