Off Grid PV Install

[RumRunner]

I have an in-progress construction project in my house. My wife is a retired architect and she did all the plans, approved by Building & Safety with permits.

I am also a registered PE but inactive since I called it quits several years ago. So, we are (my wife and I) pulled the permit as owner contractor and I have friends (not on payroll) to carry out this project. This is not my first project, I've done three in the past.

My question is:

I intend to install an off grid solar array while we're constructing. I haven't brought this up with the city engineer (yet) because I'm not sure what he'll come up in terms of its impact to electrical appurtenances related to my existing electrical equipment, etc. I understand I'll need an isolation (transfer switch) but the power generated will not intrude my in-house electrical system.
I've seen solar panels installed in the neighbourhood, but they were installed when the houses were built.

The panels are not meant to provide power to the house either partially or otherwise. It would only be to provide power to my RV which is parked in the property ... to provide charging of batteries and perhaps some security and fire protection systems. Total planned solar output ~400 watts. Will this be considered portable even though panels will be permanently installed?
If any one has done this, I would appreciate any input.

Thanks

 

[ggunn]

I have an in-progress construction project in my house. My wife is a retired architect and she did all the plans, approved by Building & Safety with permits.

I am also a registered PE but inactive since I called it quits several years ago. So, we are (my wife and I) pulled the permit as owner contractor and I have friends (not on payroll) to carry out this project. This is not my first project, I've done three in the past.

My question is:

I intend to install an off grid solar array while we're constructing. I haven't brought this up with the city engineer (yet) because I'm not sure what he'll come up in terms of its impact to electrical appurtenances related to my existing electrical equipment, etc. I understand I'll need an isolation (transfer switch) but the power generated will not intrude my in-house electrical system.
I've seen solar panels installed in the neighbourhood, but they were installed when the houses were built.

The panels are not meant to provide power to the house either partially or otherwise. It would only be to provide power to my RV which is parked in the property ... to provide charging of batteries and perhaps some security and fire protection systems. Total planned solar output ~400 watts. Will this be considered portable even though panels will be permanently installed?
If any one has done this, I would appreciate any input.

Thanks

If your PV system connects with the utility through a transfer switch, then I think it will "intrude your in-house electrical system" and you'll be subject to whatever interconnection protocol that he POCO has in place. If it were totally standalone (not interconnected) you still might be subject to city codes but the POCO wouldn't be involved.

 

[petersonra]

690.1 Scope. The provisions of this article apply to solar
photovoltaic (PV) electrical energy systems, including the
array circuit(s), inverter(s), and controller(s) for such systems.
[See Figure 690.1(A) and Figure 690.1(B).] Solar
photovoltaic systems covered by this article may be interactive
with other electrical power production sources or standalone,
with or without electrical energy storage such as batteries.
These systems may have ac or dc output for utilization.

If it is only going to be used with the RV it might be simpler to get panels that mount on the RV so it is part of the RV and thus not subject to the NEC. These are readily available.

 

[ggunn]

If it is only going to be used with the RV it might be simpler to get panels that mount on the RV so it is part of the RV and thus not subject to the NEC. These are readily available.

OK, but there's not that much available real estate available up there.

 

[RumRunner]

If it is only going to be used with the RV it might be simpler to get panels that mount on the RV so it is part of the RV and thus not subject to the NEC. These are readily available.

Bingo!

I already have one up there which is a puny 165 watts. That's the reason I want a 400 watt array at least.. The other poster is right : there is not much real estate up there and this is the best physical size that I can squeeze between those vents, A/C ,antenna, Fridge and stove exhausts.

It's a small 28 footer Class A RV. The 165 Watt array is barely enough to top up 4 batteries.

 

[ramsy]

You could get high-watt panels that use concentrator cells, or add another 200 watt array to the side of the RV, parked facing the sun.

 

[GoldDigger]

You could get high-watt panels that use concentrator cells, or add another 200 watt array to the side of the RV, parked facing the sun.

Unfortunately AFAIK concentrator type panels will still take up as much roof space as flat panels for the same wattage. You save on silicon space but still have to intercept the same amount of sunlight.
Silicon that has a significantly higher conversion efficiency will cost a lot more.
This is the sort of area limited application where the premium price per watt if Sunpower panels might make sense. But possibly their panels will be too big to fit.

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[jaggedben]

How much space is available? For 500+ watts you need a space that's 7x5.5 ft. Or two spaces 3.5x5.5ft.

 

[RumRunner]

. . . Unfortunately AFAIK concentrator type panels will still take up as much roof space as flat panels for the same wattage.. . .
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Concentrator?

If this were the case, then what benefit does it offer? Sounds like euphemism by a top notch salesman who can sell a beach front property in Nebraska.

I've heard of Omaha Beach though.

 

[GoldDigger]

Concentrator?

If this were the case, then what benefit does it offer? Sounds like euphemism by a top notch salesman who can sell a beach front property in Nebraska.

I've heard of Omaha Beach though.

Solar PV in some commercial settings was designed to use lenses and/or parabolic reflectors in a tracking array to put light from a large area onto small chips of PV material. Liquid cooling was often required. It almost made sense when the active PV material was relatively expensive.
No known advantages with current technology.

Sent from my XT1585 using Tapatalk

 

[jaggedben]

Concentrator?

If this were the case, then what benefit does it offer? ...

The materials are substantially different, and thus the manufacturing cost structure is different. At one point a few years ago it looked like concentrated PV might be competitive, at least when one could use trackers and had a climate with reliable direct sunlight. Then conventional PV prices plunged further and CPV companies disappeared.

It was never viable for an RV application.

 

[ggunn]

The materials are substantially different, and thus the manufacturing cost structure is different. At one point a few years ago it looked like concentrated PV might be competitive, at least when one could use trackers and had a climate with reliable direct sunlight. Then conventional PV prices plunged further and CPV companies disappeared.

It was never viable for an RV application.

Economies of scale also come into play; it was never cost effective to build a tiny (like this one would be) CPV system.

 

[kwired]

How much is this going to cost and how long until it pays for itself compared to just using utility power?

I have some beach front property here in NE, you interested in buying it?








Ok, I have plenty of sand, but not an ocean. Can throw in a cheap plastic wading pool filled with water if that makes the offer more attractive though.

 

[RumRunner]

How much is this going to cost and how long until it pays for itself compared to just using utility power?
I have some beach front property here in NE, you interested in buying it?
Ok, I have plenty of sand, but not an ocean. Can throw in a cheap plastic wading pool filled with water if that makes the offer more attractive though.

It's not about economics. I'm more interested in safety. I don't want any hookups to the RV when I'm not around.


With shore power (power from house panel) I don't want any appliance and or any parasitic loads like sensors, voltage monitor, water level indicator to draw power from shore power. In other words, the RV would be totally “floating” on its own.


Ground fault is always a possibility especially in wet weather conditions.


I usually shut off (except essential loads like phone, thermostat etc) when I'm on extended vacation.
It's only my wife and I in the domicile but neighbors are a big help in notifying me or family members not living with us in case emergency arises.


Your offer for a beach front property in NE is interesting. I wonder if I could set in my lounge chair and watch the blue whales and dolphins go by for their summer breeding season down in Mexico.

 

[kwired]

It's not about economics. I'm more interested in safety. I don't want any hookups to the RV when I'm not around.


With shore power (power from house panel) I don't want any appliance and or any parasitic loads like sensors, voltage monitor, water level indicator to draw power from shore power. In other words, the RV would be totally “floating” on its own.


Ground fault is always a possibility especially in wet weather conditions.


I usually shut off (except essential loads like phone, thermostat etc) when I'm on extended vacation.
It's only my wife and I in the domicile but neighbors are a big help in notifying me or family members not living with us in case emergency arises.


Your offer for a beach front property in NE is interesting. I wonder if I could set in my lounge chair and watch the blue whales and dolphins go by for their summer breeding season down in Mexico.

Not wanting parasitic loads drawing from shore power isn't about economics? From millions of customers they do add up to the power supplier, for your one RV they are not really all that much compared to cost of alternative power sources.

Can't watch whales here, I can take you to beaches where you can watch migrating waterfowl every spring and fall though.