Advice for an incremental build with micro grid-tie inverters

[getut]

Yes I'm a newbie here... this is my first set of questions on my quest to going solar.
I feel this question needs its own thread even though some of the questions I ask have answers in other threads, I have never seen anyone try to tie them all together the way I want to.

I have wanted to start a solar project for years but never have becaue of the initial cost. I have recently discovered the micro-inverters which I think will allow me to grow a system incrementally. I want to run my plan by you guys and get specific advice for how to pull together these many tasks that get asked here into a single project.

Goal 1: When it is all said and done, I want a grid-tie solar electric system that generates a net positive over a 24 hour period (generate more than I use) but I don't really care about batteries, so I don't mind going on grid at night time. I just want my day-time solar generation to offset that cost of being on grid at night.

Goal 2: I want the system to be able to work off grid when needed. I already have a 6500 watt diesel generator that won't run the entire house so I'll be using the generator to provide voltage to "activate" the grid-tie system.

Goal 3: I want to work up to Goal 1 and 2 incrementally.

The steps I think I need, please provide any input to this to correct me if I am wrong or if you know a better way.

1) I want have a professional electrician modify my panel box with a disconnect from grid power and whatever is needed to to run all needed lines out to my solar installation. The panels will be mounted on a pole building about 175ft from my house.

2) Once that is done I want to start with a single panel and single micro-inverter. I will probably buy a high quality pre-made panel to start with, but I want to build the rest of my panels and additional micro-inverters myself as I go and as money frees up.

This will be a "fun" project for me as much as a useful one... and I'm pretty handy. I have worked as a carpenter and electrician helper in my past and I'm an IT manager now, so I have all the fundamental understanding to do this. I just want to wind up with a nice system that works well but can be built incrementally and work completely off-grid if necessary but don't care about full time off grid usage, so I don't want the expense and mess of batteries unless it is possible to use only a few batteries to keep the grid tie system sensing voltage and not have to use the generator.

[Volusiano]

You'll most likely need to get permits for your grid-tied installation, from the utility company, the city, the HOA, etc. So it doesn't make sense to start with just 1 panel and 1 microinverter and go from there because each time you incrementally add on, you'll have to go through the whole permit process again.

It's probably best to start out with something significant enough each time to make the whole process worthwhile, like a 3 or 4 KW system. Then when you're ready to add on, simply add on another 3 or 4 KW system incrementally next.

With that said, you don't need to take the microinverter approach to do this kind of expansion either, unless you have shading issues or orientation issues. Just tie a 3 or 4 KW system to a string inverter. Then when you need to expand, duplicate the process.

[silverhorsefarm]

You can't trick GTIs

Goal 2: I want the system to be able to work off grid when needed. I already have a 6500 watt diesel generator that won't run the entire house so I'll be using the generator to provide voltage to "activate" the grid-tie system.

I've been assured that this will never, never, work. The inverters need sustained, clean grid power to wake up - a generator will not do that. Something about the grid's low impedance.

Otherwise, sounds like a plan!

[Volusiano]

Goal 2: I want the system to be able to work off grid when needed. I already have a 6500 watt diesel generator that won't run the entire house so I'll be using the generator to provide voltage to "activate" the grid-tie system.

Some newer string inverters like the SMA Sunnyboy 4000TL gives you an option to have a power outlet that you can plug in to get power from (assuming that it's during the day and the panels tied to it are producing) when the grid is down. This is probably the best/easiest option to be able to draw power from your panels when the grid is down.

[Sunking]

Goal 2: I want the system to be able to work off grid when needed. I already have a 6500 watt diesel generator that won't run the entire house so I'll be using the generator to provide voltage to "activate" the grid-tie system.

That is not going to happen. You can certainly install an ATS to have your generator operate when the grid is down, but you will never be able to have solar when the grid is down. Just not going to happen so get used to it.

Secondly very bad idea to do any of this incrementally. Permits and fees will eat you alive and take away any payback incentive.

[Wy_White_Wolf]

.... I will probably buy a high quality pre-made panel to start with, but I want to build the rest of my panels and additional micro-inverters myself as I go and as money frees up...

How are you going to get your DIY panels and inverters UL listed? Unless you live in a 3rd world country that will be a permit requirement.

With how low panels have dropped in price you can now buy panels for less than you can build them.

WWW

[getut]

You'll most likely need to get permits for your grid-tied installation, from the utility company, the city, the HOA, etc. So it doesn't make sense to start with just 1 panel and 1 microinverter and go from there because each time you incrementally add on, you'll have to go through the whole permit process again.

It's probably best to start out with something significant enough each time to make the whole process worthwhile, like a 3 or 4 KW system. Then when you're ready to add on, simply add on another 3 or 4 KW system incrementally next.

With that said, you don't need to take the microinverter approach to do this kind of expansion either, unless you have shading issues or orientation issues. Just tie a 3 or 4 KW system to a string inverter. Then when you need to expand, duplicate the process.

Unfortunately the money isn't there to do this anything other than incrementally. Also the WANT to do this all at once isn't there. I want to do this as a fun project for me. I'm willing to get an initial permit but will do the add ons with or without a permit. Besides, I don't even think it is possible to get a permit if I build my own panels which I will definitely be doing as I expand the system. I have a lot of libertarian in me.. I love doing things right, neatly and safely but couldn't care less about getting permission from government to do it. If my electrician and other knowledgeable eyes say its right, safe and neat it'll get done.

[Sunking]

Unfortunately the money isn't there to do this anything other than incrementally. Also the WANT to do this all at once isn't there. I want to do this as a fun project for me. I'm willing to get an initial permit but will do the add ons with or without a permit. Besides, I don't even think it is possible to get a permit if I build my own panels which I will definitely be doing as I expand the system. I have a lot of libertarian in me.. I love doing things right, neatly and safely but couldn't care less about getting permission from government to do it. If my electrician and other knowledgeable eyes say its right, safe and neat it'll get done.

Quit wasting our time. Without a permit or DIY system, no electric company in the USA will connect you. There is no way around it.

[Volusiano]

2) Once that is done I want to start with a single panel and single micro-inverter. I will probably buy a high quality pre-made panel to start with, but I want to build the rest of my panels and additional micro-inverters myself as I go and as money frees up.

If I can get a nickel for every time I hear a newbie say they will build their own panel (and this one is new -> build their own microinverter) like they know how to do so much cheaper than existing products in the market ...

If they already think they can build everything themselves for much cheaper, why bother calling themselves newbie and asking questions on this forum? They already think they're a genius.

[Wy_White_Wolf]

Unfortunately the money isn't there to do this anything other than incrementally. Also the WANT to do this all at once isn't there. I want to do this as a fun project for me. I'm willing to get an initial permit but will do the add ons with or without a permit. Besides, I don't even think it is possible to get a permit if I build my own panels which I will definitely be doing as I expand the system. I have a lot of libertarian in me.. I love doing things right, neatly and safely but couldn't care less about getting permission from government to do it. If my electrician and other knowledgeable eyes say its right, safe and neat it'll get done.

Would you like paying the power company for power you produce? or would you rather they credit you for that power to offset your dark hour usage?

Not all meters turn backwards and those that do are getting replaced with smartmeters that will tattle on you.

WWW

[SunEagle]

More than likely the Utility will detect that you have illegally connected to their grid and they will just shut off your power until you disconnect.

Then you can figure out how to build an off grid system to keep his lights on or just run your generator.

I know that sounds mean but there are safety rules that you need to follow and get permission no matter if you like it or not. You can't just decide to do things yourself and think you can get away with breaking the law.

[getut]

How are you going to get your DIY panels and inverters UL listed? Unless you live in a 3rd world country that will be a permit requirement.

With how low panels have dropped in price you can now buy panels for less than you can build them.

WWW

Let me explain better so some of you will understand, I fully understand about the hooking the system to the grid needing a permit etc. I plan to do the initial install with ALL UL listed equipment and get permits etc for everything that is done but only in the first phase. I also plan to have that initial install all done by my electrician on top of my pole building that I will be building in the spring. But that initial phase will be the most expensive. By the time my electrician modifies my panel and I get all my wiring out to the pole building, I won't have enough money left except to have max 2-3 panels and matching inverters installed in that initial pass.

But once I have the frame work in place and professionally done, I plan to build my own panels and use them with the same model micro-inverters that I start the project with. I never said I was going to build my own micro-inverters. I WILL build my own panels and expand the existing system by adding a panel and a microinverter every couple of months until my capacity reaches a point I am satisfied with it. That is the "fun" part of the project. Building the panels and expanding my system. This is the part that I simply will not ask the government for permission every time I add a panel or two.

So I'm trying to get advice from you guys on the specifics. It is important to me to do it right and safely. If it is cheaper to buy them I'd love to know. I don't mind buying the cheap panels from the Chinese market dumping them. Doing this incrementally will allow me to have a larger number of them in the end that I would have otherwise been able to do all at once, so if they start degrading at 10 years instead of 20 or only put out 90% of their rating it doesn't bother me. I'll just add more of them over time.

[SunEagle]

Let me explain better so some of you will understand, I fully understand about the hooking the system to the grid needing a permit etc. I plan to do the initial install with ALL UL listed equipment and get permits etc for everything that is done but only in the first phase. I also plan to have that initial install all done by my electrician on top of my pole building that I will be building in the spring. But that initial phase will be the most expensive. By the time my electrician modifies my panel and I get all my wiring out to the pole building, I won't have enough money left except to have max 2-3 panels and matching inverters installed in that initial pass.

But once I have the frame work in place and professionally done, I plan to build my own panels and use them with the same model micro-inverters that I start the project with. I never said I was going to build my own micro-inverters. I WILL build my own panels and expand the existing system by adding a panel and a microinverter every couple of months until my capacity reaches a point I am satisfied with it. That is the "fun" part of the project. Building the panels and expanding my system. This is the part that I simply will not ask the government for permission every time I add a panel or two.

So I'm trying to get advice from you guys on the specifics. It is important to me to do it right and safely. If it is cheaper to buy them I'd love to know. I don't mind buying the cheap panels from the Chinese market dumping them. Doing this incrementally will allow me to have a larger number of them in the end that I would have otherwise been able to do all at once, so if they start degrading at 10 years instead of 20 or only put out 90% of their rating it doesn't bother me. I'll just add more of them over time.

What you haven't considered is that the Utility will be confused when you start to generate more power then what was originally stated on your permit. Their net metering logs will see the increase going beyond what was installed. They will then come out to investigate and will find the additional panels you installed without getting their permission.

Now based on your Utility, they might not even care about the additional panels if they are UL listed and properly installed per Electric Code. But if they are not UL listed be prepared to get disconnected and probably penalized with a big fine.

[getut]

What you haven't considered is that the Utility will be confused when you start to generate more power then what was originally stated on your permit. Their net metering logs will see the increase going beyond what was installed. They will then come out to investigate and will find the additional panels you installed without getting their permission.

Now based on your Utility, they might not even care about the additional panels if they are UL listed and properly installed per Electric Code. But if they are not UL listed be prepared to get disconnected and probably penalized with a big fine.

If that is likely to be an issue, is there any way to use grid-tie and ensure it always supplements or possibly supplies up to 100% of a homes need without backfeeding the grid?

[SunEagle]

If that is likely to be an issue, is there any way to use grid-tie and ensure it always supplements or possibly supplies up to 100% of a homes need without backfeeding the grid?

First off you would "always" have to be using more power than your system generates. (That seems like a waste of energy to me).

But even if you do all it takes is for clouds to come over and the Utility will see wild power usage swings from very little being used when the sun is shining to a lot when it is not. Most homes don't consume power that way and it will probably send up a flag as being strange requiring investigating.

I believe you are trying to out think the Utility and in the end will probably cost you much more that getting a permit for each addition.

Just my thoughts but your decision to not comply with the rules is waste of your money and plain dumb.