A quick question regarding a small grid tie.

[Philliplee]

Hi,
I represent a group of students looking for some clarification on a small prototype grid tie installation. Our current setup involves a solar panel, and inverter, and some not fancy wiring. Before we try it we wanted to get some feedback on whether this is safe or not to plug in.

A more detailed overview is this:
A solar panel that is connected directly to an inverter (this one), which in turn is plugged directly into a standard wall socket.

This hasn't been done yet, we a looking for someone to double check us and let us know if it would or or if we're missing something.

By saying directly in the definition I mean a direct electrical connection to the specified item.

Thanks to anyone who reads and offers some assistance!

[russ]

Those things are junk and not legal - certainly not in the US.

Maybe K for a boat anchor or to throw at the neighbor's dof I suppose.

[Philliplee]

I appreciate your review, but this only has to work for just around 20 minutes or so. It's more proof of concept than something that would have a more permanent installation.

[russ]

I appreciate your review, but this only has to work for just around 20 minutes or so. It's more proof of concept than something that would have a more permanent installation.

Proof of concept of what? Nothing. Microinverters are sold that are legal and fine - UL listed, tested, safe and on and on. The crap shown on ebay should not be used on your dog's house.

The "plug into an existing" wall plug types go against code, are not UL (or equivalent) listed and go against all electrical safety considerations - not to mention can not be used in a grid tie as your utility will not accept them and homeowners insurance does not have to cover any electrical item not UL listed.

I will allow the link to stand for now so others can see the junk and comment - if I see a new link you will be banned.

[SunEagle]

Any of those inverters that can plug into a wall receptacle are not safe as well as being non UL approved. They do not have the proper fuse protection and they have a very high possibility of causing an electrical fire by overload your house wiring.

In the US if that item was determine as the cause of a house fire the homeowners Insurance company would void any policies and you would get nothing.

For yours and your families sake do not use it.

[Philliplee]

Proof of concept of what? Nothing. Microinverters are sold that are legal and fine - UL listed, tested, safe and on and on. The crap shown on ebay should not be used on your dog's house.

The "plug into an existing" wall plug types go against code, are not UL (or equivalent) listed and go against all electrical safety considerations - not to mention can not be used in a grid tie as your utility will not accept them and homeowners insurance does not have to cover any electrical item not UL listed.

I will allow the link to stand for now so others can see the junk and comment - if I see a new link you will be banned.

Yikes. This may have escalated rather quickly, I certainly hope that I haven't broken the forums rules, or offended you in any way. If I have, I apologize and had no intentions. Maybe a broader picture will help this topic out.
I'm part of a team who, as a school assignment, were asked to come up with an idea and build a prototype. Our general prototype involves a solar panel providing electricity back into the grid. We're on very tight budgets and are attempting to have this portion of our project functional (as hopefully the entire thing as well!) It doesn't have to last long and we don't expect on keeping it running, we just want it to safely work. As we are quite unfamiliar with this process, we thought it be best for us to query those more understand for suggestions that consider our circumstances. Ultimately, we're just looking for some reassurance that what we have will work.

[russ]

One big problem with much of the cheap junk sold on fleabay is that the seller knows full well they are selling illegal junk - therefore they put little effort into design or components. When there is a problem you find the seller has disappeared into some village in rural China or similar - no one to hold responsible.

It there is a solar dealer in the area they may let you borrow an inverter?

The grid tie is even more problematic - to do it correctly is important. There are permits and the OK of the utility to be obtained. Back feeding a circuit through a wall plug is a big no-no.

Maybe someone can suggest a way you can accomplish what you want in a safe and legal fashion. Your teacher should not be going along with this back feeding concept.

[FloridaSun]

I'm part of a team who, as a school assignment, were asked to come up with an idea and build a prototype.

maybe you would learn more to DESIGN a system on paper instead of buying a few parts, plugging them together, and thinking that is a 'build'. Sounds like you are looking for an easy way out of your assigned project.

[SunEagle]

Proof of concept

If your goal is to determine how solar energy can be used to provide power to the grid then I would say you are trying to re-invent the wheel. It is already being done.

If you are looking to come up with a new type of design with minimal number of inexpensive parts then you are under estimating what it will take to accomplish this effort. Connecting a solar PV system into the "grid" is not cheap and requires a number of rules and regulations that must be met before you can provide any power. The equipment is not cheap and must be UL approved. You can't just slap a few eBay items together to get a system working and then think you can just enlarge the system by making everything bigger.

There is a lot of info on this site that will lead you to the proper equipment and learn how to size it depending on how much power you want to generate.

There is also info on "Off grid" systems which can be relatively inexpensive as long as you don't add any batteries.

So exactly what are you and your Team trying to accomplish and how much power did you want to generate?

[green]

The other part to this equation is that you should not be displaying this dangerous illegal equipment to other impressionable students. It should not be presented as a safe option for going solar.As everyone here has already stated, grid tieing is a complicated very regulated thing. Just go to your local electric companies website and look up "electrical cogeneration" or "solar interconnection" and you will see what we mean.

Maybe what you could do for your school project is a solar off grid application.

[Philliplee]

In general, the basic idea is to power a light with a shared power supply between solar and grid electricity. I'll continue to browse the forums for suggestions or clarification on some questions I have, but again, I am grateful for the feedback.

Sounds like you are looking for an easy way out of your assigned project.

Perhaps this feeling is one sided, but the reception I've receive here has been less than welcoming. I appreciate the feedback but the phrasing has been rather rude, I hope this isn't typically how interested new members are treated.

[FloridaSun]

In general, the basic idea is to power a light with a shared power supply between solar and grid electricity. I'll continue to browse the forums for suggestions or clarification on some questions I have, but again, I am grateful for the feedback.
Perhaps this feeling is one sided, but the reception I've receive here has been less than welcoming. I appreciate the feedback but the phrasing has been rather rude, I hope this isn't typically how interested new members are treated.

New members that have unrealistic expectations usually are treated bluntly with the truth. Can be received as a demeaning manner but if you read many of the past posts my newcomers you'll see so many have pie in the sky dreams of 'free' power and it can get tedious in replies. 'Free' power? .... doesn't work that way. Maybe your instructor needs to be educated in the reality of solar power, the financial efficiency and what it costs to have a grid tie system with battery back up.
An actual small model battery system with good understanding of costs involved, a plan with cost analyses, of what it takes to safely connect to grid power might be a better route to take. Who is providing the finances for this project? Does your instructor approve of doing unsafe practices?
This forum is concerned with those who want to safely construct a PV system for various reasons. I hope that never changes.

[Philliplee]

New members that have unrealistic expectations usually are treated bluntly with the truth. Can be received as a demeaning manner but if you read many of the past posts my newcomers you'll see so many have pie in the sky dreams of 'free' power and it can get tedious in replies. 'Free' power? .... doesn't work that way. Maybe your instructor needs to be educated in the reality of solar power, the financial efficiency and what it costs to have a grid tie system with battery back up.
An actual small model battery system with good understanding of costs involved, a plan with cost analyses, of what it takes to safely connect to grid power might be a better route to take. Who is providing the finances for this project? Does your instructor approve of doing unsafe practices?
This forum is concerned with those who want to safely construct a PV system for various reasons. I hope that never changes.

I'm not certain about the unrealistic expectations, I'm politely asking for assistance in designing a setup for a basic, one time use, grid tie system. I'm also not too sure about where this "free power" topic came about but certainly have a realistic expectation of what is possible. We are students, the funding is what we're able to come up with. Our doctor is assisting us in regards of safety, however we are to design and build it on our own. I hope this forum does place safety over all things, as I say "Safety first, then teamwork." I understand these can be dangerous, which is why we are asking for help. Please, we are trying to work towards a solution.

[SunEagle]

I'm not certain about the unrealistic expectations, I'm politely asking for assistance in designing a setup for a basic, one time use, grid tie system. I'm also not too sure about where this "free power" topic came about but certainly have a realistic expectation of what is possible. We are students, the funding is what we're able to come up with. Our doctor is assisting us in regards of safety, however we are to design and build it on our own. I hope this forum does place safety over all things, as I say "Safety first, then teamwork." I understand these can be dangerous, which is why we are asking for help. Please, we are trying to work towards a solution.

I understand. Then maybe you should start with using the accepted and safely designed "grid tie" inverters.

There are quite a few that range in their ability, size and cost. The Manufacturers are to name a few; Xantrex, SunnyBoy, Outback, Enphase, Power One.

You would match them to the size and output specification of the solar panels array which consists of the voltage and amperage the panel or panels output at peak sun exposure.

Since most "grid tie" system are not small, the Inverters mentioned above are sized for about 2000 watts and up. Usually it isn't worth installing a smaller system because the cost per kw goes way up. A medium to large system will get you a lower cost per kw which is usually more affordable.

[FloridaSun]

I'm not certain about the unrealistic expectations, I'm politely asking for assistance in designing a setup for a basic, one time use, grid tie system. I'm also not too sure about where this "free power" topic came about but certainly have a realistic expectation of what is possible. We are students, the funding is what we're able to come up with. Our doctor is assisting us in regards of safety, however we are to design and build it on our own. I hope this forum does place safety over all things, as I say "Safety first, then teamwork." I understand these can be dangerous, which is why we are asking for help. Please, we are trying to work towards a solution.

What course does this involve? How much are you expected to design and build? Hopefully your instructor expects more from you than just buying a few parts on ebay and plugging them together. Have you taken the time to understand how a PV system works?

somehow I get the impression your doctor has not understood the expense of prescribing you this treatment for a 'one time' display. You're going to spend $179 on an illegal inverter and then... what?... throw it away? Not likely, more likely someone will continue using it.