Tying into the grid

[tcrenshaw]

I know that I'll most likely need a licensed electrician to tie my solar panels into my home electrical panel but is there a website or can someone tell me exactly how this is done? I know I don't just add in an inverter and connect up to the 120v bar in my electrical panel. So how is this done exactly? I would really love to see my power meter run backwards one day.

[iFred]

Download the newest book (in  PDF) from Homepower mag available now!

www.homepower.com

Has total discriptions..

P.S. you have to register to download, but every 2 months a new issue (about 13megs worth) is available and very good reading on both solar and wind.

[troy]

Yes, I totally agree with Fred.

www.homepower.com

is a great resource with lots of diagrams, schematics, overviews, sage advice, many excellent vendors etc.  It's free.  Why not go for it?!

The short (incomplete) answer is that you need a grid tie inverter.  There are exactly zero cheap grid tie inverters. If you hook a normal (non-grid tie) inverter to your breaker panel (ie the grid) something will blow up and if you're lucky you'll get a fire too. You'll also have to do a song and dance for your utility.  Some make the process straightforward, most make it difficult/expensive.

Good luck and have fun!

troy

[tcrenshaw]

Thanks for the info on the electronic magazine, I'll go check that out. Also thanks for the info on the grid tie in inverter. I also had one other chap send me information directly and he's gone into some great detail on how this is all done. I've also sent off a nice email to my power company (TXU) to find out what their requirements are. I'm sure they have received the email and some flunky is going "what do I do with this?" and hasn't a clue. We'll see if they are going to be nice about it or not. Would be great to get a letter back stating they don't allow or support it. I'm sure some of the news chanels may be interested in that since TXU is always claiming how they want to help the consumer with their power needs. I think it's more they want help the consumer but only if it helps line their pockets. I don't blame them for that, they are a business, but they also need to provide the consumer with the freedom and options to do their own thing. Hopefully they will be one of the less difficult/expensive type power companies.

Thanks again,

Todd

[RC in FL]

Also read articles on Trace SW series that can grid tie.

You must be sinewave inverter, have the ability to sync to grid phase and control push into grid.  

I have SW4048's, for backup power purpose so I am not interested in pushing into grid but I had to try it out just once to see my power meter wheel run backwards.

[tcrenshaw]

I would love to see my meter go backwards but after reviewing my plans and goals I'm going to have to pass on a grid tie in system and go with an isolated system first. Eventually the plan is to be completely off the grid. I was looking tying into the grid if the expense wasn't that much different from a standard pure sign wave inverter. That's not the case though so it doesn't make sense for me to spend the extra cash for a grid tie in inverter. Bummer kind of. It would have been fun to see the meter run backwards.

[troy]

You'll never really make a profit on grid tie unless someone is subsidizing your alt energy system (ie california).  But economics isn't everything.  The weak link in most AE systems is the battery bank.  Expensive, dirty, dangerous, fussy (need correct temp, pure water, reg maint., an enclosure, etc).  There are some real advantages to having a batteryless grid tie system:

1. You're doing your part to save the planet.
   
2. It's fun to spin your meter backwards and stick it to the utility.
   
3. Low low maint. issues.  Once it's set up, you just watch pretty much.
   
4. Indefinite life span.  Batteries absolutely die. Cheap ones die fast, expensive ones die slow.  Without batteries, it's realistic to think you might go a decade with no real problems with your system.
   
   

Of course, the down side is when the utility goes down, you go down to.  And you have to play nice with the utility or they won't let you participate.

Good luck and have fun!

troy

[skravlinge]

To supply everything at home it is common here to attach the power just after the meter. You have to get grid-quality which here is 220 v 50 hz. If you not have a lot surplus its noworth to sell back. Living at the grid is often cheaper (if you try to conserve the use ) than have diesel backup. Its easier to buy equipment for the grid rate, than using 12,24,or 48 volt. A production of  a few kilowatt can reduce the bill a lot as you buy from grid just the peak and produce that you steady use yourself. No battery and worries, it goes without attention.It can easy be more than half the bill.

[tcrenshaw]

I like 1., 2., and 3 big time Troy. As far as my utility company (TXU) I sent them an email about three weeks ago. They responded with, we've forwarded your email to the appropriate department. I haven't heard word one. Since then I've decided not to tie into the grid but instead remove one room from the house at a time and move it over to the home power system.

[juiced]

There are several compiled lists of the exact people and departments to contact.