Thinking about grid-tie

[bankscofarmer]

I have a large family and we've cut back on what we run, how run it and when we run it, electric-wise 

Needless to say, our utility bill is in need of SOME reduction. I've read enough and heard enough to realize that we will not be able to eliminate our electricity bill without spending at least $10k in panels and inverter...so I'm starting off small...getting a feel for the "otherpower" game.

Based on reading I've done here, it seems that my choices are pretty much limited to Outback GVFX series. I'm looking to get betwee 1 and 2 KW going in a combination of solar and wind - without breaking the bank.
I want to start by buying the inverter and getting it installed...then 2 220w pv panels every 3 months or so and finally a wind turbine in the 400w range way down the line.
I'm aiming small, I know - but it's a start, right.
Budget for the inverter would be around $1500 to $2000.

I'm looking for some recommendations based on the information provided. Can any certified electrician install this inverter? What pricing am I looking at for installation? Can I do it myself?

Thanks in advance!
BCF

[fabricator]

Hopefully one of the grid tie guys will come along, but if you want a grid tie sine wave inverter and you want to add panels as you can, I think your $2000 dollar inverter budget needs to be doubled.
Inverter installation is not rocket science, especially with all the excellent help you can get right here.

[ghurd]

"then 2 220w pv panels every 3 months or so"
Not a great idea!

220W panels are big.  As in too big for UPS.  Meaning they ship freight, on a skid.  Shipping a skid is Not cheap.
Call the dealer and ask for a S&H quote for 1, 2, 10, and for 20 panels.

I paid ~$400 to have a skid shipped ~50 miles.
(could not pick it up myself because it was in a customs clearing area)

Might look for a semi-local dealer.  He gets them on skids, and his S&H not so bad (per PV) because he gets them on full skids.
G-

[TomW]

"then 2 220w pv panels every 3 months or so"
Not a great idea!

220W panels are big.  As in too big for UPS.  Meaning they ship freight, on a skid.  Shipping a skid is Not cheap.

Plus they are a beach to handle without help. I find the smaller sizes to be much more handy to handle.

Plus what G mentioned about shipping.

4 75 watt and 4 130 watt units in this array:




The 130's are about as big as I would want to handle alone.

Tom

[ghurd]

"BIG" has issues.
Everything from the mounting to the stresses involved.

"BIG" gets 'A Lot Bigger' in real-life.
G-

(sorry, in the pic make the 80W a 75W)

[birdhouse]

maybe it's because i'm young (30) and dumb, an kinda out of control, but i find the bigger panels (200w) to be pretty easy to move around with just one guy, though it does take some thinking on what's the best way. 

i was able to get the rig below, which is 390 watts of evergreen panels on the roof with one other guy.  the steel mount was already made, so it was pushing the whole darn thing up there at once, but was do-able.  no one hurt, and no crashing panels.  though it was hard, and took some serious planning. 



adam 

[bankscofarmer]

Thanks for the advice on the panels guys. It was more or less a guideline. I can work with smaller panels as well...adds to redundancy too, I guess
I'm still young, have a strong back and a strong wife...hahaha. We've done things on the farm that we probably shouldn't have done - so I don't think the 220's will be a problem to handle, but it is definitely something to think about when working in areas that may not be able to handle that type of stress...our house is OLD! lol.

So $2000 isn't enough for a sine wave grid-tie inverter? Wow...this is going to take a bit more than I thought!

[DanG]

So $2000 isn't enough for a sine wave grid-tie inverter?

Building up the bulk-of-system incidentals eats good money, ie: to-code inverter mounting panel and junction boxes, accessible disconnect, meter housing, labeling, AC conduit & hardware and wiring, PV ground fault monitor, DC conduit & hardware and wiring, PV panel feed combiner box, earth ground strap & hardware and rod... And I'm quite sure I missed items.

[bankscofarmer]

Ouch...almost seems cheaper and easier to finance it and get someone to come and install it, right!

[TomW]

Ouch...almost seems cheaper and easier to finance it and get someone to come and install it, right!

That is dependent on your abilities, time available and financial resources.

I find I do less fully DIY stuff than I did when I was younger.

Sometimes it is just best to hire it done right.

I guess you will need to make that decision.

Or some combination of DIY and hired out.

Tom

[bankscofarmer]

Agreed!
I'm a DIY type person...we do a lot of things ourselves and learn a lot in the process. I'm feeling a little intimidated by this project though.

[TomW]

Like any big project, just break it down into manageable chunks.

Mount the Panels

Mount the Inverter

Install batteries.

Run Cabling.

Etc.

Not necessarily in this order but you get the idea.

Otherwise you will get overwhelmed.

Tom

[bankscofarmer]

Thanks Tom, that makes it a bit easier on the senses
Any recommendations on inverters? I'm reading through the posts here and I see a lot of information, but I'm having difficulty connecting the dots...

[B529]

Thanks Tom, that makes it a bit easier on the senses
Any recommendations on inverters? I'm reading through the posts here and I see a lot of information, but I'm having difficulty connecting the dots...

http://www.sma-america.com/en_US.html

I've installed a handful of SMA inverters.  Excellent product and customer service.

Adding a panel every so often to a grid-tied inverter is going to be a little tricky. Take a look at SMA string calculator on their website, you just can't add a single panel. You will mostly have to add a string of panels at a time.

When adding a string of panels in the future, best to stay with the same brand/model #, so don't buy any discounted/discontinued panels.

You need to do some homework for your location. Here in Colorado, as a homeowner you can install everything yourself w/o having to hire an Master electrician to pull a permit, check that stuff out by calling your state electrical inspector. If you have some basic electrical knowledge, a grid-tied solar system is very EZ. You will obviously have to follow your state electrical code. Also contact your local utility provider to see what they require (where to put disconnects, to you have to buy a grid-tied meter....), not all utility providers are grid-tie friendly. Some municipality will require you to have a permit to put up a rack and supply engineered drawings of the rack for loading (most rack manufacturers will supply that info) , check that as well. If you are going to install it yourself, buy or borrow a current electrical code book and educate yourself.

Also maybe consider getting/installing a rack now that will accommodate the total  number of panels you want to end up with.

[TomW]

I am sold on Outback equipment.

Not cheap but when my FX2524 inverter got killed by lightning They sent the repair boards. There was a problem with their shipping dept. not getting it out as fast as they normally would which they handled professionally and quickly. They refunded the board fees because of the shipping issue which was more than fair.

Bottom line was my out of warranty inverter was repaired by me with boards from Outback.  The board kit was not very much like $300 or something for all the boards in the unit.

They also traded  my Mate accessory for a new one free when it also was probably killed by a lightning strike.

I probably will not buy any other brand because they have proven themselves willing to go above and beyond what was required in customer service after the sale and out of warranty too boot!

That means a LOT to me.

You won't get that from the average cheapie inverter company.

The inverter was like $1700 new and the Mate was a couple hundred plus I forget exactly.

Just from here, if it matters.

Tom

[bankscofarmer]

Thanks for the feedback. I'm considering my options...this is a little more involved than I initially thought.

[ChrisOlson]

Based on reading I've done here, it seems that my choices are pretty much limited to Outback GVFX series.

Your choices are certainly not limited to the GVFX.  Schneider Electric (SquareD) also has UL1741 grid-tie inverters available under the Xantrex brand name.  They are 120/240 split phase out of the box with no need to stack inverters.  The are also more expensive but by the time you buy two 120 volt units to stack them for 240 the XW-series Xantrex will probably come in a little less money.
--
Chris

[Rob Beckers]

Bankscofarmer, are you looking to be off-grid at some point, or have battery backup for when the power goes out? If that is not in the planning and your aim is strictly to reduce your electrical bill then regular grid-tie without batteries would be the easier and cheaper way to go. I'm a bit confused because your title has "grid-tie" while you mention planning on Outback inverters, which are meant for off-grid use (though they can be grid-tied and have a sell-back engine, it just adds lots of expense and additional losses for batteries).

As to panels, for a couple kW truck freight is not bad, and a minor part of the expense. We generally install modules in the 200 - 250 Watt range as the trade-off between ease of handling vs. work/cost involved in dealing with many more smaller panels. The 200W's are easy enough to be carried by one person, the 250W's are a little heavier but still perfectly doable, even for my 47-year old carcass with a bad back. For actual installation on a roof, or any height, you should have a second person to carry/hold the panel, it's just a 2-man job even for the smaller stuff.

As to inverters, for battery based ones I like the Xantrex XW's more than Outback. Especially for someone new to inverters (they're much easier to set up). For grid-tie we use Power-One Auroras (that's without batteries). Anyone reasonably handy can install and wire up PV and inverters, I've talked a number of people through that process (an honest evaluation of your abilities is of course in order). One question is though if your jurisdiction allows electrical work by home owners, or if it can only be done by an electrician (this varies from place to place).

-RoB-

[bankscofarmer]

First off, thank you to everyone that contributed to this thread. It is certainly a learning experience!!!

RoB,
Thanks for the information. The terminology is still a bit new to me...so I should clarify. The current goal is purely grid attached - no batteries yet. I have not had a power outage here in the last 2 years and that included one of the worst snow storms we've had for some time. I use wood for heating, so it is not a matter of life and death if I have to run off a genny for a few hours
I'm fairly handy...installed the electric water heater and stove (see why I can't go to batts hehehe) and had to run the wires and wire them into the panel...I can figure it out with enough instructions and I have all the tools needed for that job.
I'm not sure about the legalities involved...not really strict here...I asked the inspector about offgrid electricity and he said "as long as it is per manufacturers' specs, you are good to go". I also have a buddy that's an electrician, so I can get him to help out.

Thanks again for the help!

[ChrisOlson]

As to inverters, for battery based ones I like the Xantrex XW's more than Outback. Especially for someone new to inverters (they're much easier to set up). For grid-tie we use Power-One Auroras (that's without batteries)

Rob, it might not hurt to explain these options a little more since bankscofarmer may not realize they exist.

For instance, there are advantages and disadvantages to both with a grid-tied system.  With a battery based inverter that sells power to the grid, such as the XW, your house can stay powered up during utility failures.  Most non-battery systems cannot do this.  And advanced inverters like the XW have modes they can run in where the inverter uses grid power during off-peak times and runs your house on batteries during peak load times, called Peak Load Shaving.

And during the times when the inverter is using grid power it can be configured to directly use power input from RE sources before it uses utility power without going thru the losses in involved in battery charging.  In this mode you can use a small battery bank that is only there for brief power outages to keep your power on and the batteries otherwise "float".  If the "float" setting is exceeded due to input from RE power sources, the inverter will directly use that first and cut back on the amount of power it's drawing from the grid to run the loads.

There are many, many options depending on what sort of system you would like to have.  And that makes a big difference on what sort of equipment you will need.  In many cases selling power to the utility is not all its cracked up to be because of the additional equipment and red-tape required to do it (customer-supplied outdoor disconnect, net meter agreements, etc..).  And most utilities will never pay you for any excess power you generate.  Only provide a credit on your bill which you have a certain amount of time to use up.  If you don't use the credit in the allotted time you lose it and the utility gets free power at your expense.

So in most cases I've found that it's better to use your system to power your own loads and cut back on the amount of power used from the utility, and forget about grid-tie.  The only time I've ever really seen grid-tie pay off is if there are tax and/or price incentives, such as Canadian hydro customers getting paid something like .84 cents/kWh for roof-mounted solar and .52 cents (or whatever it is) for ground-mounted solar.

So there are many, many options.  And it is most times more complicated that simply throwing in an inverter and solar panels and wiring it all up.  A carefully designed and planned-out system that uses Peak Load Shaving, for instance, where the inverter limits utility power draw during Peak Load times, and fills in the excess need from the batteries, then "catches up" later during off-peak hours may save you money in the long run by eliminating peak load surcharges.  This is just an example of a system that would NOT be grid-tied.  This system requires that all the loads go thru the inverter in order to be effective.

A poorly planned-out system, OTOH, where you just throw in a grid-tied inverter without doing the research on how you are billed by your utility may end up costing you more money in the long run because you'll never pay for your equipment with the availability of artificially "cheap" grid power.

That's just some of my rambling thoughts on it.
--
Chris

[MaxtorD]

Might want to check out this Guy's Grid-Tie Outback install.   

His YouTube Videos of his install...
http://www.youtube.com/user/srockriver

His install website....
http://www.rockriver.us/


I found his site very informative and he answered all the questions I had for him through email.   A Great guy. 
-MD

[ChrisOlson]

Might want to check out this Guy's Grid-Tie Outback install.

After listening to his description of just one person getting screwed on a net-metering agreement all I can say is that I'm glad I'm not even hooked to the grid.
--
Chris

[ghurd]

Might want to check out this Guy's Grid-Tie Outback install.   

A Great guy. 
-MD

Some of those photos look very familiar.   Is he a FL member?

'Vista' is mad at me again, and the videos would not play.
G-

[MaxtorD]

He was a member of the old board and had a BAD experience with net metering.   He said he was happy with his RE system and it's performance, just not happy with the power company. 

[stgctaylor]

Rob, I have read through a lot of your posts and responses and I think that you can answer a question for me. Granted, I am a "newbie" to homebrew Electricity, but I am in the process of building my first wind unit. It isn't very advanced, I'm using the treadmill motor method, and what I want to do is tie in to my home grid. As my knowledge increases, I want to progressively increase the productivity of my wind units, and also get to solar power as well. For now, my question is: If i am not using batteries, and i want to just tie in to the grid, do I need a controller for my unit? I have a 400w inverter, and i want to connect my unit to it, by way of a diode, a fuse, and a manual disconnect switch. Is this something that can be done?

[ghurd]

For now, my question is: If i am not using batteries, and i want to just tie in to the grid, do I need a controller for my unit? I have a 400w inverter, and i want to connect my unit to it, by way of a diode, a fuse, and a manual disconnect switch. Is this something that can be done?

What does the inverter manual say about it?
If it does NOT clearly explain how to do it, then it can't be done with what you have.

Grid tie takes special stuff.
G-

[stgctaylor]

ghurd, thanks. My main question is whether I need a controller if i am planning on using the power direct and no charge batteries with it.

[ghurd]

What does the manual say about it?

A grid tie inverter can be designed for use with or without batteries, it may or may not have a voltage clipper in it, and it may or may not regulate the battery if one is used.

The point was, if you are asking what it needs, and it is not explained how to connect it in the manual, then the inverter is not suited to grid tie regardless of batteries and controller or not.

You are looking for something like this-
http://www.sma-america.com/en_US/products/wind-power-inverters.html

[ChrisOlson]

The point was, if you are asking what it needs, and it is not explained how to connect it in the manual, then the inverter is not suited to grid tie regardless of batteries and controller or not.

Indeed.  To tie in to your home grid-connected electrical system with an RE source, without charging batteries, requires an inverter that meets certain requirements (UL1741 in the US).  Most times an agreement is required with your electric utility as well, and the installation of a lockable disconnect switch, accessible by utility personnel 24 hours a day, is required so your system can be disconnected/shut down by the utility if deemed necessary for whatever reason.

It's a little more complicated than just needing a controller.

There's a selection of cheap non-UL Listed Chinese built "grid tie" inverters that "tie" to the grid by plugging into an electrical outlet in your home.  Using one of those opens a can of worms with everybody from your insurance company to possible backfeed to the grid if the grid goes down, and being sued into oblivion by the utility if they find out you got it (or you kill a lineman with one).  I won't name any brands, but if you happen to see one of these, don't even consider it.
--
Chris

[stgctaylor]

So I guess what you are saying is that my best bet for my homebrew energy would be off-grid. Really what i want to do is eventually generate enough energy to run some of my heavy consuminging appliances, mainly, my air conditioning. My house stays pretty cool until mid afternoon, then I have to run the A/C. I live in north Texas and we have both sun and wind in abundance and I really want to try and utilize these natural resourses. Since I am new to this, i am open to any and all suggestions as to the route I should go with this. I am not well off so money is always an issue, and that is the main reason I am looking to alternate energy, but I like to do things myself also, so this particular thing appeals to me on multiple levels.

[Rob Beckers]

stgctaylor, I've not read every word of this thread so this may be double: For grid-tie of wind turbines (I understand you're building your own), you need a UL listed grid-tie inverter specifically made for wind turbines. Your existing inverter won't do that. The only brands I know to make these are the SMA's WindyBoy, Power-One's Aurora, and possibly Ginlong's inverter (not sure if they have UL listing yet). By and large it is a little bit harder to make a grid-tie wind turbine vs. off-grid, because the battery chargers always have a load. For a grid-tie turbine you have to make sure it never overspeeds,  and you never present too high a voltage to the inverter. The voltage for grid-tie turbines needs to be higher as well; 250 - 300V 3-phase AC from the alternator is a good value to shoot for. Grid-tie inverters are not cheap, but neither are batteries. Lastly, offsetting your current electricity use through a grid-tied wind turbine is a tough job (for most people). It's only when you start making your own electricity that one gets an appreciation for just how much most of us use (and I'm no exception either).

-RoB-

[stgctaylor]

Thanks for the helpful facts. I think for now I am going to build my turbine and test it and work with it to see how productive I can make it. I am aslo going to purchase a controller kit from ghurd, I have been reading through his posts and managed to find his website. I will be going the direction of a bank of batteries, and running my current inverter from those, just to get a good feel for what I am doing. I am still planning to eventually try to offset my utility bill, whether it's grid-tied, or not. On average I am using about 850 Kwh a month and I know that any energy I generate won't come anywhere near that, that is why I was trying to find out about being grid-tied, just to bring that total down a little at first, and then a little more as my knowledge grows with the addition of a better turbine and some pv panels. I am starting to get the idea that a grid tie system is farther down the road than I had initally expected.
I am still excited about the prospect of building my own turbine and seeing what I can do with it. I appreciate your patience with this "newbie"!

[wdyasq]

So I guess what you are saying is that my best bet for my homebrew energy would be off-grid. Really what i want to do is eventually generate enough energy to run some of my heavy consuminging appliances, mainly, my air conditioning. My house stays pretty cool until mid afternoon, then I have to run the A/C. I live in north Texas and we have both sun and wind in abundance and I really want to try and utilize these natural resourses. Since I am new to this, i am open to any and all suggestions as to the route I should go with this. I am not well off so money is always an issue, and that is the main reason I am looking to alternate energy, but I like to do things myself also, so this particular thing appeals to me on multiple levels.

I live about 50 miles SW of Fort Worth. As I live in a 'town', I am not permitted a wind turbine. I am installing ~3kW of PV. I am also going to install a small battery bank and 'grid-tie', although I would rather be off-grid, it just isn't economically viable with a power poles in my yard.

AND, speaking of economically viable, going RE isn't at this time. I use less electricity than most but still, a large (IMO) amount. My bills average ~$80 month with $0.15kWh costs by the time it gets here and gets billed. For what will be a $10k or more investment, I'll cut my bill a lot. I will not be able to lower the charge for attachment to the grid and I will not get decent pay for any excess electricity I send to my lovely utility provider.

Some of the various expenses I can't get around.

"Smart Meter" - required so I can legally tie to the grid - ~$500
"Inverter" - ~$1800
"Charge Controller" - ~$800
"Batteries";  8 X "Golf Cart" - ~$300
"Electrical Parts"; DC combiner, crimper, connectors, boxes, disconnect, ground fault device and wire - ~$500


These costs are just educated guesses and DON'T include 'professional installation'.

With this system, I will be able to supply my own single phase 120V power for a short time and use up to 3kW of of power 'when the sun shines'. It is not enough battery to power an air-conditioner overnight. But it is enough to keep my freezer running and my beer cold.

Grid power is one of our American "bargains". It is inexpensive because of the enormous subsidization by industry and  politicians keeping the "apparent costs" to the voting public low by making it an incidental cost of every product we buy.

From a Don Marquis poem:

"it must be the same way
with a colored man who is being lynched
he must be grateful that he is being lynched
in a land of freedom and liberty
and not in any of the old world countries
of darkness and oppression
where men are still the victims
of kings iniquity and constipation"

Ron