Mostly new to solar and seeking advice

[ButchDeal]

Is there a way to set up a system where the batteries are missing or minimal, you pull power from the panels when they are producing but the grid when you need the extra? BUT not a true grid tied system where I back feed onto the grid? (That requires a 7 year contract here with some details I don't like, so would never agree too)

Yes the outback system is capable of doing this. They call it Grid Zero and is just a setting on their systems.

https://www.youtube.com/watch?v=a33p0jbi1R0

http://www.businesswire.com/news/home/20140227005364/en/OutBack-Power-Unveils-GridZero-Energy-Balancing-Advanced#.VDfjt9R4qUA

[Sunking]

What does this look like? Got a link?

You would be looking for about 24 to 30 of these batteries. They cost around $1100 to $1200 each plus shipping and weigh around 300 pounds each.


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[SunEagle]

Yes the outback system is capable of doing this. They call it Grid Zero and is just a setting on their systems.

https://www.youtube.com/watch?v=a33p0jbi1R0

http://www.businesswire.com/news/hom...d#.VDfjt9R4qUA

Be careful. While Outback now has a small battery system that can be used for energy storage I still believe that system will be considered a Grid Tie system and will require the same approvals and contracts with the Utility as one without the battery system.

Sixfold

You need to do some research to see if your Utility will accept that type of system without having a 7 yr contract even if it is programed not to send power onto the grid but can accept power from it.

[mapmaker]

You need to do some research to see if your Utility will accept that type of system without having a 7 yr contract even if it is programed not to send power onto the grid but can accept power from it.

Why is it any of their business? Back when I lived on grid, it never occurred to me that I should ask permission to plug in my toaster which, like the grid zero, could accept power from the grid, but was configured not to sell power to the grid.

--mapmaker

[russ]

Back when I lived on grid, it never occurred to me that I should ask permission to plug in my toaster

Quite the toaster if it could export power to the grid!

[SunEagle]

Why is it any of their business? Back when I lived on grid, it never occurred to me that I should ask permission to plug in my toaster which, like the grid zero, could accept power from the grid, but was configured not to sell power to the grid.

--mapmaker

It might not matter and then again if they find that unit connected to the main panel which has the possibility of back-feeding the grid they might get upset and turn off your power.

The diagram for "AC Coupling" for the Outback unit shows power going both ways. From the grid and to the grid. That tells me the hardware can be configured for Net-metering or not. The Utility may want some guarantees that you can't put power back onto "THEIR" grid. If so then working with the Utility may be a safer way to go.

[J.P.M.]

It might not matter and then again if they find that unit connected to the main panel which has the possibility of back-feeding the grid they might get upset and turn off your power.

The diagram for "AC Coupling" for the Outback unit shows power going both ways. From the grid and to the grid. That tells me the hardware can be configured for Net-metering or not. The Utility may want some guarantees that you can't put power back onto "THEIR" grid. If so then working with the Utility may be a safer way to go.

I'd call them and ask a hypothetical question about equipment requiring the POCO's knowledge and agreement. They have you by the short & curleys one way or the other. Where's the harm ? They'll know one way or the other soon enough.

[SunEagle]

I'd call them and ask a hypothetical question about equipment requiring the POCO's knowledge and agreement. They have you by the short & curleys one way or the other. Where's the harm ? They'll know one way or the other soon enough.

Or you can play the "dumb" card and install the equipment without telling them because you hate to deal with the POCO and it isn't any of their business anyway what you do on your land.

[Sixfold]

it isn't any of their business anyway what you do on your land.

I'm more of this school of thought. If I'm not feeding into their equipment, they have no say in what I do.



I really like this Radian Series GS8048A. Its a bit pricy but it does alot in that one box. Looks like I could drastically reduce the size of my battery bank.



So:

Grid tie: ~$11k
8kw Solar Array: ~$8k
GS8048A: ~$4.5k
MPPT CC x2: ~$1.1k
Mini 48v battery bank: ~$2k
10kw Diesel Genny: ~$5k

Total ~31.6k + associated wiring and other misc parts.

That's much more in my budget. Although that 11k for the ability to pay for electricity seems like a kick in the teeth.

You would be looking for about 24 to 30 of these batteries.

48v @ 2430AmpHours would be 116640 WattHours worth of power. Would I really need that much to last me 2 days?!

[SunEagle]

I'm more of this school of thought. If I'm not feeding into their equipment, they have no say in what I do.

I really like this Radian Series GS8048A. Its a bit pricy but it does alot in that one box. Looks like I could drastically reduce the size of my battery bank.

So:

Grid tie: ~$11k
8kw Solar Array: ~$8k
GS8048A: ~$4.5k
MPPT CC x2: ~$1.1k
Mini 48v battery bank: ~$2k
10kw Diesel Genny: ~$5k

Total ~31.6k + associated wiring and other misc parts.

That's much more in my budget. Although that 11k for the ability to pay for electricity seems like a kick in the teeth.

48v @ 2430AmpHours would be 116640 WattHours worth of power. Would I really need that much to last me 2 days?!

If you are totally off grid then it doesn't matter what the POCO thinks or does. But if you connect to "their" grid and can generate your own power then you have to have equipment that will totally isolate your generation from theirs or is compatible and can synchronize with the grid. And that equipment is usually determined by the POCO and not the customer. The reason is for safety regulations that the POCO has to meet no matter how much of an inconvenience it is to the customer.

Using the POCO as your "battery" with a grid tie system will be less costly than using your own battery. If you are concerned about costs and you need emergency power for your home then a battery is the last source you should go to. A properly sized generator will just about always cost less as a back up power source.

Well a 116.6kWh battery system is not really that big if you use 25kWh a day. Most battery systems are designed for 4 to 5 days not 2 days. Over discharging is not good for the batteries and since things happen and with storms and snow you may be without sunshine for a longer period of time. That means running the gen set longer and harder or living in the dark. If you want a smaller battery system then figure on using much less kWh per day and size your battery for 4 to 5 times that daily usage. Or figure replacing those batteries in 2 years instead of the 5 you may get out of them by not abusing them.

[Sixfold]

If you are totally off grid then it doesn't matter what the POCO thinks or does. But if you connect to "their" grid and can generate your own power then you have to have equipment that will totally isolate your generation from theirs or is compatible and can synchronize with the grid. And that equipment is usually determined by the POCO and not the customer. The reason is for safety regulations that the POCO has to meet no matter how much of an inconvenience it is to the customer.

Using the POCO as your "battery" with a grid tie system will be less costly than using your own battery. If you are concerned about costs and you need emergency power for your home then a battery is the last source you should go to. A properly sized generator will just about always cost less as a back up power source.

Well a 116.6kWh battery system is not really that big if you use 25kWh a day. Most battery systems are designed for 4 to 5 days not 2 days. Over discharging is not good for the batteries and since things happen and with storms and snow you may be without sunshine for a longer period of time. That means running the gen set longer and harder or living in the dark. If you want a smaller battery system then figure on using much less kWh per day and size your battery for 4 to 5 times that daily usage. Or figure replacing those batteries in 2 years instead of the 5 you may get out of them by not abusing them.

OK thanks!

I think the key here will just be to increase my methods of power generation. Adding wind and micro-hydro to my solar and generator should take some of the strain off the battery bank size.

But you have convinced me that grid tie is the way to go.

[russ]

I'm more of this school of thought. If I'm not feeding into their equipment, they have no say in what I do.

If you get caught you also have no say in what they do - such as cut you off - the 11K powerline connection would be a bit of a waste then.

[Sixfold]

If you get caught you also have no say in what they do - such as cut you off - the 11K powerline connection would be a bit of a waste then.

Yeah good point. I'm sure they wouldn't mess around if they thought there was risk of a lineman being in danger.

[russ]

Yeah good point. I'm sure they wouldn't mess around if they thought there was risk of a lineman being in danger.

What I meant was that if the POCO is upset about an unauthorized connection they can cut you off.

[J.P.M.]

OK thanks!

I think the key here will just be to increase my methods of power generation. Adding wind and micro-hydro to my solar and generator should take some of the strain off the battery bank size.

But you have convinced me that grid tie is the way to go.

And before that, provided initial and ongoing expense reductions are two of the driving forces in this exercise, reducing the load is almost always more cost effective than meeting a larger one.

But, it's a free country. Pay your money, take your choice.