Grid Tie Solar Layout Help

funidea

I am doing a self install and need assistance on the 5 lower items in the picture?
Where do i put them? Inside or outside? at the Shed or at the House? AC or DC?
Thanks

dsp3930

Re: Grid Tie Solar Layout Help

My take ....

Put the Inverter AC Disconnect outside next to meter as it is required to be there so the power company can cut your inverter power to the grid if needed. (external lockable disconnect)

If you put your inverter in the house, then everything goes in the house and the wiring to your shed is DC.

If you put your inverter in the the shed (and all componets can be kept dry and within design hot/cold tolerances, then everything goes in the shed and the wiring to your shed is AC. Add in the shed an additional AC Disconnect if your inverter doesn't have one built in.

A few parting thoughts that may help you make up your mind... :-)
If it is freakin' cold in the winter and you need to do some emergency work, will you want to do it in the shed?
If it is blazin' hot in the summer and you need to do emergency work, will you want to do it in the shed?
If it is pouring rain or bad weather and you need to do emergency work, will you want to do it in the shed?

niel

Re: Grid Tie Solar Layout Help

dsp is being a bit mellowdramatic about it, but i agree with him. also the dc voltage will be higher than the ac voltage so this will help overcome resistive losses in transitioning from the shed to the house. what you may want to do is allow for more wiring in the underground conduit by using an extra large conduit and even leave a rope to tie off to new wires to pull them through as any future expansions would need. aka thinking ahead.

dsp3930

Re: Grid Tie Solar Layout Help

Yes, I was just a bit. :-)

In all seriousness, I personally think inside your house is the best way to go if possible -- unless you have another reason that makes you think it should be in the shed.

A few do come to mind:

You used the shed as a selling point to your significant other. IE. "It will all go outside"

You are want to put all your solar handywork in one location and want to be able to display it easily.

You don't have a location inside where you want to (or can) put all the equipment.

Where you would have to locate your inside system would not be aesthetically pleasing in your mind.

David

cdherman

Re: Grid Tie Solar Layout Help

Also to consider:

Do want AC power in the shed anyhow? I assume yes. There are rules about running AC and DC lines in the same conduit (don't ask me, I only know they exist). I *think* its basically a no no.

And if you want more than a very small number of circuits, those same rules will require you to put a sub panel in the shed anyhow.

So if you are stuck putting a dedicated conduit for AC to your shed, as well as a sub panel, then you might be better off putting the whole works in shed.

Bear in mind, the utility will still want a lockable AC disconnect close to the meter. Unless your shed will also have circuits that feed other, critical loads, you CAN just have the lockable disconnect disconnect all the AC to the shed. This would knock out all the power to the shed and the PV as well. But since this is unlikely to occur frequently, if ever, only a very critical load would be a reason to avoid this approach.

This is the way I did it on my property -- in my case the sub panel was already in the shed, so it was a no brainer.

A critical load that would preclude that would something like a heat source for delicate plants, animals etc. Or something that would overheat or freeze in only a few hours. Refrigerators and freezers don't really count, as the lockable disconnect will only be thrown when the utility is doing work in your local viscinity and only for a few hours at a time, in all likelyhood.

Edit:

It also occurs to me that we don't know where you are in the world. If you are fairly southerly and the grid tie system is being used primarily for cooling or your home usually requires cooling and seldom requires heat, then you should really consider locating the inverter in the shed. All the waste heat from the inverter will need to be pumped back out of the house.

If however, you are northerly and the heat from the inverter would come in handy most months of the year, then by all means, put it in the house.

Inverters chunk out a good bit of heat. In southerly climes, put them at least in uncooled spaces like the garage. Putting it in the basement, if its unfinished might seem attractive, but that heat will rise and the whole house will need more watts to cool.