[RE-wrenches] Whole house solar backup using service entrance conductors from utility - transfer switch or stacked inverters to get 200amp through during normal grid ops?

[Jerry Shafer]

Connecting multiple Radians is an issue with the manual bypass at each
machine has one it is wise to replace them with a single 100 amp and in
your case maybe a 200 amp. There are some work-a-rounds but that has other
issues connected to it to. I have one of the first dual radian sun power
installs and there was quite a list of questions that came across when this
was done now some 3 years ago. We had the issue with Chillers needing to
operate and required the 100 amp pass through and operation in the off grid
mode.
Jerry

On Fri, May 15, 2015 at 7:43 AM, Howard "Scot" Arey <
scot.arey at solarcentex.com> wrote:

> Hi,
>
>
>
> Situation is owner wants grid-tied battery backup.  200amp switch on side
> of home with two main panels buried deep in this older home = limited
> ability to create a critical loads panel.  House has poor solar siting and
> really no space for battery room nor indoor space for Outback Radian setup.
>
>
>
> Opportunity is that the meter and utility pole is right next to boat house
> 100 yards away.  This boat house has great potential for solar and the
> space is perfect for batteries and inverters.
>
>
>
> My goal is to do “whole house backup” with customer doing manual load
> shedding as required.  I’d like to interconnect at the service entrance
> conductors after the utility meter (next to boat house).
>
>
>
> My dilemma is that the Radian has a 50-amp AC pass through rating so to
> prevent a bottleneck (code violation, too?) I think I need to stack 4
> Radians to get 200 amp pass through capability for when grid is operating
> normally.
>
>
>
> As you might see, this is quite expensive and I think over-kill for the
> owner’s backup power requirements.
>
>
>
> I know there are whole house auto transfer switches for generators.
>
>
>
> Question – is there some sort of whole house auto transfer switch where
> both the grid and the backup position are open (still allows PV grid-tied
> operations to sell back to grid and partially offset loads during normal
> grid ops) but closes the grid connection during grid failures so that the
> battery backup provides power (with 2 Radians only).
>
>
>
> *Howard “Scot” Arey*
>
> 254-300-1228
>
> scot.arey at solarcentex.com
>
>
>
> [image: logo from letterhead]
>
>
>
> _______________________________________________
> List sponsored by Redwood Alliance
>
> List Address: RE-wrenches at lists.re-wrenches.org
>
> Change listserver email address & settings:
> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
>
> List-Archive:
> http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html
>
> List rules & etiquette:
> www.re-wrenches.org/etiquette.htm
>
> Check out or update participant bios:
> www.members.re-wrenches.org
>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20150515/560debed/attachment-0002.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.jpg
Type: image/jpeg
Size: 31944 bytes
Desc: not available
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20150515/560debed/attachment-0005.jpg>