[RE-wrenches] large array on 200 amp service

Jason Szumlanski jason at floridasolardesigngroup.com
Fri Sep 25 07:14:22 PDT 2015


Supply side interconnection is the only option, usually tapping service
conductors in main panel between meter and existing main. Without other
complexities present, it's pretty straightforward. We're running into a lot
of meter/main combos that don't have conductors that can be tapped (copper
bus bars between meter socket and main breaker. That has required changes
of service equipment, which can be pricey.

One thing that you should consider... Just because the service is 200A, it
doesn't mean the utility transformer can handle the backfeed from a very
large PV array, especially if a neighbor on the same transformer has a PV
system. In one extreme case we had a single 25kW pole-mounted utility
transformer feeding SIX tenant meters at a single property ranging from
100A to 200A! We wanted to install a PV system larger than 25kW (about 105A
rating), and the utility blocked the project, denying the request to
upgrade the transformer, even at the customer's expense. It was a bit more
complicated than that, but bottom line it was a pure political/principle
stance. If we had the legal department the utility does, we probably would
have fought it.

It's a lesson to check the utility transformer serving the property, not
just the service rating.



On Fri, Sep 25, 2015 at 9:10 AM, gary easton <gary at arp-solar.com> wrote:

> Hello Wrenches,
> What are folks doing when installing 100A plus of solar into a 200A
> service?
>
> --
> Gary Easton
> Appalachian Renewable Power
> Stewart, Ohio 45778
> NABCEP Certified Solar PV
>
> T: 740-277-8498
>  www.arp-solar.com
>
> “First they ignore you. Then they laugh at you. Then they fight you. Then
> you win.”
> ~Ghandi
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20150925/1c8a7d75/attachment-0002.html>


More information about the RE-wrenches mailing list