[RE-wrenches] UL and Grid-tied Battery Back Up Systems

[Matt Lafferty]

Hi Joel,

I've seen a handful of Sunny Islands go in after the initial PV system is
installed. Six or seven. And I've seen Sunny Islands go in where there isn't
any PV. All but one of the ones that I've seen installed after the PV have
been permitted and inspected. ALL of these systems went in because of
utility reliability problems. (Pay attention Mr. AGM... When people do this,
they are paying a lot of money BECAUSE YOU CAN'T DO YOUR JOB.)

With regard to any realistic hazards to utility personnel or operations
these systems may cause... There aren't any. There weren't any in 2002 when
the SW scare caused the turds in LADWP's bowels to harden up the first time.
Every modern battery-based inverter that I know of has a LISTED transfer
switch to isolate itself from the grid on loss of grid power. This is as
much to protect the inverter from the broken grid, as it is to protect the
broken grid from the inverter.

The crux of the matter, with regard to AC coupled inverters, is that these
systems don't have a thing to do with the PV, per se. They can be, and are
being, installed in applications with or without PV on a regular basis. Just
like any electrical work, they are required to be permitted and inspected
when installed. If a property owner chooses to not get the required permits,
it's on them. Stuff happens. People do sh*t. Every day. Mr. AGM is chasing a
boogeyman.

I believe that A LOT MORE PV WILL BE INSTALLED WITHOUT PERMITS AND UTILITY
INSPECTIONS when we finally do away with the incentive programs. That's when
the guy should be worried. After the incentives stop. Tell him that the best
way to ensure that PV systems are inspected, is to have a robust incentive
program and keep everybody "in the system" so to speak. If he's so gosh-darn
worried about people adding AC coupled backup systems after the initial PV
system is inspected, tell him to start an incentive program for those, too.
No permit and inspection? No money. Simple as that. Pick a dollar figure
that is twice as much as the permit fee and everybody will go for it.
Seriously.

The folks who are gonna do guerilla stuff are gonna do guerilla stuff. Same
as it ever was... In the case of a "customer adds battery backup without a
permit and it might hurt the utility or lineworkers"... That's stupid.
Number one, the number of potential customers who might do this is
infinitessimally small. I would be totally shocked if there were 100 in
LADWP territory in a year. My best guess is more like half a dozen.
Remember, this is ONLY the guerilla stuff.

But let's use 100 as a worst-case number. 

"OMG! A hundred?" (Gasp, flutter, faint)

Of that 100, 100 of them are now paying a higher electricity bill than they
would otherwise be. Score one for the utility. As long as they keep the
power on. 

Let's say that 80 of them use modern, off-the-shelf equipment. Doesn't have
to be wired right. Doesn't have to be inspected. Just modern, off-the-shelf
and IEEE 929 compliant. If it's like that, ain't no harm coming to the grid
in no way. So, now we're talking about 20 needles in the smoggy haystack of
LA. 

How big are they? What kind of fault currents can they put out? What kind of
backyard inventions are they? What if they are backfeeding the grid when
it's operating and running their meters backward? What if they are capable
of backfeeding the grid during a power outage? Where are they? How dangerous
are they to the grid and grid workers? 

That's the scary part, nobody knows... Ooooh.... Ooooohhh.... Boogeyman!

Let's say 10 of the 20 are rogue, independent, half-witted inventors
scattered all over; and the other 10 are a bunch of Tea Party Freaks on one
cul de sac who bought some cross-wired crap from a screaming freak they
heard about on Fux Noise... Really dangerous stuff here... 

The inventors ain't gonna hurt you. These types aren't gonna have unlimited
batteries and aren't gonna be building any really big power stuff. They are
tinkerers. Low-power. Proof of concept. What do you even care if they are
charging their batteries off the grid and discharging them back onto the
grid? Unless they are over 10kW, it's no more disruptive to your grid
operations than a hot tub. The best they can do is have a net increase of
2.5% in their electricity usage. During a power outage, the loads between
their place and the open grid is gonna suck their batteries inside out if
their stuff stays connected. If they weren't sophisticated enough to build
something that isolates on power loss, their equipment will either cook or
go dead in no time.

The Tea Party cul de sac worries me. Here you have 10 houses with armed
freaks inside. And now you're telling me they have batteries, too? YIKES!
Nah. Not gonna happen. This is a flawed scenario. Tea Party Freaks buy
GENERATORS!

So, to recap, there were only 90 guerilla battery systems that year after
all. 80 of them were safe due to the equipment. 10 of them were safe due to
the ignorance of the owner. And the real danger to the grid is a cul de sac
of Tea Party Freaks with generators and double-male extension cords.

In reality, you're probably talking about a half dozen unpermitted battery
backup systems installed down there a year. I would be really surprised if
more than one was in some way capable of backfeeding to a faulted grid for
longer than a couple seconds. Any system that is bad for grid operations
will show itself sooner, rather than later, in one way or another. When
these things are found, they need to be dealt with appropriately. 

I served as the Grid Cop in Sacramento for a couple years. In the course of
my travels, I got to see some colorful people and some colorful
battery-based setups. I got to help Y2Kers get onto Net Metering. I had to
tell people that their power was gonna be shut off if they didn't physically
take stuff out. I had to do re-inspections. I probably saved a couple homes
from burning down. And maybe a life or two. I saw homemade equipment and
factory made stuff. I saw double-male extension cords. I saw a pile of
burned up small square-wave inverters that one guy smoked trying to hook
into the house wiring. That guy had a couple modules lying on his roof with
an orange extension cord coming thru the window to the charge controller...
The long and the short of it is that none of these people stood a chance of
hurting the grid with their equipment. And they weren't trying to.

With all due respect to the AGM... He's whacked if he's trying to use this
boogeyman as an obstruction to PV. Tell him to go home and count up all the
unpermitted things around his own house. Tell him not to forget to count the
ceiling fan he had put in the bedroom and the water heater he had replaced.

If he wants to do something to keep the grid safe, start registering gas
cans.

$0.02001

Matt Lafferty

-----Original Message-----
From: re-wrenches-bounces at lists.re-wrenches.org
[mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of Joel
Davidson
Sent: Tuesday, October 05, 2010 1:53 PM
To: RE-wrenches
Subject: Re: [RE-wrenches] UL and Grid-tied Battery Back Up Systems

Hello Peter, It was good to see you at the LADWP Commissioners Meeting even
though we didn't have time to talk. I told Mr. Benyamin, LADWP AGM, at the
meeting that there were no safety issues regarding grid-tie PV system with
batteries because the inverters were IEEE 929 compliant. He said he was
concerned about batteries being added to a PV system after the initial
utility inspection. I told him that batteries can not be added to a
non-battery inverter. He said it is being done so the conversation ended. 
How many people are adding battery inverters later? I've done hundreds of
grid-tied systems and never added a battery inverter and battery bank after
the initial installation.

Wrenches, are you adding batteries to non-battery grid-tied PV systems after
the initial installation? If yes, what inverter and how do you deal with the
inspector?

Joel Davidson

----- Original Message -----
From: "Joel Davidson" <joel.davidson at sbcglobal.net>
To: "RE-wrenches" <re-wrenches at lists.re-wrenches.org>
Sent: Tuesday, October 05, 2010 7:43 AM
Subject: Re: [RE-wrenches] UL and Grid-tied Battery Back Up Systems


> Peter,
>
> California utilities use to require operating steps (list not UL listing) 
> for all grid-tied systems in the interconnection application. A copy of 
> the operating steps from the equipment manual sufficed.
>
> Joel Davidson
>
> ----- Original Message ----- 
> From: "Peter Parrish" <peter.parrish at calsolareng.com>
> To: "'RE-wrenches'" <re-wrenches at lists.re-wrenches.org>
> Sent: Tuesday, October 05, 2010 4:05 AM
> Subject: [RE-wrenches] UL and Grid-tied Battery Back Up Systems
>
>
> Are there UL testing procedures for Grid-tied Battery Backup Systems, such
> as the Xantrex XW systems and the Outback GVFX systems? The reason for my
> inquiry is that the Los Angeles Department of Water and Power intends to
> require that "...applicants installing Battery Backups on their solar
> systems to submit an Operational Listing detailing a precise list of steps
> of what were to happen if the LADWP grid were to lose power."
>
> - Peter
>
>
> Peter T. Parrish, Ph.D., President
> California Solar Engineering, Inc.
> 820 Cynthia Ave., Los Angeles, CA 90065
> CA Lic. 854779, NABCEP Cert. 031806-26
> peter.parrish at calsolareng.com
> Ph 323-258-8883, Mobile 323-839-6108, Fax 323-258-8885
>
>
>
>