[RE-wrenches] What is a solar installer...?

[Peter Parrish]

Hello Benn,

I have some pretty strong opinions about this subject but some of them are
reflections on politics as opposed to sound engineering design and best
installation practices.

See my comments interspersed below:

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

 
________________________________________
From: re-wrenches-bounces at lists.re-wrenches.org
[mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of benn kilburn
Sent: Thursday, October 14, 2010 1:12 PM
To: Wrenches
Subject: [RE-wrenches] What is a solar installer...?

Wrenches,
a colleague of mine is looking for feedback to the following email he
received regarding PV installers and electrical work.  I have responded to
him, however, I am quite interested to hear this list's response....


LETTER--
'Colleague'  - next week Alberta’s “major municipalities” electrical chief
inspectors are getting together to talk about issues. One item I have asked
to put on the agenda is qualifications of solar installers. I hope to see a
start on forming some type of agreement on is who is qualified to do what
work on a solar installation and what is considered electrical work that
only electricians can perform. 

>>> In California, we have two specialty contractor licenses Solar (C-46)
and Electrical (C-10) and well as the General license (B) -- which are
qualified to install PV systems. I myself am a C-46 but I will probably step
up to taking the C-10 for political reasons.

There seems to be courses popping up all over to teach everyman to be a
solar installer, but what work is clearly reserved for electricians to do?
The Safety Codes Act speaks to Electrical Systems, CE (Canadian Electrical)
Code defines electrical installation and electrical equipment.

>>> Most (but not all) of the authorities having jurisdiction over PV
installations (here in California these are City or County Building and
Safety Departments) see PV as just an electrical system and check plans and
do inspections accordingly. However, the design and installation of the
racking system is an essential part of the overall picture. PV systems need
to be attached to properly transfer the dead and live loads from the PV
array to the major structural elements of the roof (e.g. rafters) and done
in such a way to preserve impermeability of water (and snow). In many parts
of CA we get 90 mph winds, which can transfer substantial loads to the
racking system. Finally, Fire Departments have begun to analyze PV array
layouts from the perspective of access to, and movement on, a roof during a
fire. Most of the racking systems are pre-engineered, and if you follow the
design guidelines, you should be okay. What I am trying to say is that
proper mechanical/structural design is important (maybe a 1/3 of the design
and 1/2 the installation) but the manufacturers to a good job of providing
guidelines for the installers.

>>> Electrical design is more involved and there are more opportunities to
commit design errors: PV string sizing, voltage drop and ampacity
calculations, over current protection, component selection, and grounding.
But here's the catch: almost all of this material is PV-specific, and very
few electricians have been educated or trained in this area. They pick it up
as they go along (poor choice) or take a course specifically in the area of
PV design and installation (better choice).

>>>Let me make a WAG. If one were to randomly pick a C-10 electrician out of
the statewide pool and do the same for a C-46; the C-46 would be better
prepared to design and install a PV system than the C-10. The overwhelming
majority of residential installs in CA are done by solar contractors, I am
less sure about small commercial (say up to 15 kW to 50 kW).
 
 What I hope we accomplish is a stance we can take to the EIAA (Electrical
Inspectors Association of Alberta) conference then to Apprenticeship and
Industry Training who ultimately enforces who does work in the trade.

>>> IMHO, the first thing you should look at is a Solar Contract license --
if you don’t already have one. The second thing is to make available PV
classes for electrical (or other) contractors. There are scores of
consultants/instructors in the US that are prepared to provide this service
on an ad hoc basis. However, an on-going program at a local college offering
courses on PV as well as other renewable energy disciplines (e.g. wind)
would be the best long term solution.
 
To me the PV module racking can be done by anyone, but almost all of the
rest of the installation – from wire pulling to interconnecting modules,
mounting of the inverters etc falls clearly into the scope of practice for
electricians.

>>> You are wrong about that. And the way I know you are wrong is this. We
get about one call a month from a PV system owner who wants us to take a
look at their system and fix it. About 1/2 of these calls involve bad
inverters (a relatively straightforward test and swap out procedure) but
almost all of the other half involves bad rooftop installations: poor DC
wiring management, poor grounding of PV modules and racking, poor flashing,
poor mechanical design and attachment. Leaky roofs represent maybe a 1/4 of
the total service calls. We rarely find bad wiring down on the ground.

>>> In my "Hall of Shame" there is a system that were asked to look at by a
large PV integration company that had sub contracted out work to a local
electrician. Here is what we found:

(1) The attachment to the roof was done with L-brackets without flashing or
caulking (roof was perhaps 3:12).

(2) The racking system was comprised entirely of strut and galvanized
fasteners.

(3) The module "clamps" were comprised of galvanized machine bolts with
fender washers. The bolts were torqued sufficiently to deform the fender
washers. I wondered to the extent that the "point stresses" were transferred
to the PV modules and how long the PV modules would last.

(4) The DC wiring lay on the roof in many places. Modules were grounded but
the strut wasn't.

(5) The conduit, wiring, component selection and grounding on the ground
were fine.

So you can see that ALL of the problems with this particular install had to
do with the PV-specific nature of the design and installation, and none had
to do with general electrical work.

One of the bigger players in the industry is saying “its now getting to be
all plug and play” and anyone can be an installer.

>>> Big players in what industry? There is a trend to more integrated
design, but "plug-and-play"? Not yet. 
 
 Hoping an agreement like this can make it a level playing field and
consistent across the Province.
 
 What are your thoughts?

>>> you've got them.

 
BACK TO ME
my thoughts are similar to the ones above, that the racking alone can be
installed by any 'properly trained' person.  However pretty much every other
aspect of a PV install directly falls under the scope of an electrician and
needs to be preformed by a journeyman or apprentice under the supervision of
a journeyman electrician.

>>> And how do you propose to insure that Joe Blow is "properly trained"?

>>> How do you insure an electrician has the PV-specific knowledge and
training?


the following paragraph is from recent past EIAA technical conference
minutes.
 "Alberta Municipal Affairs (AMA) was asked (earlier in 2009 by a
Municipality) for an opinion on the Permit Regulation regarding Homeowner
Permits. The Permit Regulation states a homeowner may be issued a permit
where the electrical system serves that dwelling. A photovoltaic system that
is tied to the grid (utility interactive) serves other than that dwelling.
The response back from AMA confirmed utility interactive PV systems do serve
other than the dwelling and as such permit issuers should not be issuing
homeowner permits for utility interactive PV systems."

>>> I am not sure if the question is about the requirement for a Contractor
vs Homeowner to pull the permit., or not. I don’t think owner/builders
should be allowed to install PV.

My thinking is that this would include the addition of 'plug and play'
modules/inverters to an existing system as well  ...any comments on this
one?

>>> I wouldn't get too involved with the ramifications of "plug-and-play"
until it becomes a reality.

cheers,
benn

DayStar Renewable Energy Inc. 
benn at daystarsolar.ca
780-906-7807 
HAVE A SUNNY DAY