Demystifying Installation Variables and the Demystifying Installation Variables and the California Solar Initiative Inspection ProcessCalifornia Solar Initiative Inspection Process

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Today’s Objective

To prepare you on what to expect from a CSI Field Inspection and provide an overview of how and what measurements are taken by an inspector.

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CSI Measurements and Inputs

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EPBB Calculator

• Online tool that estimates the expected production of the systemand is used to determine the CSI incentive amount

• Takes into consideration equipment, location, orientation, tilt,shading effects and standoff height

• Measures the proposed system against an optimal system

• Derates the proposed system by a certain percentage (0-100%), referred to as the Design Factor, for any factors affecting the expected performance.

http://www.csi-epbb.com/

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Filling Out the EPBB Calculator

• Required Field Measurements & Tools Used

• Standoff Height (Tape Measure)

• Shading (SolMetric SunEye, Solar Pathfinder, other)

• Tilt (Digital Level)

• True Azimuth (Compass)

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EPBB Calculator

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Standoff Height

• Standoff Height - perpendicular distance from roof to the bottom of the module frame

• If not parallel to roof, use average height as shown below

Frame

6”

3”

(6”+3”)/2=4.5”

(SMAX)

(SMIN)

Mounting Method Choices:

0”

>0” to 1”

>1” to 3”

>3” to 6”

>6”

Please note: If the Mounting Method is not selected on the EPBB Calculator, it will automatically default to greater than 6” which can result

in an incorrect design factor

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Minimal Shading and Solar AccessObstructions such as trees, chimneys or nearby buildings can cast shadows on PV systems, which can reduce the system’s sun access thereby reducing the amount of electricity the system will generate.

You must indicate on the EPBB Calculator whether there is shading that will have an impact or not.

Option 1: Minimal Shading

• Minimal Shading-requires at least a 2:1 distance to height ratio of any object within the orientation of sun to the panels.

A

B

A > (2 X B)

For example, if line B is 13 feet, then line A has to be 26 feet or more

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If Not Minimal Shading…

Option 2: Not Minimal Shading, Enter Solar Access Values

• If a system does not satisfy the minimal shading requirement, a shading analysis needs to be performed to generate monthly solar access values.

• Solar access can be measured with tools such as the Solar Pathfinder or Solmetric SunEye (available at Pacific Energy Center to loan, visit www.pge.com/myhome/edusafety/workshopstraining/pec/toolbox/tll/)

• Measurements should be take at every major corner, but should not be more than 40 feet apart.

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Sample Reading

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Tilt

• Tilt - Angle at which the modules are mounted relative to 0º (flat horizontal surface)

• Modules that are installed on a flat roof will have a 0ºtilt

tilt angleº

Frame

Ex. 30º

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True AzimuthTrue Azimuth – the angle, usually measured in degrees(°), between a reference point

(True North Point 0°) and the direction of interest (direction panels are facing)

• The magnetic azimuth is measured using a compass, which does not represent the true north point because of the Earth’s magnetic fields

• Therefore, the magnetic azimuth must be corrected by adding (in Western U.S.) the magnetic declination of a specific location to give true azimuth

Magnetic DeclinationMagnetic North on a

Compass

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Magnetic Declination Correction• Look up magnetic declination for specific location at:

(http://www.ngdc.noaa.gov/geomagmodels/Declination.jsp)

• Enter in zip code, and it will calculate the magnetic declination for that location.

For example:

If you are in San Francisco and your compass shows you a reading of 180°,

you would look up the zip code (e.g. 94105) and add the given correction for magnetic declination of 14° to get a true

azimuth of 194°

On EPBB Calculator, enter the azimuth as 194°

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Tips for Determining Azimuth• Try to stay 10-15 ft away from metal, motors,

rooftop package units or magnets

• Store compasses away from cell phones and magnets

• Do not place compass directly on module or racking in case there are any magnetic fields present

• Check reading against tools like GoogleEarth. There is no azimuth function, but it can be used to provide sanity check for azimuth.

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Multiple EPBB Calculators

• Multiple EPBB Calculators are needed when there are multiple arrays that differ in one or more of the following:

• Stand-off Height

• Shading

• Tilt

• True Azimuth

• Panel manufacturer and/or model

• Inverter manufacturer and/or model

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28 panels:

Azimuth - South 180º

Tilt - 21º from horizontal Neighbor’s tree

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21

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Case Study 1

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21

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One array with the same:•modules and inverter(s)•stand-off height •shading•azimuth•tilt

Take 4 SunEye Snapshots, one at each corner of the

array

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Case Study 1: Calculate Solar Access Averages

Each snapshot will generate 12 monthly Solar access values

Jan 84%

Feb 89%

Mar 92%

Apr 93%

May 94%

June 95%

July 97%

Aug 96%

Sept 94%

Oct 92%

Nov 91%

Dec 89%

Array 1: Solar access values are averaged

for points 1-4

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Case Study 1: Calculate ImpactBecause entire array has the same stand-off height, shading,

azimuth, tilt and equipment, it is fine to complete only one

EPBB Calculator using averaged monthly solar access

values from the 4 points.

Array has 28 panels

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Case Study 2

9 panels:

Azimuth - East 90º

Tilt - 17º from horizontal

21 panels:

Azimuth - South 180º Tilt

- 21º from horizontal

Neighbor’s tree

1

23

4

7

56

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•Two arrays with the same module types and same inverter(s)

•Two arrays with different shading, azimuths and tilts•Take 8 SunEye Snapshots, one at each corner of each array

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Case Study 2: Calculate Solar Access Averages

Jan 89

Feb 90

Mar 92

Apr 93

May 94

June 95

July 97

Aug 96

Sept 94

Oct 92

Nov 91

Dec 89

Array 1: Solar access values

are averaged for points 1-4

Array 2: Solar access values

are averaged for points 5-8

Each snapshot will generate 12 monthly Solar access values

Jan 90

Feb 91

Mar 92

Apr 93

May 94

June 95

July 96

Aug 96

Sept 95

Oct 93

Nov 92

Dec 91

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Case Study 2: Calculate Impact

Array #1 has 9 panels

Because the two arrays have the different shading azimuths and tilts, two separate EPBB Calculator submittals are required - one for each array of unique orientation.

Array # 2 has 21 panels

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Field Verification• Field measurements should be verified pre and

post installation for accuracy• If changes have been made after installation is

complete, a new EPBB calculator must be submitted

• The following measurements must also be verified in the field post installation by the contractor*• Primary Method

• Solar Irradiance (Irradiance Meter)• Temperature (Thermometer)• Inverter Output

• Compare to Field Verification Output Table (next page)*Method used by our inspectors

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Field Verification Output TableEx. Irradiance = 718 Ambient Temperature = 72

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CSI Field Inspections

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CSI Field Verification Inspections

Purpose• To verify that the project is installed as represented in

the Incentive Claim Form/Final EPBB Calculator, is operational, is interconnected and meets the eligibility criteria of the CSI Program.

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Selection of CSI Projects for Site Inspections

First two Incentive Claim Forms submitted by a contractor will beinspected

Projects <50 kW:

• After two successful inspections, projects will be randomly chosen for inspection

• Random means approximately 1 in 7 applications per applicant

Projects >50 kW:

• Program administrator’s discretion

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CSI Inspection Verification

Inspectors will verify the following:

Module & Inverter Equipment

- Manufacturer

- Model Number

- Quantity

*If module nameplate is not visible, invoice is necessary to verify manufacturer and model

Installation Parameters Verified

Measure:

- Tilt

- Azimuth

- Standoff Height

- Shading of array(s)

-Solar Irradiance

-Ambient Temperature

Operation

- System is Interconnected, operational, and output is reasonable for conditions at time of inspection

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Coordination of InspectionsApplicants are not required to attend inspections, though they are highly encouraged to do so, especially…

• For first time Applicants

• For projects with significant shading

Inspector will require physical access to the equipment

• Inspector will contact Applicant for notification of inspection

• Inspectors prefer that the Applicant coordinates with the Host Customer to allow access

• If Applicant prefers, the Inspector will coordinate with the Host Customer.

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Access Issues to Modules

If issues exist that prohibit access, such as

• Weather conditions that may render it unsafe to mount roof

• Roof that are too steep or have other structural issues, etc.

We will require assistance from Applicant by

• Providing Inspector shading analysis for EPBB Calculator

• Providing Inspector invoice indicating the module manufacturer, model and quantity

Inspector will still verify if the system output from the inverter is reasonable given the conditions during the inspection

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Inspection Results• Inspector will verify measurements are within the following tolerances:

• Tilt +/- 3º

• Azimuth +/- 5º

• Shading +/- 5%

• If inspection results fall within tolerances• Inspector will accept EPBB calculator as submitted with the Incentive Claim

Form and send report to PG&E• PG&E will pay incentive as requested in the Incentive Claim Form

• If inspection results fall outside of tolerances• Inspector will communicate discrepancies to Applicant onsite, if present

during inspection• Inspector will run a new EPBB calculator to get a revised CSI rating and

incentive amount• Inspector will send it along with the report to PG&E for further evaluation

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Inspection Results Cont’d

• PG&E will compare recalculated incentive to submitted incentive amount in Incentive Claim/EPBB Calc.

•If incentive amount discrepancy is within 5%

•PG&E will pay revised incentive amount based on new EPBB Calculator from inspection

•If incentive amount discrepancy is 5 -10%

•An Infraction will be issued

•If incentive amount discrepancy greater than 10%

•A Failure will be issued

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Infractions and Failures

• If an Infraction or Failure is issued, the following two options will be communicated to the Applicant and Host Customer and a decision must be made within 30 days:

1. Applicant can accept new recalculated incentive amount

2. Applicant can dispute the accuracy of results/measurements

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Infractions/Failures Cont’d

• 3 Issued Infractions = Failure• Low volume Installer (< 200 systems per year Statewide)

• 1 failure = warning• 2 failures = up to 100% inspection for Applicant’s projects• 3 failures = Disqualification for up to 1 year from CSI Program

• High volume Installer (> 200 systems per year Statewide)• 4 failures = up to 100% inspection for Applicant’s projects• 5 failures = Disqualification for up to 1 year

• All infractions/failures removed after good standing for 1 year of last failure

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How to Prevent Failed Inspections• Make sure Incentive Claim Form and EPBB Calculator

accurately reflect “as-built” system

• If any changes occur, send updated EPBB Calculator to

Program Administrator before the inspection occurs

• Revised EPBB Calculators will not be accepted by Inspectors

on-site

• Attend the inspection to familiarize yourself with the inspection

process and program requirements

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Questions?

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Future Webinars/Classes

• Tue, Oct 13, 5-6pm-PG&E and Solar-Internet

• Wed, Oct 14, 6-8pm-Solar Power Basics for Residential Customers-SF PEC

• Wed, Oct 14, 9am-12pm-Integrating Energy Efficiency and Renewables in Commercial Retrofits-SF-PEC

• Fri, Oct 16, 9am-4:30pm-Basics of Photovoltaic (PV) Systems for Grid-Tied Applications-Stockton—ETC

•Tue, Oct 20, 12-1pm-Financial Analysis-Internet

• Tue, Oct 20, 6pm-8pm-Solar Water Heating Basics-SF PEC