Shade Measurements Webinar

Shade Measurement Topics • Site analysis considerations – Why measure shade? – Terminology – Shade measurement strategies

• Using the SunEye – Live demo – Common problems and solutions – State rebate requirements

• Resources, Questions and Answers

Solmetric Corporation • • • •

Founded in 2005 25 employees Headquarters in Sebastopol, CA Mission: to improve the effectiveness of solar systems and those who install them by providing high quality, easy-to-use, accurate tools with embedded technical know-how.

Solmetric Solutions

Why measure shade?

• • • •

Choose optimum location for panels Identify issues early in the process Predict energy production accurately Ensure optimum financials – State rebate – Feed in tariff – Renewable Energy Credits

Note: Shading can have disproportionate impact on energy production

Sun Trajectories (“Sunpaths”)

Noon

Sunrise

Sunset

Annual sun path example

Hemisphere view (Skyline)

Important Terms • • • • • •

Irradiance Insolation Solar Access TOF (Tilt Orientation Factor) TSRF (Total Solar Resource Fraction) Obstruction Elevation

Irradiance Incident solar radiation (power) per unit area in kW/m2

Approximately 1 kW/m2 at the earth’s surface.

Insolation – Solar Energy over Time per unit Area in kWh/m2

1 kW/m2 of irradiance for 6 hours = 1 kW/m2 x 6 hr = 6 kWh/m2 of insolation. 6 kWh/m2 of insolation on a 2 sq-m surface = 6 kWh/m2 * 2 m2 = 12 kWh of energy received by the surface.

San Diego insolation

Roof Azimuth Tool

Solar Resource Terms • Insolation. Incident Solar Radiation, kWh/m2 • Solar Access. Insolation compared to no shading, in field of view of the panel. • Tilt and Orientation Factor (TOF). TOF is the solar insolation at the actual tilt and orientation divided by the insolation at the optimum tilt and orientation, expressed in percent. • Total Solar Resource Fraction (TSRF). TSRF is the ratio of insolation available accounting for both shading and TOF, compared to the total insolation available at a given location at the optimum tilt and orientation and with no shading. TSRF is also expressed in percent, according to the following equation: TSRF = Solar Access * TOF.

Solar Resource Terms Optimum Annual Insolation

TOF Solar Access Loss due to shading

TSRF

Loss due to suboptimal tilt/azimuth

Solar Resource Example Optimum Annual Insolation

TOF Solar Access Loss due to shading

Good Solar Access means little shade, but not necessarily the best solar production.

TSRF

Loss due to suboptimal tilt/azimuth

Solar access and TOF/TSRF examples

Obstruction Geometry

H/D = TAN (θr)

θr = TAN-1( (H/D)

• D/H as high as possible • D/H > 2 is California Minimal Shading ~26 degrees • D/H > 3+ is “shade free 9-3”

Obstruction Elevation example

Steps for measuring solar access Electronic Bubble Level

1. Point south* 2. Hold Level 3. Press the button

* Point south in the northern hemisphere; point north in the southern hemisphere.

Electronic Compass

Shade measurement strategies • Take multiple point readings – Maximum 5 meters between readings

• Measure at height of modules

• Look for worst case – Array corners – Points closest to obstructions

• Take Average or worst case readings – Solar access – Obstruction elevation angles

• Map-out shade free zones

Note: Be sure you meet the requirements of your state program and rebate calculators

Solmetric SunEye Models 100 Series • Introduced in 2006 • Thousands in use by installers worldwide

Model 210 • Introduced in Feb 2010 • Popular features very well accepted

Introducing the Solmetric SunEyeTM 210 • What’s New? – – – – – – – – –

Easy one-handed operation Brighter, higher Res. Display (4x) Electronic compass & inclinometer Dynamic Site-survey mode Large capacity battery Integrated stylus holder Integrated GPS option Impact resistant molded case 2 year warranty

Comparing to the original SunEye • What’s the same? – – – –

Easy to use and navigate user interface Powerful shade analysis software On-board editing tools for “What-if” Results viewable right on the SunEye • Solar Acess, Solar Resource • Sunpaths, Monthly Solar Access • Obstruction Elevation Angles – Desktop Companion Software included

Power

Navigation, Select

Orientation (Compass, Inclinometer, GPS)

Home Session Properties

Preview/QuickLaunch (like Menu/Skyline/New)

Built-in Inclinometer • • •

Measure Tilt and Azimuth Set SunEye on plane of solar array to measure tilt Point arrow toward array heading to read azimuth

Site-Survey Mode • • •

Survey site Sunpaths adapt as you move device See how obstructions and sunpaths overlap

To view shading in a month/time window only:

“Windowed Access” Preview mode

To mark “shade free zone” move away from obstruction until it is outside the window and mark roof with chalk.

Annual Sunpaths View

Sky type • Reduces skyline detection errors • Adjusts color balance • Three settings – Clouds and Blue Sky: Good for very bright days with hazy sky conditions – Normal: default and generally ok for most situations – Shaded: Optimum for detecting tree edges

Sky type examples Normal

Normal

Clouds and Blue Sky

Shaded

Alignment issues • If not aligned properly, warning message appears • Retry to repeat measurement • Continue accepts it as 180/level

If metal on roof affects the compass: “Align to Target” • • • •

Set target to arbitrary known value Compass is ignored during measurement Measurement is referenced to user-entered “target” Top of screen is target heading, included in report

“Align to Target” • Skyline may look distorted in report due to autoscale function and rotation • Heading is shown on report and in Skyline Properties”

SunEye Extension Kit • SunEye Extension Kit – Make measurements from the ground up to 18 feet – Mounting plate secures SunEye without obstructing camera – Rotation of pole arms and then snaps picture – Automatic azimuth and level corrections

SunEye GPS Add-On • GPS option integrated into 210 • Detects latitude/longitude for session location and automatic sunpath generation • Records location of each skyline data set collected • Reports include file for Google Earth™

SunEye GPS output to Google Earth™

Data transfer to computer via USB • SunEye stores more than 100 Skylines in memory • Transfer data to PC for further analysis • View and edit data in same way as on hand-held • Create reports and export files to design tools

Solar Access and Shade Report Client Information

• All session data is combined into a single hypertext document • Converts to MS-Word™ • View, Email, or print

Installer business information/logo

Access raw data files

Day

• Import data files into design software – Excel spread sheet, OnGrid, PVOptimize, PV*SOL, T*SOL, PVSyst, QuickQuotes, CPF Tools

1 2 3 4 5 6 7 8

Month Jan Feb Mar 54.17 54.99 67.64 54.17 54.99 67.64 54.17 54.99 67.64 54.17 54.99 67.64 56.63 54.66 67.77 56.63 54.66 67.77 56.63 54.66 67.77 56.63 54.66 67.77

Updated Software and Accessories • New software updates available from: www.solmetric.com – Includes handheld and PC updates – Set for auto-update

Resources • User’s Guide accessible via desktop software – Help>Solmetric SunEye User’s Guide…

• Knowledge base at: – http://www.solmetric.com/knowledgebase.html

• Technical Support – 1-877-263-5026, opt 2 – [email protected]

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Dec-Jan issue: “Solar Site Evaluation” www.solarprofessional.com

SunEye’s Key Benefits • Accuracy and repeatability – Calibrated fisheye lens – Multiple users, different situations, same results

• Speed and convenience – Full Sky Preview mode – One shot for the entire skyline – Point and shoot capability

• Data transfer – Solmetric PV Designer – Other Programs

PV String Simulation Model Sun position, panel tilt/Azimuth Irradiance, shade, temperature, wind speed

Module bypass diode configuration Module parameters Inverter parameters String wiring AC KWh

Solmetric PV Designer

SunEye Desktop and PV Designer SunEye Desktop Software Included with SunEye www.solmetric.com/support.html Transfer data from SunEye device SunEye device features, views, editing, etc. Solar Access, Solar Resource, Windowed Access, Obstruction Elevation, etc. Maintain session data on computer Export reports and access shade images and shade data files Print shade reports and use images for proposals

PV Designer Software $400 per year per user www.solmetric.com/support.html PV layout and estimation of kWh Advanced hourly weather data, including TMY4 Database of modules, including dimensions Database of inverters, including limits String definition and sizing Limit checking for voltage, current, power Compare up to four designs Import SunEye Skylines as icons onto roof surface Shade adjusted energy calculations Data display of monthly and annual totals Summary pdf report and hourly csv output files

Questions?

Solmetric Corporation www.solmetric.com 1-877-263-5026