PV System Site Assessment#SolarMOOCSolPowerPeople, Inc.May 30, 2013w/ Sarah RaymerAKA Ms. MOOCNABCEP Certified PV installation ProfessionalCertificate #: 042013-107
Solar Resource:● What is the solar energy productionpotential for the location?● How does the specific site effect theinstallation - production and installationwise?● Customer assessment: What does thecustomer expect and want?Solar Site Assessmentobjectives:
● Solar Resource:○ Latitude○ solar sun path charts○ Altitude and Azimuth - sun and array positioning● Site Specific Practical:○ Shading - Solar Pathfinder or Suneye○ Mounting methods and locations○ Component locations and wire runs○ Electrical service - new construction or retrofit○ Roof or soil conditionsSolar Resource and SiteAnalysis
Solar resourceDoes the sun shine?● What does data say for location?○ Latitude, solar sun path charts■ Azimuth - position relative to South■ Altitude - how high in the sky● What is the weather/air like?○ wind patterns○ rainfall○ pollution
Latitude has anincredible influence onthe available solarresource.
Austin, Texas:84 days rainfall average229 sunny days/year30º Latitude489 ft. AltitudeFrankfurt, Germany:111 days rainfall average1,586 hours sun/year51ºN Latitude364 Ft. AltitudeLatitudeGermany:2011: 69,6842012: 102,024USA:2011: 4,3832012: 7,665MWp Peak Power Capacity (installed, not resource)
Kenya:13 - 71 days rainfall3,579 Hours/year0º Latitude6000 Ft. AltitudeSydney:155 days rainfall235 sunny days/year39ºS Latitude128 Ft. AltitudeKenya:Australia:2011: 1,2982012: 2,291South Africa:2011: 412012: NAMWp Peak Power Capacity (installed, not resource)Latitude
Location and LatitudeSun strike, wind/weather patterns, elevation
Berlin, Germany:111 days rainfall average1,586 hours sun/year51ºN Latitude114 Ft. AltitudeGermany:2011: 69,6842012: 102,024
Austin, Texas:84 days rainfall average229 Sunny Days/year30º Latitude489 ft. AltitudeUSA:2011: 4,3832012: 7,665
Kenya:13 - 71 days rainfall3,579 Hours/year (325 days)0º Latitude6000 Ft. AltitudeSouth Africa: 2011: 412012: NA
Sydney:155 days rainfall235 sunny days/year39ºS Latitude128 Ft. AltitudeAustralia:2011: 1,2982012: 2,291
Solar and Wind Energy Resource Assessment:http://maps.nrel.gov/sweraOther examples:Indonesia is practically at the equator, yet thesolar resource is fairly poor because it rainsthere SOO much.
Other examples:Hawaii- 10 climate zones in 4000 square miles
Azimuth and altitude of thesun and array dramaticallyaffect the ability to maximizea locations natural solarresource.graphic from: astronomy21st.blogspot.com** Note: mostlyusing Northernhemisphere forexamples.
http://www.solarfeeds.com/The solar window is defined by the solar altitude and solarazimuth.
A sun path chart is a graphic representation of the solarwindow that gives precise data regarding the exactlocation of the sun at all times of the year.
S0ºE90ºW-90ºN-/+ 180ºWhat is the azimuth angle of each array?Which one will produce the most in the morning?Which one will produce the most in the evening???Array azimuth
S0ºE90ºW-90ºN-/+ 180ºWhat is the azimuth angle of each array?(At what angle does it face in reference toSouth?)40ºWor -4050ºE
S0ºEWN-/+ 180ºWhich one will produce the most in the morning?Which one will produce the most in the evening?40ºWor -4050ºE
S0ºEWN-/+ 180ºWhich one will produce the most in the morning?Which one will produce the most in the evening?40ºWor -4050ºEWill do best in the AM, when Sun is in the Eastern skyWill do best in the PM, when Sun is in the Western skyWill most often do best of all
In an environment that experiences rain inthe morning fairly regularly, but that clearsup around noon with clear skies on into theevening, what would be the ideal direction(azimuth) relative to South for the array toface?
In an environment that experiences rain inthe morning fairly regularly, but that clearsup around noon with clear skies on into theevening, what would be the ideal direction(azimuth) relative to South for the array toface?The sun rises in the E, and sets in the W.The array should face towards an azimuththat is slightly west of south.This will allow for optimization of afternoonsun, after the skies clear.
S0ºE90ºW-90ºN-/+ 180ºA home has a roof that is shade free with anazimuth of 103º. Will this work for a solar array?
S0ºE90ºW-90ºA home has a roof that is shade free with anazimuth of 103º. Will this work for a solar array?Would this work?N-/+ 180º
S0ºE90ºW-90ºA home has a roof that is shade free with anazimuth of 103º. Will this work for a solar array?It wouldnt be good.N-/+ 180º
When does it make sense to havean array face North?For example, on the back side fo this house?
When does it make sense to havean array face North?In the Northern Hemisphere-NEVER.In the southern Hemisphere-ALWAYS.
http://126.96.36.199/nasa/module-3/why-does-temperature-vary/angle-of-the-sunDirect vs. Indirect Solar radiationwider area and more atmosphere to pass through
The angle of incidence is essentially the angle thatdefines how far you are away from a direct line fromthe sun.The larger the incidence angle, the less solarradiation/photons will strike the surface.solar altitude anglerelative to roof
Incidence angle: It is best to face thesolar rays for most direct absorptionof photons.Hence- arrays facing South, (NorthernHemisphere), TILTED at latitude.
blog.civitasenergy.comModule should be tilted so that the Incidence angle is at 90ºto the suns rays (set at tilt angle equal to latitude).If possible:Winter- tilt up 15º (Latitude + 15) because of lower solaraltitude angleSummer- tilt back 15º (Latitude - 15) because of greatersolar altitude angle
Incidence angle: It is best to face the solar raysfor most direct absorption of photons.Hence- arrays facing South, (NorthernHemisphere), TILTED at latitude.
Solmetric SunEye:More advancedshade analysisGPS built insoftware thatallows a shadinganalysis to becreated to shared
There are many smartphoneapps for shading analysis aswell:Sun Surveyor (android)SunSeeker (iPhone)(each app is about about $2 - $5)SolarPro article:iPhone Apps for Solar Geeks
Magnetic DeclinationEastern Declination Western declination
Magnetic Declination180 - (MD) = True SMAGNETIC Declination is theangle between the direction onthe compass and True South (orNorth.Compass needles is affected bymagnetic core of the Earth.*GPS devices preconfigured!*Change every few years,slightly.West Coast:+15º180º - (15º) = 165ºEast Coast:-15º180º - (-15º) = 195º
West Coast-western declination:+15º180º - (15º) = 165ºCompass tell you S is W of what itreally is.East Coast-eastern declination:-15º180º - (-15º) = 195ºCompass tell you S is E of what itreally is.
Mounting methods and locations:● Consider latitude● Consider tilt● Consider shadingBut also:Electrical service, system integration,placement of componentsOptions:roof mount, ground mount, pole mount
What is their vision and ultimate desire?● What is their motivation (selling points)● Determine energy usage andexpected/desired offset (size/$)● Do they want a roof or a ground mountsystem?● What are their preferences visually?Customer Assessment:
Energy usage and offsetEnergy Audit:http://youtu.be/YolBP0-vkBURecommend reductions in use ( highest valuefor customer / of system)Consider adding EA to your skills set as aninstaller/team or partnering with an AEcompany (value to installer)
Location and Visuals:Will primarily depend on availability ofshade-free area, but specific preferencescould play into decision.● Shading● Roof condition● Safety and code● Costs (and rebates)● Architectural appearance, aesthetics andcolor
Indiegogo Campaign:Online Solar School Developmenthttp://www.indiegogo.com/projects/online-solar-school-development?c=homehttp://www.indiegogo.com/projects/online-solar-school-development?c=gallery
Sarah Raymersraymer@solpowerpeople.comDirector of Education and TrainingServicesSolPowerPeople, Inc.NABCEP Certified PVInstallation ProfessionalCertificate #042013-107