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SOLAR BIBLE GUIDE TO DESIGN / BUILD
Solar Electric Grid Tie Systems
ABC Solar
Featuring Technology by SolarWorld Americas Inc
SolarBible.com 2016
ABC SOLAR is an Authorized SolarWorld Installer
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ABC Solar Incorporated ABC Solar has been designing and installing solar electric grid-tie systems since 2000. We deploy our systems based on the best available solar and inverter technology. Each roof and home requires close attention to detail to maximize solar power and potential. We can source just about any solar panel, inverter or racking system. Our focus on high-quality and choosing the right system for each project. ABC Solar Incorporated (2000) 24454 Hawthorne Blvd Torrance, CA 90505 P: 1 310 373 3169 E: Solar@ABCsolar.com www.ABCsolar.com
Founded in 2000 and incorporated in 2001 Founder & President: Bradley L. Bartz California Licensed Contractor #914346 B-General & C-46 Solar
Copyright Š 2016 Bradley L. Bartz www.ABCsolar..com ISBN-13: 978-1503352490 ISBN-10: 1503352498
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Solar Quotation Worksheet
System Pricing Details
Client Details
Conduit / Wiring Distances:
Name:______________________________ Address:____________________________ ___________________________________ Phone:_____________________________ Email:_____________________________
DC: Junction/Combiner Box to Disconnect: AC: Inverter to AC DIsconnnect :
Energy Usage Details Utility:_________________ Acct #:_______________ Serv Acct #_____________ Meter #_______________ Kwh Usage:_____________ (Daily, Mon, Year) (circle) Project Details Main Panel Maker:_______________ Service Voltage: 208v, 240v, 277v, 480v 1 - 3 Ph Service Amps: 100, 200, 300, 400, 600 (circle) Sub-Panel Needed? Yes / No Roof Type:______________________ Roof Condition: Good - Ok - Bad Electrical Usage kWh KW Cost Jan _______-________-________________ Feb _______-________-________________ Mar _______-________-________________ Apr _______-________-________________ May _______-________-________________ Jun _______-________-________________ Jul _______-________-________________ Aug _______-________-________________ Sep _______-________-________________ Oct _______-________-________________ Nov _______-________-________________ Dec _______-________-________________ Summer Rates:______ Winter Rates: ____
$____________ $____________ $____________ $____________ $____________
___ft ___ft
System Price Rebate Estimate Cash Outlay Tax Credit Solar Investment Total
Steps to the Solar Installation Process 1. $1,000 deposit 2. Design permit package 3. Create rebate paperwork set 4. Create Net-Metering set 5. Once permitted: $___________ Parts Payment 6. Roofing and solar mounting feet are first 7. Inverter and conduit are placed 8. Solar panels are placed 9. City Inspections passed 10. Final Payment: $___________ 11. Work With Utility to put system in service. Solar Panel Choices SolarWorld (USA) Suniva (USA) Hyundai (KOREA) LG (KOREA) Mitsubishi (JAPAN) Solar Inverter Choices (SMA Sunnboy) SMA Sunnyboy with pigtail emergency power SolarEdge with Optimizers Enphase Micro Inverters Racking Choices Racking chosen specific to your roof and AHJ. Notes:
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The ABC Solar Installation Team Checklist The ABC Solar team is trained to look at each property and identify key standard items that are required in system design. The purpose of a thorough site visit is to accurately build a system that gets built to original design. This helps every stakeholder in the process feel comfortable, saves time and money. Our first checks are summarized as roof integrity and distance verification. The roof checks for spacing of the rafters. Most roofs are 16 inch on center with 2” x 6” timber. These are perfect for solar as they need no structural improvements. On the ground we are concerned about the distance from the proposed solar array to the main panel and our grid-tie connection point. We can be far, but the wire size has to be right to carry the current without significant loss. Conduit Location and Length: -Array to Inverter ________ft -Inverter to Service Panel ________ft This is key to size the wire to be ready for the amps and voltage of the solar panel array. Wire sizing tables that check temperature, amps and distance are used for this purpose. Please take these on-site photos ____ ____ ____ ____ ____ ____ ____ ____ ____ ____ ____ ____ ____
Roof types: Composition Shingle, Asphalt Shingle, Spanish Tile, Concrete Tile, Metal tile, Standing seam (Metal), Wood Shake, Ground, Flat (Ballasted OK, Not OK) •Roof Condition and age – please describe the roof and ask the owner how old it is. •Roof Orientation / Azimuth – which direction is the roof surface(s) facing? •Tilt of Roof from Horizontal – the tilt is critical in determining solar production. •Estimated Roof Surface Available for Array Draw Picture with measurements and photos •Shading - Draw a diagram, note any local shading (chimneys, vent pipes, antennas, gables, etc) •Placement - Draw Solar Array Location and Available Size •Note Roof Penetration Location: Interior / Exterior or Attic / Cathedral Ceiling •Utility Room Space for : - DC Disconnect__, Inverter___, AC Disconnect__ •What is the Main Panel Amp size? _________ amps. Are there open breaker spots? Yes / No
Overall views of site structure, fences, vegetation, gas, water, etc) Roof, multiple Main Panel from distance showing placement on structure Close up of Main Panel Inside of Main Panel to show breakers Main breaker Label inside Main Panel cover Truss/rafter tails Close up of roof tile Close up of eaves Vents or roof obstructions Possible shading problems Other concerns 6
Site Diagram
Scale: 1 cell =___Ft / Yd / Meter __ Not to Scale
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ABC Solar Incorporated - #914346 ABC Solar was founded in 2000. Over the years we have installed hundreds of solar grid-tie systems in California and Japan. Although this is not a huge number, it is a number that ABC Solar targets to maintain and we are proud of. We have 15 years designing and installing solar systems. We are licensed and insured. We do the solar work with our direct team and a team of great subconractors. All of our sub-contractors are professionals and are also licensed and insured. Our focus is on planning, delivery and customer service. We love our jobs. THE ABC SOLAR PROCESS 1. Energy usage history and evaluation 2. Roof / ground measurement for solar potential 3. Financial Analysis 4. Design and Permit Solar System - $1,000 fee 5. Payment for solar panels, inverters and racking 6. Install the solar system 7. Call for City Inspection 8. Final payment when pass city final inspection 9. Success and connect to the grid!
ABC Solar Incorporated is a B-General, C-46 Solar Contractor, design/build and supply company that has installed 350+ grid-tie solar electric systems in the Southern California area, California and Japan. These systems range from 2KW to 280KW DC in size and are interconnected to the SCE and LADWP grids. Our systems in Japan are generally in the 1 to 2 MW range. We do have some 25 MW solar farms under development. ABC Solar handles turnkey each of the following details for the client: System Design System Supply System Permitting System Installation System Testing I nterconnection with Utility System Rebating: Pre and Post System Monitoring and Maintenance Our teams continually attend solar training and industry events to stay up-to-date on solar technology. We are specialists with utility scale grid-tie to off-grid systems. We also study your project and come up with great solar solutions. You will see and learn that we love what we do. Our teams feel this way and you will love solar too.
The design process for solar is really focused on how much energy you use or expect to use and how much space do we have to install solar to solve that problem. We also look at solar applications like solar pool pumps and solar thermal water / space heaters. ABC Solar are experts in a wide variety of roof and ground mount situations. Focus is on designing beautiful solar systems that make as much energy as your property and utility will allow. This book will show you a wide array of solar install environments. Mostly our work is told in pictures, but some slides do have more written detail.
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Solar Grid Tie Systems
Your Electric Car as Your Home Backup System
Step 1: Total kWh usage/cost for last 12 months Step 2: Check roof/ground for space available Step 3: Make a proposal using proprietary tools Step 4: Send you proposal by email or in person Step 5: Send thank you letter and proposal Solar Battery Systems Step 1: Medical or business need? Confirm. Step 2: Battery systems are custom from $25,000. Step 3: Detailed battery system design and quotation are not free.
Our permit sets have been used as good examples by several Southern California cities. We have internal permitting notes and databases on local Solar Pool Heating Systems cities. Please see the end of this book for a sample permit set. Step 1: Square Foot area of pool? Step 2: Est. Gal. (width x length x average depth) The key consideration in permit rules is Fire deStep 3: Where is pool equipment? partment requirement of a 3’ clearance for access. Step 4: How many stories is the house? For big homes with many roof surfaces this rule Step 5: # of solar thermal panels (square area / 40) can be adapted and we can gain approval for our Step 6: Design rest of system and deliver proposal designs. Solar Hot Tub Kit Step 1: Do you want a UV Sterilizer? Step 2: Sell kit Step 3: Repeat
If we do have corrections we faithfully work with the city to advocate for maximum allowable solar system design.
PERMIT PACKAGES
WARRANTY - ABC Solar provides a 10 year warranty on installation. The Solar panels have these:
ABC Solar PV Permit Packages are counter ready. Our experience and focus is on working within the rules set forth by the city or homeowners association to allow for a smooth permitting process.
•5 to 10 year limited warranty on materials and workmanship •12 year limited warranty on 90% of power output •25 year limited warranty on 80% of power output
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Los Angeles Flower Mart 9 Different Roofs 1,280 Solar Panels
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We Are Peacocking! SolarWorld Installations by
ABC Solar Inc of California ABC Solar Japan KK
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The Cupola Solar Estate This custom home features 5 copper Cupola structures above a Spanish Tile roof. The Cupola design is carried thru the entire home to the layout of the pool. This solar grid-tie system features 30 Suniva American made 285 black on black solar panels. These connect to a SMA Sunnyboy inverter with an emergency use circuit. Panels chosen meet Palos Verdes Art Jury aesthetic black rules for solar installations. This system is expected to generate 11,609 kWh a year of free solar power! The Federal Tax Credit of 30% off the total system price was a good motivator. The Southern California Edison (SCE) excessive price for retail power is a main motivator and is the focus of the system investment value. Each Cupola houses 6 Suniva solar panels using a combination of S-5 clamps on the copper roof ridges (non-penetrating) and L-feet lag-bolted into support members and spanned with Uni-strut and SnapNrack solar racking.
Special thanks to the City of the Rancho Palos Verdes for granting our permit over the counter. It is always a pleasure to present unique designs to plan checkers and even better in RPV. The enthusiasm is infectious! The better part of the installation is drinking wine and laughing under the Solar Cupolas.
The design by ABC Solar is meant to please the original architect and his Jenga game block home.
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My compliments to the City of Newport Beach and the Crystal Cove HOA. This system features 42 SolarWorld SW285 panels to a SolarEdge 11 KW Inverter. The installlation of a new Solar Ready main panel allows the increasinng of this system to the lower roof. ABC Soolar stripped the roof, ourr roofer did a torch asphalt shingle roofing with our solar mounting team. The solar dance was epic.
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Hand Designed Hand Delivered Hank
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GROUND MOUNTED SOLAR SYSTEMS Ground mounted systems have three primary ways to attach or “grip� the earth. 1. 2. 3.
Ballast Mounted Racking Systems Schedule 40 steel pipe, holes and concrete Ramming steel i-beams or rebar into ground
Other methods do exist and we do seek them out when the ground conditions require creative solutions. The basic principle is to design the ground mounted system to be as far spaced as possible between each set of holes, poles and concrete. By using galvanized steel pipe we can have our base mounts 10 feet apart along the array of solar panels. The aluminum racking is then attached and prepared at the proper tilt for the solar panels and the wiring system. Ground mount array system design is focused on max tilt for production vs shade. This will always depend on the land we are installing on.
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Inverters and Electrical Balance of Systems The magic happens when the inverter takes the DC solar power and makes the conversion of the electricity to AC grid power. The inverter ranges in sizes for one panel each up to 2MW of solar panels connected to one unit. The micro inverter is known for shade tolerance and the ability to monitor each solar panel’s production. The string inverter is the industry workhorse and is used for all scale of system sizes. The Inverter has built in safety features that is increased by the installation of safety fused and un-fused disconnects before and after the inverter. All inverters have an anti-islanding requirement from UL and the utilities that when there is a blackout the inverter does not feed power back to the grid. This is a very important and needed safety feature to protect utility line workers who might be repairing the grid right above your home. Correction Factors for Ambient Temperature Below 25oC (77oF). (Multiply the rated open circuit voltage by the appropriate correction factor shown below.) This is for sizing string voltage.
Ambient Temperature (Co) Factor Ambient Temperature (Fo) 24 to 20 1.02 76 to 68 19 to 15 1.04 67 to 59 14 to 10 1.06 58 to 50 9 to 5 1.08 49 to 41 4 to 0 1.1 40 to 32 -1 to -5 1.12 31 to 23 -6 to -10 1.14 22 to 14 -11 to -15 1.16 13 to 5 -16 to -20 1.18 4 to -4 -21 to -25 1.2 -5 to -13 -26 to -30 1.21 -14 to -22 -31 to -35 1.23 -23 to -31 -26 to -40 1.25 -32 to -40
Inverters operate best at and are tested at 25 degrees Celsius. Each manufacturer has a VOC temperature coefficient that is typically seen at 0.003 to calculate for every 1 degree Celsius below 25 that voltage increase. The formula is: Number of solar panels *(Voltage+(voltage x (lowest temp - -25) x -.3/100)) = Operating Open Circuit Voltage. For Example in the US: 8 * (39.4 + ((7c -25c)*(-.3/100)))) = 362VDC. example 2, 13 * (39.4 + ((-7c - -25c)*(-.3/100)))) = 561.37VDC and in Japan we can go to 1000 VDC: 23 * (39.4 + ((-7c - -25c) * (-.3/100)))) = 979VDC. The easier way is to use the NEC 690.7 table for your inverter string system design. For 600 volt systems simple do max volts / (voltage * correction). 600 / (39.8*1.14) = 13.22. So each string can be 13 panels of the Solarworld SW275 module. Please note the table is more conservative and it is safe. Inverter location is also a key design choice. Generally we like them close to the solar panels AND the main electrical panel. But, we rarely get that luxury. We have to do the math for our wire size in terms of distance to voltage loss and amperage capacity Given the choice though, we would keep the DC run short and the AC run longer. This is because AC loses less voltage over longer distances with thinner wire. The thinner the capable wire the more money we save in copper and conduit. We use 10awg wire and ž� conduit for our residential installations.
The string inverter allows you to put in series a number of solar panels that will increase the voltage and thereby reduce the wire size needed to carry the current generated. In America the max DC input volts is 600 in the rest of the world it is 1000 volts or more. Solar panel voltage is affected by temperature, the colder it is the higher the voltage. The opposite is true for heat. 109
You can see the spacing of 10’ per steel schedule 40 pipe. The wood is used to hold in place the structure as the concrete dries. The depth of the holes is based on the slope of the ground. If it is flat then 3’ deep is generally acceptable. As the slope increases the downhill feet become progressively deeper to firmly attach to the earth the solar racking structure. The deeper you have to dig the longer it takes and the less “by hand” and more machine work needed for digging. This ground mount is being set up for 64 Sharp Solar Panels to two SMA SB8000US Grid-Tie Inverters. The Client recently added 8 more panels and that took him to grid-parity. He is making all of the energy he uses. The inverters were located right next to the array to make our DC wire run manageable. We trenched to 2’ deep and ran the AC wire in conduit to a safety disconnect switch. The system always has a dial meter installed by ABC Solar to be able to watch solar production in real-time. Once monitored we then connect to the main panel and spin backwards.
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Flat Roofs can be beautiful! The design is really shaped by the roof our team is presented with . Flat with no tilt is a good choice when you have cloudy or fog issues. This is because flat will capture the sun when it is ready. Tilted systems capture more sun power during the day for their azimuth and degree of tilt if it is always sunny. The LAGUNITA SOLAR ESTATE was built for the owner of Upperdeck Baseball Card manufacturing company. The 20 million dollar home construction included our 50 Sanyo Solar panel system. The roof mounts were put in appropriate places and then a thin layer of concrete was poured on by the roofer to seal and waterproof all penetrations. Since this estate is right on the ocean and only used 1 month a year, we designed a custom reverse-osmosis ionized water sprinkler system that keeps the system sparkling clean. The water feeds plants in the garden below. The sprinkler system was handmade, now the market has available kits.
The 50 Sanyo Solar panels are connected to two SMA SB6000US inverters that each fed one SMA webbox, a web-based solar monitoring system. This allows real-time web-based viewing of the solar production. Even empty this dynamic, climate controlled home used considerable energy keeping the interior environment perfect for the priceless items inside. The home felt like a holodeck on the starship enterprise. Any moment something fancy would appear. One floor surface lights up like a Michael Jackson video. We also used ABC Solar designed hinges to allow for look integrity and access to roof drains if ever needed for maintenance. The ABC Solar team worked with the City of Laguna Beach and the Laguna Beach Fire Department on every detail. Did you know the roofs are different in Laguna Beach?
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Flat Roofs Can pose a challenge as penetrations have to be done perfectly and more important are weight considerations. The weight determines the distance between the mounting feet and if roof support is needed. Flat roofs have a variety of materials and methods. Many commercial rooftops prefer non-penetrating solar mounting systems. The ABC Solar team are specialists at each type and present on these pages a small sample of our work on flat roofs. Tracking Systems – we are also experienced with single and dual access tracking systems that follow the sun. Depending on where you are on the planet tracking systems can increase your productivity by 40%. This is especially true in sunny California and less true in cloudy territories.
Flat installations, e.g. no tilt, are also effective in catching the sun when it happens on those cloudy days. Germany has proven that all directions catch sunlight. The tilt on flat systems is primarily dictated by design and energy usage profile. For example, if your most expensive electricity during timeof-use metering is between noon and 6pm then facing your installation west will increase your financial performance. If you want to level Peak KW demand then multiple directions might be best design choice. The Long Beach Rescue Mission This installation of 144 Solarworld 275 watt panels was paid for by a Port of Long Beach Green House Gas Reduction Grant. The Port made do
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ing the project easy for our small business to work with such a large organization. The 144 panels were connected to three Fronius 3-phase Inverters at 208v to backfeed solar. The racking system was custom designed with pre-tilted to 10 degrees mounting feet This allowed the rails to be bolted directly to the feet without having to use L-Feet. Saving time and money. It is projected that this solar system will feed 250,000 men over its 30 year initial life cycle. A key addition to commercial sites are Advanced Energy Storage devices. These are more than battery backup systremsthey actually allow peak-shaving to limit an agressive pricing scheme used by utility companies. Solar and advanced battery systems are the future to beat the monopoly utility demand KW pricing scheme.
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Flush Mount Systems The majority of our residential solar work is on gable or already tilted roofs. Determining the roof pitch is important to estimate solar production and the rebate value. Roof tilts to degrees are as follows: 1:12 = 4.76% 2:12 = 9.46% 3:12 = 14.04% 4:12 = 18.43% 5:12 = 22.62% 6:12 = 26.57% 7: 12 = 30.26% 8: 12 = 33.69% 9: 12 = 36.87% 10:12 = 39.81% 11:12 = 42.51% 12:12 = 45%
Composition shingles are the most common material for roofing. Generally speaking, the heavier the shingles are the more durable they become. The installation procedures calls for the same types of procedures used in the ABC Solar Spanish Tile method. Which is to strip the tile, lay 40 year comp shingle roofing and do our solar installation. Mounting feet are the primary component of a roof top solar installation. The feet are installed by a licensed roofer on all of our retrofit solar installations. The feet are mounted to house solar rails which will then hold the solar electric panels. The feet allow the rail 2' of over run on the ends and 4' to 6' between each mounting foot. Longer spans require stronger metal. With proper preparation our ABC Solar team then mounts the panels to create a clean solar energy installation. The lines are straight and the wiring completes the system. We work on all types of roofs: Wood Shake - Metal Shingle - Metal Pan - Composition Shingle - Concrete Tile - Reverse Tilt – Flat – Rock – Asphalt and Unique ones too. We are also experts at gripping the ground and use of ballast.
The first consideration for solar installations is picking the best roof to use for your system. Factors to consider are shade from trees and chimneys and the conduit run from the panels to main electrical panel or back-feed point. We will show you details from our clients solar installation pictures. Waterproofing Waterproofing is job #1 for any solar installer and is especially enforced at ABC Solar. We double check each penetration and attempted penetration and make sure we are caulking, fixing or replacing any needed roof material to do our job. We use standard roofing penetration waterproofing materials, which includes “Henry’s” and tacky tape. All retrofit roofing efforts are with our licensed roofer teams. Feeder Drill Holes Once the rafters and the layout of the feet are determined we will drill feeder holes to make bolting the feet to the rafter smoother, safer and stronger. 5/16” by 3” lag screws are used per mounting foot. Solar Rails Attach to Solar Mounts. The number of solar panels is calculated by width or height depending on if your installation is portrait or landscape (or a mis!). For example, we consider the Mitsubishi Solar 185 watt panel to be 33” by 66”, which is slightly bigger than their actual size to account for mounting parts. With the dimensions we can easily determine the best layout to maximize space use. Then the rails are drilled above each solar mount and then attached with washer and bolts. Many new attachment mechanisms are now available that allow plug-n-play connections and expanded variability. Our choices allow us to mount clean solar arrays on wavy roofs and sometimes be very creative.
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Waterproofing is JOB #1. Our focus on every installation is to waterproof each and every mounting penetration. Our 10 year roof leak guarantee is matched by our 10 year workmanship guarantee. Each solar mounting foot is attached to a roof rafter with 3� lag bolts. Each lag bolt is attached to a predrilled hole that is filled with roofing sealant.
The bottom of the mounting foot is also beaded with a sealant and then bolted into place. The skilled roofer then peals away the surrounding roofing shingle to slide and attached a flashing over the mounting foot. Once secured this completes the penetration waterproofing process.
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Spanish Tile: A Closer Look The ABC Solar Spanish Tile and Japanese tile mounting method creates smooth lines and increases air flow. By having 6 inches from the bottom of solar panels to top of the roof the panels also act as an effective shade barrier. We lay a 40 year composition shingle roofing in a terracotta color to be the waterproof layer for the solar roof. The solar mounting feet are installed inline with the new comp roof. The home gets two benefits: solar electrical power and a cooler roof. Can it get better? The primary reason behind removing the Spanish Tile from under the solar installation is weight. Old Spanish Tiles can weigh more than 14 lbs per square foot. The other reason to insure that we have a 100% waterproof installation. The feet are installed by our licensed roofer under the supervision of our solar tech’s lead. Careful removal of Spanish tiles and placement of solar mounting feet by our expert C-39 roofing contractor allows our installation team to place racking system rails as illustrated by the photo here. Feeder Drill Holes - Once the rafters and the layout of the feet are determined we will drill feeder holes to make bolting the feet to the rafter smoother, safer and stronger. 5/16” to 3/8” by 3” lag screws are used per mounting foot.
Waterproofing - Using standard roofing penetration waterproofing methods we finish the 1st part of our solar installation. Longer lag screws are used for certain roof configurations. Our ABC Solar standard for Spanish Tile roof is to remove the tile, lay a 40 year terracotta colored composition shingle roofing along with our solar mounts. Once the solar system is installed and we lace the Spanish Tiles for a complete look. The air space under array allows for better performance. The other reason to insure that we have a 100% waterproof installation. By removing the tiles we can see the real condition of the whole roof and do a better long-lasting job for our clients. Other contractors use “hooks” that allow them to ‘walk’ on your Spanish Tile roof, remove a tile, hit a rafter, mount, waterproof the foot and then replace the tile. We find this method is guaranteed to break tiles. 100%. Our experience and focus on customer satisfaction means every Spanish Tile Solar installation uses this ABC Solar method. Thier are exceptions to the rule, but not often. The focus is on a very long term quality installation.
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Commercial Solar The Los Angeles Flower Market - The Largest LA City Installation at the time. ABC Solar installed the SMA 225 grid tie SunnyCentral electrical inverter for the 280KW solar PV array of 1,246 Schuco Solar Panels. A Real Sunflower! Clean electrical conduit bends ensure system safety and efficiency. Our experienced C-10 licensed electricians handle the fine details, particularly for commercial installations. The larger wire and conduit require specific equipment and skills. This 280KW solar PV array is assembled with Prosolar racking, 1,246 Schuco 225 watt solar panels connected to a 250 KW grid-tie electrical inverter. The project is the first approved "lineside tap" project in the LADWP territory. Our backfeed point is after the meter, before the main panel. The project presented several unique design challenges which we were able to overcome through the combined efforts of our design, construction, and engineering teams. Specific issues came with racking and roofing on 9 different roof surfaces and styles. We used a combination of steel, aluminum and aluminum rail to create straight and true mounting platforms for our solar electric panels. ABC Solar prides itself on quality craftsmanship and design. Our crews are comprised of solid solar PV professionals and represent the talents and cultural diversity of the Southern California region. We have over a decade of design and build experience in the installation of solar PV and thermal energy systems. We will build the best solar system on your street. Commercial or Residential.
considerations is the span for the solar aluminum rails. Here we see new 4” x 4” sleepers being mounted to split-the-span on all of our flat roof tilt-racks. The sleepers are mounted to the roof rafters and then hot-mopped for waterproofing. The solar tilt kits are attached with L-feet and Henry’s roof goo for waterproofing. The fixed tilt racking on a dome shaped roof made many roof penetrations required for the panel racking system. The construction and design team faced rigorous attention to detail and assembly. The composition shingle barrel roof also dips slightly down the length of the solar array; however, by employing angled tilt legs and Prosolar racking, the ABC Solar installation team was able to ensure the tilt angle for maximum solar energy production by the panels. A pure South 180 degree azimuth and a 17 degree fixed-tilt. The straight lines of the solar panels add a sophistication to this downtown jewel. The 45’ lateral span of the array is secured by 2 and 1/2” unistrut steel. The multi directions of the roof required queer lines below to get straight lines above. The mounting brackets are Prosolar standard twopiece units. The available of 3” to 12” posts allowed some freedom from creative racking. Each mounting bracket is secured to the roof rafters by two lag bolts, then flashed and waterproofed. The Northside of the barrel roof posed two primary challenges. 1. Being far enough back to avoid shade contamination, and 2. Cross supporting and bracing for the reverse tilt on the Northside of the barrel.
Clean lines and precise angles with the racking system helps ensure panels may be attached quickly for a great looking and energy efficient solar array. One of the important design 117
POMONA SOLAR WAREHOUSE This Pomona Warehouse featured a brand new Thermoplastic polyolefin (TPO) single-ply roofing membrane that is basically form fit and melted to the roof. Our design team studied the warehouse roofing structure and determined best to lay 4” x4” wood sleepers to distribute the weight of the solar panel array. Once the 20’ length boards were laid out we drilled and bolted each to the roof. The contracted roofer, who originally installed the TPO roof, then form fit the TPO material to the sleepers and ‘welded’ them in place. Our solar design used a rail-less mounting system that ingeniously uses the solar panel frame as the rail. The cool thing was using less materials and a clean look. The hard part was having to be exact in our understructure. Other solar racking gives you a couple of inches of play to fix horizontal and vertical lines. This solar farm on a flat rooftop features 100KW of Schuco Nextpower Thin-Film solar panels.
The innovative Schuco racking system uses the frames of the solar modules as the rails of the support system. Each racking is in a set of 11 panels to allow for expansion of the metal during cold and hot and cold and hot. Solar PV panels and technologies are capable of producing significant amounts of energy even on partly cloudy days as shown here in Pomona. The amorphous solar technology also out preforms crystalline solar in high heat. ABC Solar Project Manager and Chief Installer is pleased with this solar PV project located in Pomona. On February 17, 2011 Mike was able to have the permit signed off! The other methods for flat roofs include standard mounting feet installation and ballast mounts. For flat roofs that we are penetrating we have the feet custom made with an 10 degree angle so we can attach the rail with limited hardware, saving time and money. Ballast mounting is very cool when the roof can support he extra weight needed to meet stringent wind load requirements.
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About Solar Photovoltaic Technology ABC Solar would like to take a moment to give a history of photovoltaic technology. Your system is the adoption of Einstein’s vision. Yes, Albert Einstein won the Nobel Prize in Physics for his explanation of how light (photons) travel 93 million miles to get in a fist-fight with the Silicon atom and how the photon “knocks-out” the silica electron. The knocked out silica electron is harnessed to make electricity. Solar Panels start in the ground as pure silica that can be mined. With one method the silica is treated with various chemicals to became ready to be melted. The melting process will get the silica into a molten state and head towards 1600 degrees Celsius. At this point a crystal is drawn thru the mixture and pulls up. This process starts the crystallization process of the raw silica into the usable solar wafer. The wafer is sized to typically 60mm and it is on its way to becoming a solar cell. Simply put a doping material is used to make one side of the silicon wafer positive and the other negative. A hair thin wire mesh is attached and leads are placed to allow in series connection of the cells. Now considered a solar cell, each just shy of ½ a volt DC. This magical number happens no matter how big the solar cell is. This phenomenon is not yet explainable by this writer, but I love thinking about it. The ½ volt DC of the solar cell is the building block of functioning solar panels. A 72 solar cell configuration is one of the most popular of the world’s solar panel manufacturers. 1/2 volt DC x 72 = 36 volts DC. This is the typical voltage range for a 72 solar cell solar panel. The 72 solar cells are connected to each other in series electrically. Lead free solder and silver wire are used by our preferred manufacturers. The sheet of solar cells are encapsulated to back sheets and framed to safety glass with long-lasting anodized aluminum. A power connection device called a Junction Box is surgically attached to the back of the solar panel and glued into place. Two wires
then extend from the Junction Box as positive and negative with quick connectors for ease of installation. Inverters: The SMA Sunny Central 250KW Inverter shown here provides 250,000 Watts AC Maximum Output Power and improved CEC efficiency of up to 96%. The inverter does the magic of changing the solar DC generated electricity to AC grid-capable power. The typical residential inverter will output at 240 volts open-circuit. This is routed in two 120 volt circuits that are then configured to safety disconnect switches and then backfeed to the main panel in 2x 20 amp breakers. Inverters input characteristics are key to understanding good and safe system design. The minimum and maximum DC input voltage and the other is the max amperage of each solar string. For the SB 7000 the input voltage range is 150 to 600 volts DC. The max amperage per string input is 18 at 240 volts. The Solarworld 275 Watt mono solar panel has an open-circuit voltage of 39.4. If we just divide 600 / 39.4 we would get 15 solar panels in one string. But! We have to take into consideration the local lowest annual temperature. The lower the temperature the higher the voltage. In the case of Los Angeles weather, the calculation is 39.4+((39.4 * ((-7c--25c)* (-.3/100))) = 43.18 VDC per panel. Now divide 600 by 43.18 and you get 13 panel max per string. A similar calculation is done on the highest temperature calculation. The higher the temperature the lower the voltage. So this high temp calculation is important for smaller string sizes to make sure you have the minimum 150 volts dc for starting the inverter. Solar electric systems perform better in cooler climates compared to the desert. The desert does have the advantage of many more days of full sun. Always a trade-off. 121
Mounting Hardware: To connect solar panels to the roof or ground various solar racking systems are deployed. Starting with rooftops the primary piece is the mounting foot. This device is attached to the rafters every 4’ to 5.5’ over the length of the array. The mounting feet either have one or two 3” lag bolts that are bolted to pre-drilled and goop filled holes in rafters. The feet come in various sizes from a low 3” to a high of 12” and sometimes taller. The height of the foot is part of the design process to determine tilt and is based on the roof. The mounting foot has a flashing placed on it that then becomes part of the roofing layer. The type of metal for both the flashing and mounting feet ranges from copper to stainless steel to galvanized steel. The choice for stainless steel is generally made in more toxic environments like right on the ocean. Sometimes design and color are the reason. Copper does age very cool. Once the mounting feet are in place the solar aluminum rails are attached. The attachment is done directly to the foot or is interfaced with L-feet that allow for flexibility in lateral and height adjustments. Double L-Feet can be used to create exotic tilts and lines. The solar panels are mounted to the rails using midclamps and end-clamps. These 1” wide machined parts are a bolt-down mechanism that hold securely the solar panels to the rails. The rail spacing is based on the requirement to not have more than 25% of the length or width of the solar panel hanging over the rail. Basic rail calculation is panel width +3” x # of panels x 2. So this array of 20 Mitsubishi panels at 33” each including spacing for mid-clamps will need (33”+3”)*(20)*2=1,440”. Rails are 20’ in length so we need 6 rails. TILT MOUNTING Tilt mounted designs are very common for solar arrays. For Southern California they best annualized for a fixed solar array is South at 17 degrees. Tilts of 40 degrees are common in Northern Japan. This is because of the height of the sun and to shed now.
Tilt mounts are common on residential roofs when we have to use the North facing roof. (if it was Australia the North roof would be great… but here in California…) Reverse tilt systems have very long rear legs depending on the slope of the roof. Basically city building departments will always require structural engineering if a tilt is taller than 18” above the roof surface. That is an important consideration when trying to keep costs down. BALLAST MOUNTING Many commercial rooftops are tenant buildings and these solar owners tend to prefer non-penetrating Ballast Mounting solar systems. The Unirac ballast Mounting System is well-designed and easy to install. Clean energy!
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Frequently Asked Questions 1. What is the most efficient Solar application?
4. Should I use a tracking system?
Two answers. For Solar electric systems water pumping is the most efficient. This is because DC motors are more efficient than AC motors. For solar thermal systems heating water is the most common solar application and by far the most efficient at an estimated 40% conversion efficiency.
Moving parts, so generally no. But, some applications it does make sense. In very sunny areas tracking can increase solar production by more than 40%. In cloudy areas flat is better to catch as much sun when it does happen.
2. What are the rebates and tax credits? The federal tax credit is 30% until 2016 then it will be 10%. Some utility and state rebates do still exist, but the price of solar has dropped significantly so the rebates are not needed as much anymore. The primary financial driver is how expensive is your utility company charging you per kWh. Please see www.dsireusa.org for up to date rebate and tax credit information state by state. Please contact us directly for information about the Japanese market. 3. How much does it cost and when do I break even? Commercial solar systems are breaking even in a little as 3 years. Residential is 5 to 11 years depending on how much utility company is charging. Southern California Edison is closer to 5 years.
5. What is the best panel orientation? Orientation Factor For Annual Energy Production in California - Source Endecon Engineering 6. Who invented solar panels? Albert Einstein won the Nobel Prize in Physics for his description of the Photoelectric Effect. According The Nobel Prize: The Nobel Prize in Physics 1921 was awarded to Albert Einstein “for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect”. From the opening ceremony of the Nobel Prize: “… Similarly, when a quantum of light falls on a metal plate it can at most yield the whole of its energy to an electron there. A part of this energy is consumed in carrying the electron out into the air, the remainder stays with the electron as kinetic energy. This applies to an electron in the surface layer of the metal. From this can be calculated the positive potential to which the metal can be charged by irradiation.
FACING Flat 4:12 7:12 12:12 21:12 Vertical South 0.89 0.97 1 0.97 0.89 0.58 SSE, SSW 0.89 0.97 0.99 0.96 0.88 0.59 SE,SW 0.89 0.95 0.96 0.93 0.85 0.6 ESE,WSW 0.89 0.92 0.91 0.87 0.79 0.57 E,W 0.89 0.88 0.84 0.78 0.7 0.52
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Only if the quantum contains sufficient energy for the electron to perform the work of detaching itself from the metal does the electron move out into the air. Consequently, only light having a frequency greater than a certain limit is capable of inducing a photo-electric effect, however high the intensity of the irradiating light. If this limit is exceeded the effect is proportional to the light intensity at constant frequency. Similar behaviour occurs in the ionisation of gas molecules and the so-called ionisation potential may be calculated, provided that the frequency of the light capable of ionising the gas is known.� --- I just love science! 7. How much power does 1KW DC of solar make? 1KW x 4 Sun Hours x 30 days = 120 kWh per month. The primary driver is Sun Hours. This differs by location. Ok, that is the simple way for us to calculate 1KW of solar production. Really it is the efficiency of the solar panels to the amount of watts in sunshine per 1 square meter. If a solar panel was 15% efficient and was 1 square meter in size it would generate 15% of the total sunshine value. In los Angeles sunshine is about 1,500 watts per square meter, so a 1 sq mt panel would generate 225 watts. 8. How much to power my 3,000 square foot home?
to make your electric bill close to zero. Another quick method is: a Solarworld 275 solar panel will make about 1 kWh per day. What is your daily usage? 9. The system size in kw is what? how is that calculated? The system size is in Direct Current (DC) watts. This is calculated using the nameplate DC watt rating from the solar panel manufacturer. 32 x 275 watts = 8,800 watts DC. Please remember that this is before the inverter does its magic and we get connected to the grid. It is typical for 15% to be lost and the AC watt number to be 7,480 watts AC. 10. My electricity usage offset would be what? Our general target is to make 100% of your electricity with solar panels. This means that your electric bill would be reduced to just a minor amount to stay connected to the grid. If we are building a smaller than usage system then each kWh is valued at what it would have cost you from the utility. Please note our experience is that consumers will start to use more electricity after they install their solar system. We don’t mind this at all, but it does make answering this question harder.
This depends on how much electricity you use. The average American home uses 500 kWh a month. If you have a pool, the pool is using about 400 kWh a month just to circulate and filter the water. Look at your electricity bill. Find the number of kWh you use per month. Divide that number by 120 (this is the average monthly production for 1KW of solar electric grid-tie panels). The result will be the number of KW you need to ma.ke all of your power by solar. For Example, if your kWh Usage is 900 kWh a month then 900 / 120 = 8.5KW DC You need approximately a 8.5KW solar system 127
11. Why is a centralized inverter being used over micro inverters? I am told they are less reliable, costly to expand (add panels), suffer from one panel being affected by shade or failure takes down entire system’s productivity. Educate me, I am not knowledgeable on this. The centralized inverter from SMA now comes with a 15amp circuit that allows you to use your solar power during a blackout. Micro inverters are for shade issue locations and folks that like to see production of each inverter. You to choose either the SMA with 15amp plug or micro inverters. Both types of inverters are very reliable. The centralized string inverter is usually designed to max capacity so expansion means a new system. 12. Are there other costs for me to be aware of? Like service panel impact, etc. The key item is your main panel size in amps, e.g. 200 amps. This determines the max solar system size that can be installed. If an upgrade to your electrical system is needed we will discuss with your utility company and get a price for that. Also, If there are free breaker spots then we just plug into those. If we need to add a sub-panel to backfeed then extra cost is about $500.
14. Who would I deal with for service issues? ABC Solar will handle all of your service issues. Please contact us on 1-866-40-SOLAR or Solar@ABCsolar.com 15. Permits included? No, Permit Fees, structural engineering or other fees are not included. Basic permit design is. 16. Is an allowance for climate patterns by scaling the system by some factor? That is a good question. In Japan we use 17 years of weather patterns to try and judge changes, but weather patterns are not what they used to be. In California we have the anal retentive California Energy Commission that has mesh data for every part of the state. We use www.CSI-EPBB. COM to access the CEC data with their solar production calculator. Just a point of clarification, the utility SCE carries out its solar production to the quadrillionth percent. 17. SMA inverter vs Enphase micro inverters: what would be the ease and cost to have to add a panels in the future on a SMA inverter system?.
13. Tell me about the PACE financing, interest rate and is it tax deductible, lien on my house?, can the term be adjusted to say 12 yrs, ownership of the system. PACE stands for Property Assessed Clean Energy – this allows you to finance energy improvements over 20 years and pay it back on your Property Tax Bill. This is the PACE funder we use. Please see https://heroprogram.com/ The term can be adjusted. You would own the system and keep the tax credit and any deductions. It is added to your property tax bill so you can consider it part of your tax lien. For commercial PACE see www.LApace. org.
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We could go up to a 7700TL inverter that would allow 8 new panels to be added. This way we would only be adding panels, racks and roofing. Some clients do have us build excess capacity in their string inverters so they can expand in the future. Mostly we try to right size from the beginning. Solar systems are limited by the size of the main panel in amperage. The National Electric Code (NEC) says we can only backfeed 20% of the size of the main bus bar. 18. I like the SMA feature of 15amp plug.could keep our beer cold during blackouts! How will this work? Basically we attach a 15 amp 1plug gfi box to the SMA Inverter. The box placement should be considered for ease of use during a blackout. (near kitchen…). I keep my beer solar cold today in my Solar Man Cave, but I digress… 19. Tell me what monitoring capability is provided for SMA? Generally there are 3 ways to monitor your solar system, but we can be creative:
20. If output were to drop, how would one tell what panel is at fault? First – we would check the voltage of each string. Each panel has a corrected voltage of 45.31 – we have 11 panels in each string so our DC voltage of a good string will be 498 volts. If the voltage is -45.31 volts then we know one panel is completely bad. (very rare). If the two strings of 11 do not match then the lower string will then be investigated for performance of each panel. 21. Can you please explain or send sketch/picture of mounting method, how many roof penetrations, what is the total additional roof load? How do we know the roof can handle it? Please see http://abcsolar.com/inst2-pg8.html and http://abcsolar.com/inst2.html This is a sample of what is used is our permit packages to describe the weight over the area of the solar array.
1) On the inverter is a simple power display (watts, volts, today, month ,etc). 2) The Sunnybeam -- this is a fist size blue tooth device. Gives you nice display of production and such. 3) The Webbox - this allows you to publish to a website your production data and thereby you can see from any where on the planet. 1) is free. 2) is ~$350 3) is ~$900, internet connection needed. For the most part #1 is fine. The solar system really will do the same thing every day. But, unless you walk by the inverter and see a red light, you won’t know it’s down until your bills go up.
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Roof Type: Composition Shingle Weatherproofing Method: Flashing Mount Make: Unirac-Flush Mount Total Weight of Solar Array: 1137 lbs Total Number of Attachment Points: 44 Weight per Attachment Point (b-c): 26 lbs Maximum Spacing Between Attachment Points on a Rail: 64 inches Total Surface Area of PV Modules (square feet): 397 ft2 Distributed Weight of PV Module on Roof (b-f): 2.86 lbs/ft2 22. Can you please provide a major events schedule with typical cycle times for project from start to finish. Just high level tasks. A. $1000 deposit - design and pull permit (allow two weeks)
As you can imagine our FAQ can go on and on. We encourage to ask more questions. Please email us at Solar@ABCSolar.com or call 1 310 373 3169. Thanks!!!
B. Equipment payment -equipment takes 5 to 7 days to land at your home-roofing and the solar mounting feet are done in one day -racking and electrical conduit is 1 to 2 days -inverter and final wiring 1 day -call for inspection 1 day C. Final payment due - once city approves, PGE has 30 days to turn on the system. 23. What is the required changes to my service panel, number and size of additional breakers? We will backfeed with a 40amp 2 pole breaker to your main panel. If space is available we just plug in. If older larger size breakers are there and your box is full, we can remove a couple of big breakers and replace them skinny ones. 24. Do I have to clean my solar panels? If it does not rain every so often it is a good idea to rinse off your solar panels. If you live near horses or trails you may need to rinse more often. We do design and install automated cleaning systems, just ask us! 130
SINGLE LINE DIAGRAM The Single Line Diagram is needed for construction and permitting. STEP 1: CHOOSE SOLAR PANEL Over the years we have installed solar panels made by SolarWorld, Sanyo, Mitsubishi, Sharp, Hyundai, and Sunpower. All of these makers have great quality control and good panels. In recent years our focus is on American made SolarWorld Solar panels. We do believe that the geometry of your space available will help us choose which panel. STEP 2: Number of Panels and the System Size In Southern California a Solarworld 275 watt solar panel will make approximately 1 kWh per day on an annualized basis. How many panels do you need to make your daily kWh usage? How many will fit? STEP 3: What is Lowest Temperature? What is the historical lowest annual temperature? Solar panels are tested at 25 degrees Celsius (77f) as this is considered their optimal operating temperature. Every 1 degree Celsius below 25 the voltage rating of the solar panel rises. The ratio is determined by the manufactures specification. STEP 4: Which Inverter? The Inverter choice is generally based on the overall system size. ABC Solar prefers inverters by SMA America for high quality and customer support. Other choices are between string and micro inverters. STEP 5: String Size? # of Panels in Series. Once the inverter has been chosen we determine the best string configuration for our system that meets the input characteristics. Voltage of the solar panel and temperature correction factor are considered.
STEP 6: Roof Type The city building department will want to know the age, type and number of layers of your roof. Also the rafter size and distance on center. Structural details for wind and weight calculations as required. STEP 7: What is the Hi-Temperature in Your Area? Just like low-temperature, Hi-temperature makes the solar panel DC voltage lower. This is important for small string sizes that get close to the inverter minimum input needed for daily startup. The higher the temp the less performance. STEP 8: Number of Wires in Each Conduit DC Side Two wires per string plus ground. Ex: 4 strings of 7 panels. 9 wires coming from the roof. STEP 9: Number of Wires in Each Conduit AC Side Each string inverter will have 3 wires, 2 hot and ground. STEP 10: Conduit Size The conduit size is determined by number of wires, temperature, amperage and local code requirements. STEP 11. Pick your Safety Disconnect Switches and PV Meter Once you have these steps done then you can create your single line diagram that is one part of the permit package set. Also, the utility company asks for the single line when the systems are big or they want to delay proceedings.
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Bradley L. Bartz Founder and Chairman ABC Solar Incorporated www.ABCsolar.com P: 1-310-373-3169 E: Solar@ABCsolar.com
Bradley L. Bartz Founder and Chairman ABC Solar Japan KK www.ABCsolar.jp P: 03-4578-9370 E: Sunshine@ABCsolar.jp
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ABC Solar Inc 24454 Hawthorne Blvd Torrance, CA 90505 1-310-373-3169 Solar@ABCsolar.com CSL# 914346 www.ABCsolar.com
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