Maximizing PV System Performance with Single-Axis Trackers
←
→
Page content transcription
If your browser does not render page correctly, please read the page content below
Maximizing PV System Performance with Single-Axis Trackers Presented By: 6/21/2018 Speakers: Dan Shugar, Founder & CEO, NEXTracker Venkata Abbaraju, Senior Director of Product Development, NEXTracker Dustin Shively, Director of Engineering, Clenera, LLC Moderator: Scott Moskowitz, Senior Analyst, Solar, GTM Research
Audience Console
Speaker
Bios
Submit
Questions
Download Slides/
Additional
Resources
www.greentechmedia.com -1-
Today’s Speakers
Dan Shugar Venkata Abbaraju Dustin Shively Scott Moskowitz
Founder & CEO, Senior Director of Director of Engineering, Senior Analyst, Solar
NEXTracker Product Development, Clenera, LLC GTM Research
NEXTracker
www.greentechmedia.com -2-
Solar Tracker Demand Continues to Grow and Diversify
Global Solar Tracker Project Installations 2015 to 2022E, MWdc
30,000
25,000
20,000
Annual Installations (MWdc)
15,000
10,000
5,000
0
2015 2016 2017 2018E 2019E 2020E 2021E 2022E
Europe North America Asia-Pacific Latin America Middle East Africa Total
Source: GTM Research Global PV Tracker Landscape Report 2018
Trackers Will Also Continue to Gain Share Relative to Fixed Tilt Racking
Ratio of Fixed Tilt to Trackers Used in Ground Mount Projects Globally, 2015 to 2022E
100%
Percent of Ground Mount Installations
90%
80%
70% 63% 61% 62%
72% 68%
60% 80% 84%
85%
50%
40%
30%
20% 37% 39% 38%
28% 32%
10% 20% 16%
15%
0%
2015 2016 2017 2018E 2019E 2020E 2021E 2022E
Tracking Fixed Tilt
Source: GTM Research Global PV Tracker Landscape Report 2018
Tracker Shipments Jumped 32 Percent in 2013 to 14.6 GW, NEXTracker Leads the Market
Global PV Tracker Shipments by Technology Type 2015-2017 Global PV Tracker Market Shares by Shipments for Full-Year 2017 (MWdc)
100%
90%
Percent of Global Tracker Shipments
NEXTracker
80% Array Technologies
70% Soltec
Arctech Solar
60%
Convert Italia
50% PV Hardware
40% STi Norland
NClave
30%
Ideematec
20% Solar Steel
10% SunPower
Scorpius Tracker
0% Mahindra Susten
2015 2016 2017
All Others
Dual Axis Centralized Push-Pull
Centralized Rotary Drive Decentralized Auxilary Module
Decentralized Self-Powered
Source: GTM Research Global PV Tracker Landscape Report 2018
Take 15 Percent Off GTM’s Upcoming Events with Code WEBINAR
MAXIMIZING PV SYSTEM PERFORMANCE
Driving LCOE reduction through bifacial and smart system control
Scott Moskovitz, GTM
Dustin Shively, Clenera
Venkata Abbaraju & Dan Shugar, NEXTracker Greentech Media Webinar
June 21st, 2018
Copyright ©2018 NEXTracker
NEXTRACKER, A FLEX COMPANY
N. America
> 8.5 GW
An investment grade company
India & EMEA > 1.5 GW • $25B revenue
• $13B balance sheet
S. America > 1 GW
• > $400M free cash flow
Australia > 1.5 GW
Offices
Manufacturing: 175 MW/ week global capacity
13 GW trackers delivered globally
10 GW of Gen2 NX Horizon, zero wind events
Proprietary and Confidential ©2018 8
THE IMPERATIVE FOR ONGOING YIELD GAIN
• Scaling has driven PV CapEx ferociously, but much
of industry at unsustainably low margins
• Competitive LCOE most important driver in utility
scale sector
• Trackers , especially 1 axis horizontal, most optimal
for lowest LCOE 8minutenergy 300 MW Eagle Shadow: $23.76/MWh fixed
• Backtracking algorithms first introduced in 1991
• NX acquired machine learning company in 2016 to
accelerate next gen control strategy across its
platforms
“Backtracking: A Novel Strategy for Tracking PV Systems”,
Panico, Garvison, Wenger, Shugar, IEEE PVSC 1991
Proprietary and Confidential ©2018 9CREATING VALUE THRU INNOVATION & CONNECTIVITY
TrueCapture builds on prior NX technology including independent rows, self-powered smart
tracker, and data connectivity with NERP-CIP Compliance
Independent Rows Self Grounded Self Powered & Predictive Analytics & TrueCapture™ Smart
Balanced Tracker Tracker Smart Tracker Digital O&M™ Control System
Up to 93 modules, 1500V, Certified to UL 2703 & 3703 Eliminates AC power; Auto-commissioning, Using AI, machine learning
120° tracking range, standard, no need for integrated UPS, inclinometer, remote monitoring & and weather data,
15% N-S slope tolerance, & additional grounding motor current monitoring, & control of TrueCapture enhances
torsional limiter each pier components and labor wireless communications, system health; energy yield on solar plant
smart module NERC-CIP compliant and storage + solar
applications
Proprietary and Confidential ©2018 10REAL WORLD CONDITIONS CAN LIMIT PRODUCTION
Row-to-Row Height Variances
The World is Not Flat
• Terrain undulations
• As-Built construction variances
• Nearby geographic features
Diffuse Irradiance
• Overcast/ clouds
• Fog
• Heavy haze or pollution
Real-world project - diffuse light conditions
Proprietary and Confidential ©2018 11SHADING UNDER TRADITIONAL BACKTRACKING
Site w/ Variable Slope Morning and Afternoon Shading
Proprietary and Confidential ©2018 12ROW-TO-ROW HEIGHT VARIATIONS (undulation or
construction tolerance)
Proprietary and Confidential ©2018 13TRUECAPTURE CONTROL SYSTEM
ROW-TO-ROW TRACKING DIFFUSE TRACKING
TrueCapture eliminates shading losses
Proprietary and Confidential ©2018 14TRUECAPTURE ENERGY YIELD BENEFIT
Shade avoidance benefit Diffuse light benefit Shade avoidance
benefit
900
800
700
POWER PER MW (KW/MW)
Non-curtailment period:
600 Additional energy
generated during morning
backtracking
500
Non-curtailment
period:
400
Additional
Additional energy energy generated
300 generated when cloudy during evening
backtracking
200
100
0
4:48 AM 7:12 AM 9:36 AM 12:00 PM 2:24 PM 4:48 PM 7:12 PM 9:36 PM
TrueCapture Standard Tracking
Simulated example – one typical day on 1 MW site
Proprietary and Confidential ©2018 15TrueCapture Case Study: Perspective of a Developer, Owner, and Operator Dustin Shively, Director of Engineering Clenera Renewable Energy
Clēnera Growing Across America
Cost, efficiency, and team driving explosive
growth
• Acquisitions & Greenfield Development
• Asset Manager & Operations
• 630 MW-DC Installed Capacity
• 18 plants operating and in construction
• Over 1,500 MW-DC planned construction for 2018
& 2019
• 5 GW in development for 2019-2022Solar continues to grow in the SE
AL Solar A
• 111 MW-DC
• 1,100 acres
• Energy produced is equivalent to approx.
20,000 homes
• Energy solar to Alabama Power
• Connects to 115kV transmission
Due to terrain, some parts of the plant experience
row-to-row shading at certain times of the day.LAFAYETTE, ALABAMA – 115 MW
19Alabama 115MW DC Site: Representative Clear Sunny Day:
TrueCapture Generated 4.3% More Energy Production (R2R Only)
Lafayette Alabama Inverter Block 304
2.2MW AC Inverter | DC:AC = 1.45
2500
Morning
Afternoon
TrueCapture Gain
TrueCapture Gain
2000
DC Power (kW)
1500
1000
500
0
6:00 7:00 8:00 9:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:00
TrueCapture On TrueCapture OffAlabama 115MW DC Site 3-Month Period
TrueCapture Generated 3.23% more energy Production Overall (R2R Only)
16 18
TrueCapture Standard Tracking Cumulative Additional Energy
115MW Site | Alabama
MWh Additional Energy Generated per MW
14 16
14
5% 4.71 %
12 5%
MWh Energy Production/ MW AC
4% 1.48%
12
10 4%
TrueCapture Benefit
10 3%
8 3%
8 2%
6 2% 3.23%
6
1%
4 1%
4
0%
2 2 R2R (measured) Diffuse (estimated)
0 0
Days (Mar 15 to June 10th)TrueCapture Additional Case Studies & Benefits
Dan Shugar & Venkata Abbaraju
NEXTracker
Proprietary and Confidential ©2018 22CLIPPING VS. DC/AC RATIO TO TRUECAPTURE:
Clipping has almost no effect
Almost all TrueCapture gain occurs during off-peak time (during backtracking and cloudy conditions):
Row-to-Row Gain(Meas.) Diffuse Gain(est.)
6%
TrueCapture gain over Std tracking System
4.98% 4.90%
4.71%
5%
4.43%
1.48%
1.48% 1.48%
4% 1.48%
3%
2% 3.50%
3.42% 3.23%
2.95%
1%
0%
1.15 1.3 1.45 1.6
DC: AC Ratio
Proprietary and Confidential ©2018 23TRUECAPTURE BENEFIT: OTHER CASE STUDIES
Mississippi (74 MW): 3.5% More Energy 35
12
30
Additional MWh per MW (Cumulative)
TrueCapture Standard Tracking Cumulative TrueCapture Gain
10
25
MWh Generated per MW
8
20
6
15 D.E. Shaw Renewable Investments
Bryan Martin, CEO
4 10 Bloomberg New Energy Finance Summit,
April 2018 Presentation:
2 5
https://www.youtube.com/watch?v=G4czdUqBbRM
0 0
12.0 Oregon (14 MW): 3.9% More Energy 45
10.0
TrueCapture Standard Tracking Cumulative TrueCapture Gain
40
Additional Validations:
MWh Generated per MW
Additional MWh per MW (Cumulative)
35
• TrueCapture I.E. Report:
8.0 30
90% Complete
25
6.0
20
• Multiple New Projects
Financed with
4.0 15
TrueCapture
10
2.0
5
0.0 0
Proprietary and Confidential ©2018TRUECAPTURE BENEFIT WITH CdTe PV MODULES - TENNESSEE SITE
Ø Row-to-Row benefit currently not used
with CdTe technology
Ø CdTe technology yields more diffuse
benefit due to superior spectral response
Annual Diffuse only benefit % (Simulated)
1.8%
1.5%
Mono - Si CdTe
Proprietary and Confidential ©2018 25RESILIENCY FOR UNEXPECTED ATMOSPHERIC
DISTURBANCES
TrueCapture can reduce production impacts attributable to volcanic eruptions, fires, dust storms and El
Nino conditions by dynamically operating the PV plant
Wild fire impacts on PV energy production. Source: GTM
Proprietary and Confidential ©2018 26BIFACIAL HISTORY HIGHLIGHTS
• Japanese researcher H. Mori proposed bifacial in
1960
• 20 kW Solarex beta bifacial array at PVUSA in
1990
• Sanyo commercialized HIT for PowerLight in
2006
• PowerLight designed bifacial optimized trackers
in 2007
Proprietary and Confidential ©2018 272007: 14 MW NELLIS AIRBASE PV, LAS VEGAS, NV
• Largest PV in USA at time
• Included 2 MW Sanyo bifacial
• Used PowerLight T-20 Tracker with 2P
design, tilt
• Measured good bifacial gains of 12%+
due to low GCR and high albedo
• Visited by Pres. Obama 2009
Proprietary and Confidential ©2018 28SPRINGS PRESERVE BIFACIAL PROJECT, 2008
• Site is a Las Vegas area water history
museum; open to public
• PowerLight EPC & tracker manufacturer
• Horizontal tracker over tube with tilted PV
• White reflective fabric doubling as shade for
cars
• Up to 17% measured bifacial gains
PowerLight tilted 1 axis tracker over reflective fabric
with Sanyo HIT. Springs Preserve 2008
Proprietary and Confidential ©2018 29BIFACIAL CELL AND MODULE TECHNOLOGY TODAY
Industry Finally Moving Toward Bifacial at Scale
• Bifacial cells increasingly available & efficient
• Many PV manufacturers moving from Al-BSF to
high quantum efficiency designs with HIT, PERC, IBC.
• Cell enablers: high quality Mono, better quality multi
casting, thinner wafers, backside passivation and
texturing
• Module enabler: availability of 2 mm and 2.5 mm high
quality, durable low iron glass
Proprietary and Confidential ©2018 30NX HORIZON: CONCEPTUALIZED AS A BIFACIAL TRACKER
• One portrait design for maximum albedo
capture
• Modules suspended between Piers and
bearings
• Rails: Tall, short, and tapered away from
module, which is held OFF the tube
• Tube is round, 5” diameter, reflective
Testing rear tube effect at Center for Solar Excellence NEXTracker’s NX Horizon single-axis tracker
Proprietary and Confidential ©2018 31NX CENTER FOR SOLAR EXCELLENCE: ESTABLISHED IN
2013
• Technology showcase and R&D center
64 PV and inverter and battery technologies in field, four
different tracker manufacturers, 5 inverters, 4 battery types
• Testing facility
Extended lifecycle reliability, multiple storage technologies,
bifacial, thin film, linked & independent rows, fixed tilt.
• Training
NABCEP accredited installer training, PowerworX Academy
for customers and EPCs
• Bifacial
First tested in 2014
32
Proprietary and Confidential ©2018TORQUE TUBE IMPACT ON ENERGY YIELD
Module glass
For Standard Bifacial Modules Module frame
• 6.5% rear shade factor used in PVSyst
modeling
Torque
tube
• Optimized tube and mountain rail configuration
• Negligible back-side energy impact from tube due to
round profile, distance from module, and reflective
surface
• Measured annual effective ~0.5% energy yield loss due
to tube at NX test facility
Proprietary and Confidential ©2018 33NX HORIZON BIFACIAL GAIN UP TO 14%
4 years of field testing at Center for Solar Excellence, Fremont, CA (NX HQ)
Module A Module B
Month Bifacial gain (90% Bifacial gain
bifacial) (70% bifacial)
January ’17 5.99%
February ‘17 7.29%
March ’17 13.8% 7.34%
April ’17 14.0% 5.34%
May ’17 14.4% 4.99%
June ’17 13.1%
+13.8% +6.2%
• Comparison of bifacial gain for same cell technology from
each module manufacturer
• GCR 42%, albedo measured @ 18%
• Huawei 25kW inverters
NX Horizon with Framed Bifacial Modules Each MPPT was connected to a string of PV modules with different technologies
Center for Solar Excellence, Fremont CA
Proprietary and Confidential ©2018 34PVSYST NOW MODELS BIFACIAL + TRACKER
Factors influencing Bifacial yield:
Bifacial Gain on NX Horizon
• Albedo 10.0%
9.0%
• View Factor 8.0%
7.0%
• GCR (yield vs. land)
6.0%
Annual kWh boost
vs. monofacial
• Array Height (yield vs. structure cost) 5.0%
4.0%
• PV array height-to-width ratio
3.0%
• PV Bifaciality 2.0%
1.0%
• System DC / AC 0.0%
30% 35% 40% 45% 50%
Ground Coverage Ratio
35
Proprietary and Confidential ©20181 x PORTRAIT TRACKERS COLLECT MORE BACK-SIDE
IRRADIANCE
Hypothetical Scenario: Both trackers installed at same height
• Back-side irradiance function of tracker height/width ratio
96 W/m^2 74 W/m^2
Average back-side irradiance Average back-side irradiance
123 123
119 119
103 103
99 99
85 85
78 78
68 68
60 62
50 51
38
NX Horizon 2P Tracker
Proprietary and Confidential ©2018 361 x PORTRAIT TRACKERS COLLECT MORE BACK-SIDE
IRRADIANCE
Real World: Designed to clearance height 600mm
Horizon 2P
4,000mm
2,000mm
2,370mm
59% Panel height
1,500mm height-
75% Panel height to-width
height- ratio
to-width
ratio
NX Horizon 2P Tracker
Proprietary and Confidential ©2018 37PVSYST ANALYSIS: NX HORIZON vs. 2P TRACKER
Energy Production w/ Bifacial Panels 0.3%
NX Horizon vs. 2P Tracker
More
2,400 35%
Energy
2,395
30% vs. 2P
2,390
2,385 25%
2,380
20%
View Factor
Production
kWh/kWp
Back-Side
Specific
2,375 Modeled with PV Syst v6.72
15% • Blythe CA
2,370
• TMY3 weather data
• “Horizontal unlimited trackers”
2,365 10% simulation method
• 90% bifacial PV modules
• 20% ground albedo
2,360 • 40% ground cover ratio
5% • +/- 60° tracking range
2,355 • 1.20 DC/AC ratio
• 6.5% back-side shade factor for NX
Horizon
2,350 0% • 3.0% back-side shade factor for 2P
Low Elevation Standard Elevation High Elevation tracker
• Clearance = module edge to grade
@ 60° tilt:
• Low: 300mm
NX Horizon Yield 2P Tracker Yield NX Horizon View Factor 2P View Factor • Standard: 600mm
• High: 900mm
Proprietary and Confidential ©2018 38CLIPPING VS DC/AC FOR MONOFACIAL & BIFACIAL
Most of the bifacial yield occurs during mid-day, when inverters reach peak power
Bifacial Gain Monofacial Clipping Loss Bifacial Clipping Loss
15%
Percent difference w.r.t Standard MonoFacial on NX
10.01%
8.99%
10%
5.33%
3.62% 5%
2.69%
0.0%
-1.2%
0%
1 1.15 1.3 1.45 1.6
Horizon
-1.0%
-5%
-5.5% -5.4%
System:
• Desert Southwest Location -10%
• 35% GCR -11.0% -11.0%
• 30% Albedo
-15%
• 1P designed at 2’ clearance
-17.0%
-20%
DC: AC Ratio
Proprietary and Confidential ©2018 39NEXTRACKER RECOMMENDATIONS FOR MAXIMUM
YIELD
4 Low Profile Rail
1 1 Module in Portrait Tracker 3 30-40% GCR*
+ Round Tube
2 Framed
modules
5 7 Consider Storage*
6 ~1.25 DC/AC Ratio*
1.5M Array
Height*
Daily Production
w/ Bifacial Gain NX Flow
NX Drive
*Site & project variables impact optimal values Proprietary and Confidential ©2018 40FRAMED MODULES ARE BEST FOR TRACKERS
General Framed Advantages for Trackers:
• Faster installation time with less breakage
• Improved module reliability. Note: UL1703 is a static test, real world has dynamic loads
• No slippage and less risk of damage in high wind situations
• Thinner glass = less weight
• Long term durability; less breakage with site equipment, animals, ice/snow, sand dunes
Especially for bifacial:
• Enables safe mounting in portrait w/shared rail – no rails behind modules
• Avoid concentrating stresses on weak edges of module glass
• Short (400mm), low profile rail minimizes module edge shading
Proprietary and Confidential ©2018 41TRUECAPTURE + BIFACIAL: A WINNING COMBINATION
FIXED VS TRACKER
Monofacial Sp. Yield Bifacial Gain TrueCapture
BIFACIAL STUDY
2700
+3.5% Site Conditions
2500 Location: Desert Southwest
Specific Yield kWh/kWp
Albedo: 38%
+11%
2300
NX Horizon System
GCR: 35%
2100 Bifaciality: 85%
+22%
1900 +5% Fixed
Fixed Tilt: 25 degree
GCR: 60%
1700
Bifaciality: 85%
Fixed Tilt NX Horizon
42
Proprietary and Confidential ©2018Q&A
754 MW NEXTracker System
Villanueva, Mexico
Client: ENEL Green Power
Proprietary and Confidential ©2018 43You can also read
