44
© Copyright 2013, First Solar, Inc.
© Copyright 2013, First Solar, Inc.
© Copyright 2013, First Solar, Inc.
Context
Soiling
Cleaning
First Solar Advantage
Context
3
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
First Solar at a Glance
Driving innovation across entire value chain and plant solution
Cost competitive with conventional energy sources today
Partner of choice for leading utilities and global power buyers
Over 8GW installed worldwide and over 3GW contracted pipeline
Founded in 1999 and publicly traded on Nasdaq (FSLR)
Strongest financial stability & bankability in the industry
5
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
TOPAZ SOLAR FARM
Largest investment grade renewable bond in history
6
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
AGUA CALIENTE
Reliable bulk power generation utilizing advanced plant controls and forecasting
7
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
COPPER MOUNTAIN 1
Co-located with existing gas combined cycle power plant
8
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
GREENOUGH RIVER
Displacing the energy requirements of a desalination plant
9
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
PHALODI
Providing energy security to India and displacing 1 million tons of coal
10
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
DEWA SOLAR PLANT
1st phase of landmark 1GW Solar Park in the UAE
11
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Power Conversion System (PCS)
Power Plant Area Potential Issue and Action
Inverter 1. Inverter installation should comply with Manufacturer high temperature application notes
2. Inverters may require canopy if above 45°C per published manufacturer requirements 3. There is significant potential for air recirculation from the hot air discharge port of one
inverter to the ambient intake port of the other and is also in proximity of the transformer radiator bank.
4. Inverter unit Heat exchanger design basis should be verified during design
Transformer Unit’s rating for degree rise should be factored in during design qualifications and verifications
Building and thermal management 1. The cooling design may not provide adequate cooling due to short circuiting of air flow to the exhaust fan.
2. Air intake for cooling should face proper direction to reduce fouling rate due to prevailing wind direction
3. Proper maintenance needs to be performed to verify if PCS filters are clean and not clogged to ensure proper airflow
4. Proper dust control should be ensure in sandy conditions
12
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Other Execution/ BOS items
Power Plant Area Potential Issue and Action
Mounting Structure 1. Corrosivity study should be completed prior to specifying coatings, hardware and other components
2. For large power plants the wind loads may vary between the outer rows and inner rows (also depends on fencing type); This needs to be considered during design of foundation, overhangs, and module height
3. Due to potential thermal gradients it is imperative that expansion provisions are provided on long structures such as beams, cable trays etc. that consider grounding/bonding impacts.
4. Wire management should be designed-in to ensure connectors do not get exposed to too much dust; Use of wire-ties capable of withstanding site extreme temperatures
Site Development Ensure sufficient sampling of geotechnical studies are done prior to design to ensure we capture all prevalent underground conditions and avoid unforeseen delays.
Site Construction 1. Proper & periodic dust control at site and inventory locations to ensure safe working environment
2. Warehouse and storage procedures should consider temperature onsite
© Copyright 2013, First Solar, Inc.
Context
Soiling
Cleaning
First Solar Advantage
Soiling
14
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Energy Conversion Losses from Light to Delivered Energy
LOSS FACTORS DESCRIPTION OF LOSS FACTORS Transposition on POA Irradiance gain due to module tilt Far Shadings / Horizon Irradiance loss due to horizon shading Near Shading on Global Irradiance loss due to row-on-row shading IAM Factor on Global Irradiance loss due to glass reflection & absorption Soiling Average annual energy loss due to soiled modules Spectral Shift Correction for AM1.5 spectral Non-STC Operation Energy loss due to operation other than at STC DC Health Energy loss due to DC array variability Module Mismatch Energy loss due to module manufacturing variability DC Wiring Loss Energy loss due DC wiring resistance Tracker wind stow losses Loss due to wind-stow of the tracker Inverter Efficiency Energy loss due to inverter efficiency Inverter Limitation Energy loss due to off-MPP tracking (clipping, etc.) Inverter Cooling Energy consumed by inverter cooling & heating Tracker Motor losses Energy consumed by the tracker motors and controllers Data Acquisition & Aux Daytime energy consumed by DAS and auxiliary loads MV Transformers Daytime energy lost in medium-voltage transformers AC Collection Lines Energy lost due to AC wiring resistance within the plant HV Transformer Daytime energy lost in high-voltage transformer Transmission Line #1 Energy lost in first transmission line to grid interconnect AC Interconnection Capacity Limitation Energy lost to control the output at the LGIA limit Utility Line Loss Credit Credit for energy lost in transmission line(s)
Light — Array Interactions
DC Losses
Inverter
AC Losses
Utility Interactions
15
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Proven Real World Performance Advantage vs. c-Si
All modules rated and labeled at STC
Additional First Solar energy for same nameplate power
16
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
First Solar Energy Yield Advantage
Temperature (°C) Instantaneous Power (kW) Accumulated Energy (kWh)
17
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Performance vs. c-Si in Hot Climates
Source: First Solar field array, US Desert Southwest, 2010 full year summary
• First Solar Has Energy Yield Advantage vs. c-Si Majority of Time
Firs
t So
lar
Co
nfi
den
tial
& P
rop
riet
ary
| ©
Co
pyr
igh
t 2
01
2
18
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
11%
12%
13%
14%
15%
16%
17%
18%
Poly-Si (STC)
FS New (STC)
11%
12%
13%
14%
15%
16%
17%
18%
Poly-Si (STC)
FS New (STC)
Poly-Si (60C)
FS New (60C)
Efficiency Roadmap Normalized for Temperature
2013 2014 2015 2016
19
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Observed Spectral Performance Trends
Diminished performance observed and predicted in dry winter months. Improved performance in wet summer months.
San Antonio, Texas, USA
PPI is temperature corrected DC power regressed to 1000 W/m2
Ontario, Canada
Blythe, California, USA
Improved performance during a 3-day thunderstorm system in the desert.
Improved performance observed in summer months with higher Pwat
20
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Monthly Soiling Level and Rainfall for Period of Record
• Average soiling level: 2.6%
• Monthly soiling level does not exceed 8.7%
0
0.5
1
1.5
2
2.5
3
3.5
4
0
1
2
3
4
5
6
7
8
9
10
No
v-10
Dec
-10
Jan
-11
Feb
-11
Mar
-11
Ap
r-1
1
May
-11
Jun
-11
Jul-
11
Au
g-1
1
Sep
-11
Oct
-11
No
v-11
Dec
-11
Jan
-12
Feb
-12
Mar
-12
Ap
r-1
2
May
-12
Jun
-12
Jul-
12
Au
g-1
2
Sep
-12
Oct
-12
No
v-12
Dec
-12
Jan
-13
Feb
-13
Rai
nfa
ll (m
m)
Soil
leve
l (%
)
Rainfall
Soil level
Published in the
January 2013
Journal of Photovoltaics (Vol 3. No. 1)
Data from utility scale installation in the United States
21
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Dust — Unique Concerns for a Unique Market
Primary Concerns:
• Accumulation of Soiling (energy loss)
• Surface Abrasion (‘sandblasting’)
• Ingress into sensitive electronic enclosures
• Shifting Sands
*Soiling is the 3rd most important PV performance factor, behind only insolation and temperature
22
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Soiling Factors
Mani and Pallai, Renewable and Sustainable Energy Reviews 14 (2010) 3124-3131
Factors Influencing Dust Settlement
Site Characteristics
(vegetation, traffic, air pollution)
Ambient Temperature and Humidity
PV System Tilt-angle and Orientation
(includes exposure to sun and wind)
Glazing Characteristics
(texture and coating
Wind Velocity
Dust Properties
(type, shape, size, weight)
23
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Field Images of Soiling Accumulation — DEWA Site
Day 5 6 7 8 9 10
Loss 2% 2.3% 2.7% 3% 3.3% 3.5%
Clean Module
24
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Kingdom of Saudi Arabia Demo Facility
Outdoor Test Facility at the King Abdullah University of Science and Technology (KAUST) in Thuwal, KSA as part of KAUST’s New Energy Oasis program (NEO).
Site Specifications
Commissioning Date July 2012
Location Thuwal, KSA
System Size 3.2 kWp
Avg. Annual Insolation1 2206 kWh/m2
Avg./Max. Module Temp2 49.6/70.8 °C
Annual Spectral Adjustment +2.6%
System Design
Module Tilt 20°
Azimuth 0°
Manufacturer SMA
Model SB 3000HF-30
Inverter Efficiency 95.46%
Module Type FS-380
Manufacturing Year 2012
1 Values determined using MeteoNorm 7. 2 Energy weighted average module temperature.
25
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
May Jun Jul0.7
0.75
0.8
0.85
0.9
0.95
1
1.05Energy Loss caused by Soil on PV modules
Norm
aliz
ed P
erf
orm
ance
PV System Performance
Soiling Impact on Energy
Direct measurements of soiling losses on PV systems
Soil accumulates when panels are not cleaned at a rate of ~13% power loss per month
System cleaned
Regular cleaning implemented
• First Solar’s ability to directly measure the impact of soil accumulation on PV modules can be used to evaluate the influence of soiling on PV system energy generation.
• This can be used in evaluating existing PV systems as well as predict soiling impacts on future PV plant energy generation.
Soiling impact measurement system
Caron, R., Littmann, B., Direct Monitoring of Energy Lost Due to Soiling on First Solar Modules in California, IEEE Journal Photovoltaics, Volume 3, Issue 1, January 2013
26
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Performance in the Kingdom of Saudi Arabia
Performance is within 1.0% of expectation
0
100
200
300
400
500
600
4/1/2013 5/1/2013 6/1/2013 7/1/2013 8/1/2013
Ene
rgy
AC Energy Generation
Measured
Expected
* Expected Energy estimate is generated by running the energy prediction model following First Solar’s guidance using on-site measured meteorological data as the model input.
27
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
-10.0%
-8.0%
-6.0%
-4.0%
-2.0%
0.0%
2.0%
4.0%
6.0%
8.0%
10.0%
0
500
1000
1500
2000
2500
3000
4/1/2013 5/1/2013 6/1/2013 7/1/2013 8/1/2013
Cu
mu
lati
ve E
ne
rgy
(kW
h)
Measured vs. Expected Cumulative Energy Generation
Measured Energy
Expected Energy
Difference (%)
Cumulative Energy Generation in the Kingdom of Saudi Arabia
Expected Performance Band
© Copyright 2013, First Solar, Inc.
Context
Soiling
Cleaning
First Solar Advantage
Cleaning
29
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Cleaning Solutions Portfolio
Low Cost High Availability
High Cost Low Availability
High Cost Low Availability
Low Cost High Availability
Robot Fleet
KAUST NOMADD
WATER WATER
LAB
OR
LA
BO
R Manual Dry
Brush Trolley
First Solar
Robot Fleet
Minimal Water
Manual
Wet Clean
Other Considerations:
• Night Cleaning Only
• Equipment Cost
• Plant Site Size
• Fixed Tilt & Tracker Structures
30
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Wet vs. Dry Cleaning
• Starting from heavy soiling, initial wet cleaning is required
• Regular dry cleaning can be used moving forward
Dry Cleaning Wet Cleaning
31
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Commissioning — Initial Wet Cleaning
• Heavy soiling due to construction traffic
• >2 months accumulation
32
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Heavily Soiled vs. Wet Clean — 500kVA Inverter Power Output Curves
• Data taken halfway through first cleaning of plant
• Illustrates maximum soiling loss after 2 months without cleaning
Clean Arrays
Heavily soiled
~35% loss
33
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Operational Cleaning — Trolley vs. Broom
Dubai is low-cost labor market with low water availability; two manual dry methods are appropriate:
Brush Trolley
• Double brush with suspension
• Requires two workers/unit
Dust Broom
• Velocity: 4 Workers = 1MW/night
34
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Operational Cleaning — Trolley vs. Broom
Trolley
• 2:20/240′ Row
• +3.9% PPI
Broom
• .25MW/man/day
Site Demo I (Agua Caliente, 6/13)
35
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Robotic Cleaning — Under Development
• 5:00/240′ Row
• Early Indications show PPI Improvements up to 9%
Site Demo I (Agua Caliente, 6/13)
36
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Case Study — Masdar City, UAE
Source: http://www.thenational.ae/news/uae-news/environment/dust-clouds-sap-uaes-solar-panels-power
System Size: 5MW
Installed: Jan 2009
Commisioned: May 2009
Developer: Enviromena Power Systems
Module Type: FS-272, 275
Inverter: SMA SC 500
"There have been several sand storms since the plant was commissioned earlier this year (2009) though this has been one of the longest…suspended dust in the air was between 1,500 and 2,000 parts per million - more than 10 times higher than normal”
- Khaled Awad, director of Masdar City (August, 2009)
A few field sample modules have been returned and initially observed for any surface abrasion impact – none detected
37
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Masdar City — 50X Surface Magnification
• Field modules sent to lab
• 50X Dino-Lite surface inspection
• No pitting observed under significant magnification after 18+ months
• Multiple sandstorms occurred during field deployment
Laser scribes between 2 cells
38
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
First Solar R&D — Optimized Tracker Algorithm
• Steep nighttime stow position reduces soiling accumulation 30%+
• Tracker position can be optimized for cleaning
Tracker #1: 45 degrees Tracker #2:
30 degrees
Tracker #2: 30 degrees Tracker #3:
22 degrees
Tracker #3: 22 degrees Tracker #4:
0 degrees
© Copyright 2013, First Solar, Inc.
Context
Soiling
Cleaning
First Solar Advantage First Solar Advantage
40
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
40
Series 3 Black
41
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
First Solar Series 3 Black PV Module
Reliability and Safety
Tested by leading international institutes and certified for reliability and safety
––Frameless
––Certified to IEC 61646
––Certified to IEC 61730
––Certified to IEC 61701 Salt Mist Corrosion Test
––Certified to IEC 60068-2-68 Environmental Testing—Dust and Sand
––FSEC Certification
––MCS Certification
––Thresher Test Certified
––TUV Long Term Sequential Test Certification
––CE Marking
––Safety Class II @ 1000 V
––Eligible CSI PV Module
––UL 1703 and ULC 1703 Listed Class B Fire Rating (Class A Spread of Flame)
42
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Samples — Potential Failure Mode vs. Test (PRM and Certification)
Firs
t So
lar
Co
nfi
den
tial
& P
rop
riet
ary
| ©
Co
pyr
igh
t 2
01
2
43
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Carbon and Water — PV Advantage
The only water consumption
during PV operations is drinking
water for workers and
kitchen/bathroom services
44
© C
op
yrig
ht
20
13
, Fi
rst
Sola
r, I
nc.
Takeaway
• Soiling is highly variable but not to be ignored in the Middle East
• Cleaning Methods are tailored to site specifics
• Water usage should be minimized
• Module Product Testing and Reliability Matters
• Frameless module gives better cleaning surface
• With proper cleaning regime, annual average soiling loss of <4% is realistic
• Data from lab-grade soiling measurement stations provides high confidence in energy predictions
