SRRA component of SolMap project
CENTRE FOR WIND ENERGY TECHNOLOGY
MINISTRY OF NEW AND RENEWABLE ENERGY
Presented by
Dr. Gomathinayagam
Executive Director
C-WET
April 16th,2013
CEM Multilateral Solar and Wind Working Group & IRENA work shop,
India Habitat Centre,
New Delhi
Accuracy of predicted energy yields
is
key for achieving project financing
Sources of uncertainty when predicting potential yields:
• technical risks: performance of components & their proper concert
• operational risks: realistic modeling of actual plant operations
• uncertainty of simulation models
solar radiation,
plant layout,
meteo input
component
• uncertainty of meteo input data
data
operation
strategies
financial yield
performance
simulation
energy yield results
Solar Resource uncertainty:
single highest source of uncertainty! (Ho & Kolb 2010)
Solar irradiation data availability in
India
•
IMD (India Meteorological Department) provided the “Handbook of Solar
Radiation Data for India” (A. Mani, 1980).
•
MNRE in 2008 updated “Solar Radiation Handbook” with the latest data for
the period 1986-2000.
•
Before SRRA ,very limited measured solar radiation data was available for
the country.
•
Other
sources
are
satellite
and
model-derived
NASASSE,METEONORM,DLR-SOLEMI, SEC-NREL .
data
like
Solar Radiation Map of
India
(NREL, 2010)
SRRA Implementation
•
Under Jawaharlal Nehru National Solar Mission(JNNSM-R&D), SRRA Program
was sponsored by MNRE in 2011 and implemented by C-WET, Chennai .
•
An exclusive SRRA unit has been established at C-WET.
•
51 SRRA stations in 10 states and 1 union territory have been established
between May 2011 to October, 2011.
•
Central Receiving Station (CRS) established at C-WET.
•
Data from
CWET.
all SRRA stations are transmitted
through GPRS to the CRS at
51 SRRA Location Map(Phase-I)
Instruments at SRRA
Stations
Sl No.
Instrument
Manufacturer
A. Solar Measuring Instruments
Eppley Laboratory, USA
1 Pyranometer
(ISO secondary standard)
-do2 Shaded Pyranometer
(ISO secondary standard)
-do3 Pyrheliometer
(ISO first class)
Geonica , Spain
4 Solar Tracker
B. Meteorological Measuring Instruments
R M Young, USA
5 Ultrasonic Wind Sensor
6 Rain Gauge
7 Pressure sensor
8 Temperature &
Relative Humidity sensor
C. General Instruments
9 GPS
10 Data logger & Modem
-do-do-doGarmin, USA
Geonica ,Spain
Parameter /use
Global Solar Radiation (W/m2)
(reachable uncertainty about 2 %)
Diffuse Solar Radiation (W/m2)
(reachable uncertainty about 3 %)
Direct Irradiance (W/m2)
(reachable uncertainty about 1 %)
For tracking Sun
Wind Speed (m/s) and Wind Direction (Deg)
Rain Accumulation (mm)
Atmospheric Pressure (mb)
Temperature(C) and Humidity(%)
To synchronize Sun Tracker with Sun movement
For collection of sensor outputs, storing ,averaging and
transferring it to Central Receiving Station(CRS) at C WET,
Chennai using SIM
Garmin, USA
To transmit data through mobile SIM cards to CRS at C
11 GPRS
WET, Chennai
Moserbaer, India
For charging battery for powering SRRA stations.
12 Solar PV Panel
Exide, India
For the electrical storage of SPV power.
13 External Battery
Besides these, data on Solar elevation angle, Solar azimuth angles, battery voltage etc are also being received in
Central Server at CWET, Chennai
CWET SRRA Station
Server 1
Server 2
A typical SRRA station
SRRA Data
SRRA Data Collection & QC
Sampling period
Averaging period
Duration
10 sec
10 min
Up to Nov 2011
1 sec
10 min
Up to August 2012
1 sec
1 min
From August 2012 till date
Data is being stored at multi location, processed and analyzed regularly.
For solar radiation parameters, the applied quality control is based on
Baseline
Surface
Radiation
Network
Meteorological Organisation(WMO).
(BSRN)
rules
by
the
World
SRRA QC data flow
SRRA Level 1
Raw Data
QC tests
Physical limits (radiation+ ambient air parameters)
Limits of a clean & dry clear sky condition (radiation)
Coherence between measurements (radiation)
Tracking Error (radiation)
Flagging
SRRA Level 2
QC’d data
report/data
product
generator
reports/data
products(monthly, annual,…)
SRRA QC test:
Physical plausibility tests for solar radiation values
Tests based on physical limits by Long & Dutton (2002),
with DNI0= I0∙ε
where I0: solar constant (1367 W/m²), ε: eccentricity correction)
SRRA QC test:
Check radiation maxima
against values for clean and dry clear sky conditions
Acc. Long & Dutton (2002)
SRRA QC test:
Test coherence between measurements
Acc. Long & Dutton (2002) and Long & Shi (2008)
SRRA QC test:
Tracking error test
Acc. Long & Shi (2008)
0%
18%
16%
0%
Amarsaga
Cwet
Santalp
Kota
Karaikud
Ramanath
Bodana
Mathania
Sirohi
Bhogat
Phalodi
Kayathar
Balotra
Jambua
Churu
Ajmer
Jodhpur
Keshod
Pokhran
Pondiche
Bagora
Vartej
Idar
KotadaP
Karad
Chandrod
Erode
Shegaon
Tharad
Sadodar
Trichy
Leh
Pandharp
GandhiNa
Bilaspur
Vellore
Gurgoan
Chilakap
Bellary
Rajahmun
Belgaum
Gulbarga
Kadiri
Medak
Mandsaur
Bijapur
Tirupati
Guruzala
Rajgarh
ChitraDu
Neemuch
Error
18%
Amarsaga
Cwet
Santalp
Kota
Karaikud
Ramanath
Bodana
Mathania
Sirohi
Bhogat
Phalodi
Kayathar
Balotra
Jambua
Churu
Ajmer
Jodhpur
Keshod
Pokhran
Pondiche
Bagora
Vartej
Idar
KotadaP
Karad
Chandrod
Erode
Shegaon
Tharad
Sadodar
Trichy
Leh
Pandharp
GandhiNa
Bilaspur
Vellore
Gurgoan
Chilakap
Bellary
Rajahmun
Belgaum
Gulbarga
Kadiri
Medak
Mandsaur
Bijapur
Tirupati
Guruzala
Rajgarh
ChitraDu
Neemuch
Error
SRRA error statistics
8%
6%
4%
6%
4%
2%
Most frequent
shortcomings DNI:
DNI: missing values (flag 0)
16%
14%
12%
10%
<- Missing values
on average 2.3 %
2%
DNI: coherence test (flag 5)
14%
12%
10%
8%
<- Coherence test
on average 3.6 %
Tracking error on
average only 0.7 %
SRRA data flow overview
SRRA Level 1
raw Data
QC tests
Flagging
SRRA Level 2
QC’d data
report/data
product
generator
reports/data products
(1 min, 10 min, 1h, 1 M, …)
Gap filling procedure
SRRA Level 3
gap-filled data
report/data
product
generator
reports/data products
(1 h, 1 d, monthly, …)
Availability of SRRA Data to public
•
Solar Data Policy is released and available in CWET web site
www.cwet.res.in
•
Freely available
• Interactive map of Previous month’s average for all stations
• Sample data in PDF-format for CWET SRRA station
•
On payment basis for all stations:
• Quality Controlled ASCII data and
• Reports in PDF format (Daily, Monthly and Yearly)
•
SRRA data distributed either through CD /e-mail.
SRRA Solar Data Policy 2012
•
MNRE, sole and exclusive owner of data.
•
Only quality controlled data will be sold.
•
C-WET is authorised to sell data. NDA to be executed.
•
Publication of data- requires specific MNRE/C-WET permission.
•
Data for >5 sites (bulk buyer) at a time requires Ministry’s approval.
•
Special approval from MNRE is required for supply data to foreign
nationals/institutions.
•
Details of pricing is available on www.cwet.res.in
ASCII data (1 min
average)
Monthly
Report(PDF)
Institutional collaboration with GIZ
SolMap project under Indo German Energy Programme
• data processing: quality checks, product and report generation
without & with gap filled continuous time-series,
• solar resource assessments with TMY creation,
• developing solar maps of India.
Possible further institutional collaboration
•
With IMD: Solar Radiation Calibration,
Data Sharing and Multi-location Storage
Systems.
•
Satellite data from ISRO, Ahmedabad
for the preparation of solar maps of India
•
Other providers of satellite-derived solar
radiation data.
•
Contribution to IRENA’s solar world atlas.
Figure 2 Spatial Distribution of Solar Radiation Monitoring Stations in the
Existing Network of IMD
1
SRRA Calibration Laboratory
High Level Solar Radiation Calibration Laboratory established at C-WET.
• Solar tracker with multiple thermopile radiometers.
• 2
Absolute
Cavity
Radiometers
for
traceability
to
the
World Radiation Standard.
Future Plans
•
Setting up of 60 more SRRA stations as part of the expansion program of
SRRA project to cover unrepresented states/UTs and also unrepresented
regions of presently represented states.
•
Aerosol measurements at 4 SRRA stations.
•
Calibration of solar sensors.
•
Upgradation and integration of 45 IMD solar radiation stations.
•
Consultancy projects.
Phase II- India Map
SRRA Stations - Phase I & II
Options for actions beyond SolMap as present
form
• Support SRRA phase 2: implementation, QC, analysis.
• Soiling correction of SRRA data.
• CSP benchmarking.
• Short-term solar forecasting for PV&CSP supporting grid operations and
CSP plant operations.
• Various radiation related data products.
• Grid integration of solar energy.
THANK YOU