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 16 th,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 uncertainty of meteo input data solar radiation, meteo input plant layout, component data operation strategies performance simulation financial yield Solar Resource uncertainty: single highest source of uncertainty! (Ho & Kolb 2010) energy yield results
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 data like NASASSE,METEONORM,DLR-SOLEMI, SEC-NREL.
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 all SRRA stations are transmitted through GPRS to the CRS at CWET.
51 SRRA Location Map(Phase-I)
Instruments at SRRA Stations Sl No. Instrument Manufacturer Parameter /use A. Solar Measuring Instruments 1 Pyranometer (ISO secondary standard) Eppley Laboratory, USA Global Solar Radiation (W/m 2 ) (reachable uncertainty about 2 %) 2 Shaded Pyranometer (ISO secondary standard) -do- Diffuse Solar Radiation (W/m 2 ) (reachable uncertainty about 3 %) 3 Pyrheliometer (ISO first class) -do- Direct Irradiance (W/m 2 ) (reachable uncertainty about 1 %) 4 Solar Tracker Geonica, Spain For tracking Sun B. Meteorological Measuring Instruments 5 Ultrasonic Wind Sensor R M Young, USA Wind Speed (m/s) and Wind Direction (Deg) 6 Rain Gauge -do- Rain Accumulation (mm) 7 Pressure sensor -do- Atmospheric Pressure (mb) 8 Temperature & -do- Temperature(C) and Humidity(%) Relative Humidity sensor C. General Instruments 9 GPS Garmin, USA To synchronize Sun Tracker with Sun movement 10 Data logger & Modem Geonica,Spain For collection of sensor outputs, storing,averaging and transferring it to Central Receiving Station(CRS) at C WET, Chennai using SIM 11 GPRS Garmin, USA To transmit data through mobile SIM cards to CRS at C WET, Chennai 12 Solar PV Panel Moserbaer, India For charging battery for powering SRRA stations. 13 External Battery Exide, India For the electrical storage of SPV power. 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 (BSRN) rules by the World Meteorological Organisation(WMO).
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 DNI 0 = I 0 ε where I 0 : 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)
Error Error 18% 16% 14% 12% 10% 8% 6% 4% 2% 0% 18% 16% 14% 12% 10% 8% 6% 4% 2% 0% SRRA error statistics DNI: missing values (flag 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 DNI: coherence test (flag 5) Trichy Leh Pandharp GandhiNa Bilaspur Vellore Gurgoan Chilakap Bellary Rajahmun Belgaum Gulbarga Kadiri Medak Mandsaur Bijapur Tirupati Guruzala Rajgarh ChitraDu Neemuch 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 Most frequent shortcomings DNI: <- Missing values on average 2.3 % <- 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
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