Solar Radiation Resource Monitoring

Click on Image To Enlarge

SGS Weather is the biggest Solution provider in the area of Solar Radiation Resource monitoring and research studies. With more than 135 online installed operational systems throughout the country, we thrive to provide the best solution to Solar harnessing project stake holder, research institutes and under bodies under India’s Jawaharlal Solar Mission.

The major challenge to harness the solar energy is first to know the exact location where maximum solar energy potential exists with necessary logistics without disturbing the eco system. We have large arid and semi- arid areas which is not used for any productive purpose. Most of them have large solar energy potential and can be used as life line to our economic development. However it is necessary to evaluate exact solar potential to ascertain the type of technology required and its economic viability. Before setting a solar power plant of any type (PV or CSP), it is essential to conduct thorough assessment of solar energy potential at the site. This information is the beginning of the technology process for setting up any solar power plant. Solar Radiation Monitoring SGS Weather

The basic station mainly constitutes of

Data Logger/ Data Acquisition System weather data logger

Our versatile solution of the Data Acquisition system is a 20 bit architecture designed for high accuracy sensors with customer existing SCADA connectivity through Rs 485 / 232 or RJ45 LAN connectivity. The data can be transmitted in real time to any location as per the requirement using GPRS, VSAT or Satellite Transmitter. The option of transmission of the data with the power plant is also available through OFC or CAT6 connectivity.

The extremely low power consumption allows to operate the system by internal batteries and a solar panel, as well as to connect, besides any additional meteorological sensor with the required Pyranometers and Pyrheliometers for the measurement and data transmission of the Global, Diffuse and Direct Solar Irradiance.

It is available in standard metallic enclosure. Another version is available in Compact mount Polyproplylene IP-67 enclosure ideal for portable and high humid environments.

Pyranometer for Global And Diffused We offer a complete range of Pyranometers from Hukseflux Netherlands for the measurement of Global and Diffused Solar Radiation. Hukseflux is a leading manufacturer of Pyranometers and other solar radiation sensors. These sensors are high quality instruments for solar radiation measurement, compliant with the latest ISO and WMO standards.

The different models of the Pyranometers offered by us are

pyranometers for solar radiation assessment

The most common considerations when choosing a pyranometer

Pyrheliometer for Direct Solar Radiation Pyrheliometers for solar radiation assessment

We offer high-accuracy direct (normal incidence) pyrheliometer with a short response time. The sensors comply with the specifications of the ISO 9060 standards and the WMO Guide. This is used with Sun Tracker mounted operation. Its fast response makes it very suitable for PV (photovoltaics) related applications.

It measures solar radiation received by a plane surface from a 5° full field of view angle. This quantity, expressed in W/m², is called “direct” solar radiation or direct normal irradiance (DNI). The sensor needs to be pointed at the sun by using a two-axis Sun tracker.

Besides its short response time, the sensor offers more advantages over competing models: DR02 window assembly is equipped with a heater which reduces measurement errors caused by (early-morning) dew deposition.

Solar Tracker or Shading Band We provide Sun Trackers for very precise solar tracking for automatic measurement of Direct and Diffused Solar Radiation. Two variants depending upon the requirement are available. Model Sun Tracker -2000 and SunTracker-3000

Solar Tracker-3000

Solar Tracker-2000

Both models are two axis fully automatic solar trackers, to align solar radiation instruments with the normal incidence of the sun, from any position on the earth's surface. They include a two axis mechanical device with two stepping motors with Stainless steel AISI 304 for worm and ring gears, which highly accurate than Inverted tooth belts , controlled by an electronic module combined with our Data Logger. Tracking control is carried out by an astronomical algorithm calculated by the data logger, having the possibility of integrating an optional GPS receiver for ensuring very precise clock synchronization.

This unique design has a fundamental advantage versus other solar trackers regarding the energy consumption, as model 3000 requires less than 3 watts and 2000 requires less than 2 watts from the battery of the data logger. So a single 75 W solar panel is good enough for powering both, the solar tracker and the data logger, avoiding the need of having 110/220VAC on the site.

SunTracker-3000 allows to mount one or two Pyrheliometers for the measurement of the direct solar radiation, as well as one or two Pyranometers with an optional support and shading assembly, for the measurement of both global and diffuse radiation where as SunTracker-2000 allows to mount one or two Pyrheliometers for the measurement of the direct solar radiation and one Pyranometer with an optional support and shading assembly, for the measurement of diffuse radiation

The operation of the Sun-Tracker in association with the datalogger allows profiting all the unique advantages offered by our versatile unit, as indicated below.

Remote communication with stations with wide variety of communication systems supported: GSM, GPRS, Wi-Fi, Fiber Optic, Ethernet, ISM Radio, RS232, RS485, USB, Satellite (Inmarsat & Insat), etc
Unattended and automatic operation.
Remote control of the solar tracker by means of the same communications network used with the data logger
Automatic transmission of SMS alarm messages in case of low battery or vandalism (GSM/GPRS optional modem is required for the logger).
Real-time calculation of the sun elevation and azimuth with absolute positioning each second
Clock synchronization via Internet time base or by an optional GPS receiver integrated with the data logger
Continuous recording in the logger of the sun elevation and azimuth .This allows correlating at any moment the direct solar radiation measurements with the sun position for subsequent data validation
Automatic and continuous diagnosis of the correct operation of the two stepping motors, in such a way that, in case of accidental error, an alarm message will be sent
Very low power consumption. This allows the logger to power also the solar tracker using a little solar panel for recharging its internal battery (mains is not necessary on the site)

Data Analysis and Archival Software weather data analysis and Archival software.png

We provide the latest generation of a software package developed by GEONICA for the interaction, configuration, data presentation, data analysis and real-time data monitoring of solar radiation stations. We offer the complete solution for customer requirement including connectivity to the existing or new SCADA system. Some of software standard features are

Remote communication with stations with wide variety of communication systems supported: GSM, GPRS, Wi-Fi, Fiber Optic, Ethernet, ISM Radio, RS232, RS485, USB, Satellite (Inmarsat & Insat), etc
Data storage remote request
Instantaneous data display on tables /charts
Request of images captured by the stations
Station configuration settings: time, channels, etc.
Calibration of stations and sensors
View real time data, statistical and historical charts and graphs
Reporting New virtual parameters from existing ones
Alarms display
Display of station’s status data on map with Latest data
Export of data in Excel and comma separated formats
Full customization of monitoring environment
Fully automated and unattended operations

Solar Reference Cell Solar cell inclined mount

Solar Reference Cell can be integrated with the Solar Radiation Station. The reference Cell is designed for calibrating the irradiance of solar simulators used for testing solar cells and modules. The Solar Reference Cells consist of a mono-crystalline silicon Photovoltaic Cell encased in a metal enclosure with a protective quartz window and a temperature sensor. The temperature sensor can be selected as either a Type K thermocouple or a 100 platinum Resistance Temperature Detector (RTD).

Solar Panel Surface Temperature

Solar panel temperature is one of the important factors that affect how much electricity the PV plants will produce. As solar panel temperature increases, its output current increases exponentially while the voltage output is reduced linearly. Since power is equal to voltage times current this property means that the warmer the solar panel the less power it can produce. The power loss due to temperature is also dependent on the type of solar panel being used.

Typically, solar panels based on monocrystalline and polycrystalline solar cells will have a temperature coefficient in the –0.35% to -.50% range. Lower temperature coefficient commercially available solar panels are the best performing for high temperature areas. On customer request, we integrate Pt-100SM temperature sensor in our Solar Radiation Station to provide panel Surface temperature in the data logger and their SCADA system.

We also provide complete weather station integrated with solar radiation measurement system as atmospheric parameters have direct affect on efficiency of Solar Panels/CSP system. Thus the atmospheric parameter correction are used for optimizing the solar plant functioning. Following sensors with fixtures are also offered.

Other Sensors which are optionally available with the Solar Radiation Station are Wind Sensor

3 Cup Anemometer with Wind Vane
R M Young Wind Monitor
Ultrasonic Anemometers

Temperature and Humidity Sensors

Air Temperature and Humidity sensor
Air Temperature sensor
Solar Radiation Sheild for RH/ Temp sensor

Tipping bucket Rain Gauge

Atmospheric Pressure sensor

Tower And Mounting

3 meter SGS Triangular MET mast, Galvanized with foundation bolts
Mounting for Pyranometer at inclined plane
Rain gauge mounting stand

Besides our standard accessories, we also tailor make and provide the system as per user requirements such as adding site camera, serial outputs, silicon pyrometers and all other customer requirements.

Benefits to Customers

Fully automatic Indoor Calibration.
Complete Data storage of calibration and automatic Calibrationin SGS Weather Solar Radiation calibration Lab.
Well established and traceable calibration methods.
Fast turnaround times .
Automated quality assurance of the measurement.
Suitable for all common Pyranometer models.
Indoor all-season calibration.
No dark environment required.
Indoor all-season calibration.
No dark environment required.
Calibration references available with us for many brands and models of Pyranometers.
OEM approved calibration facility.

SGS Weather Indoor Calibration Laboratory Pyranometer Calibration Procedure

We follow the instructions included in ISO 9847:1992 for pyranometers calibration. ISO 9847:1992 Solar energy – Calibration of field pyranometers by comparison to a reference pyranometer. The sesitivity of the pyranometer under test (the 'test sensor') is determined by calibrating this pyranometer against a reference sensor. This calibration method is described in ISO 9847 as a type IIc Calibration, an indoor direct beam Calibration. A reference pyranometer with a known sesitivity St in V/(W/m²) and a test pyranometer are placed side by side under an artificial light source. A shaded, an unshaded and another shaded reading are taken from both pyranometers, before the sensors are interchanged and the readings are repeated. A buzzer alerts the user when the sensors need to be interchanged, or when an error occurs.

The sensitivity Sr in V/(W/m²) of the
pyranometer under test is determined by

        St = Se (Vt + Vt’/Vr + Vr’)
        Where Vt = Vt, − Vt,
        Vtʹ = Vtʹ,u − Vtʹ,s
        Vr = Vr,u − Vr,s
        Vrʹ = Vrʹ,u − Vrʹ,s

With V voltage readings on the test (t) and reference (r) pyranometer, respectively shaded (s), unshaded (u), in original position (no apostrophe) or in interchanged positions (with apostrophe).

The shaded readings before and ater an unshaded reading are linearized to find the values for Vt,, Vtʹ,s, Vr,s and Vrʹ,s.

Voltage readings are taken on a Campbell Scientific CR1000 datalogger. Expanded uncertainty of the transfer itself is be calculated to be 0.5%. To find the uncertainty of the sesitivity of the test sensor, we include the uncertainty of the reference sensor itself and that of any corrections that are applied. Standard Calibration includes a measurement of the sensor resistance, the insulation resistance and the 95 % response time of the test sensor.

Various digital pyranometers are supported, with slight changes to the measurement protocol. The Calibration lab supports two different Calibration modes: side-by-side comparison and a single pyranometer mode. The Calibration includes various levels of quality control on input parameters and measurement results. The results are displayed on the Calibration Certificate.

Time taken by us for Calibration

2 working days after receipt of Pyranometer at our Calibration Center. Solar Radiation Sensor Calibration Download PDF Top

The basic station mainly constitutes of

Benefits to Customers

SGS Weather Indoor Calibration Laboratory Pyranometer Calibration Procedure

Time taken by us for Calibration

See Also in Our Key Solutions