System Overview

Long term measurement of radiation balance is not only of great significance for studying weather and meteorology, but also helps to understand the Earth's climate system and the impact of human activities on climate change. The combination of ground radiation monitoring network and satellite radiation observations constitutes a complete global surface radiation budget assessment system. Ground radiation monitoring can effectively calibrate and correct radiation observations on satellites, providing long-term and effective observation data for global observations; Provide direct basis for the development of solar energy technology in both households and industries. Such measurements are essential for evaluating the theoretical analysis results of atmospheric radiation transmission, verifying climate model calculations, studying surface radiation change trends, agricultural meteorology, and ecological research. At the same time, the balance of radiation has significant value for research on evaporation, plant transpiration, and water cycling.

System principle

Radiation measurement is divided into solar radiation measurement and Earth radiation measurement.

The measurement of solar radiation, also known as shortwave radiation, can be subdivided into total sky radiation（Eg ↓) Direct radiation (S) and scattered radiation (Ed ↓) (note: Eg ↓=S+Ed ↓). When conducting budget measurement calculations, shortwave radiation also includes ground reflection radiation (Er ↑).

Earth radiation, also known as longwave radiation, is divided into downward radiation from the sky（El ↓) and upward radiation from the ground (El ↑). Income radiation (E ↓)=total sky radiation (Eg ↓)+downward sky radiation (El ↓); Expenditure radiation (E ↑)=ground reflection radiation (Er ↑)+ground upward radiation (El ↑). The difference between radiation income and expenditure is net radiation (E *), where net radiation (E *)=income radiation (E ↓) - expenditure radiation (E ↑).

Ultraviolet radiation is often measured separately, and the ultraviolet radiation that reaches the ground is divided into two categories:UV-A (315-400nm) and UV-B (280-315nm) monitoring of ground ultraviolet radiation and its quantitative changes is of great significance for strengthening environmental assessment and public safety. Therefore, WMO strongly recommends increasing monitoring of ultraviolet radiation for national UV index forecasting.

Our benchmark radiation station is based on the World Meteorological Organization's World Climate Research Program（Established in accordance with the requirements of the Ground Surface Radiation Reference Station Network (BSRN) under WCRP. As a radiation measurement benchmark in China, the reference radiation station can be used for calibration of other solar radiation data, meet the business needs of the national climate monitoring network, and meet the high-precision and high stability requirements of observation data. At the same time, the reference radiation station can not only serve as a model for general radiation stations and a base for radiation research in China, but also serve as a reference standard for evaluating existing radiation data, playing its due role in improving radiation observation work in China.

Reference radiation observations mainly include: total solar radiation, scattered radiation, direct radiation, reflected radiation, atmospheric longwave radiation, and Earth longwave radiation

Measurement of radiation such as ultraviolet radiation and photosynthetically active radiation. In addition, synchronous conventional meteorological elements will be added as needed. Strictly speaking, the measurement of direct and scattered radiation must be carried out using a solar automatic tracking system（Tracker）， Moreover, for radiation meters, it is necessary to strengthen the ventilation hood to maintain the relative stability of the probe's body temperature and remove any rain, dew, and fog that may accumulate on the probe.

System features

lIt can operate reliably for a long time from the early stage to the entire life cycle of the solar power plant, providing long-term reliable radiation data

l24/7 dual axis positioning, covering the position of the sun in the sky throughout the day

lFully automatic and independent operation, without the need for computer or human intervention

lHigh efficiency transmission system does not require maintenance

lbuilt-inGPS receiver, positioning and timing

lEquipped with a sun sensor for correcting tracking position, ensuring precise positioning and timely correction of small movements of the tracker caused by strong winds and vibrations

lsupportThere are two power supply methods, 24VDC and 90~264VAC. In the event of a short-term power outage, UPS can be used to ensure system operation

lWorking temperature support-The harsh climate characteristics of 40 ° C~85 ° C; Ventilation hoods designed for sandstorm weather can effectively reduce maintenance requirements and remove dust, dew, frost, and snowfall

lComplete programming and testing before leaving the factory to reduce on-site wiring errors and shorten debugging time

lMeets the standard requirements of the National Solar Energy Monitoring Network

lCompliant with the International Radiation Observation Network（Technical requirements for BSRN, International Meteorological Organization (WMO) standards, ISO 9060-1990 standards

lSupports multiple data transmission methods such as wired and wireless, allowing real-time viewing of observation data

lUsers can automatically adjust the measurement time and record the average radiation value, mean value of each measurement element, extreme value, etc. You can also customize the storage time and output various numerical values required by users

lAn inclined total radiation meter can be added to the tracker toThe efficiency of CPV and dual axis tracking planar solar panel systems has direct guiding significance

lThe sun position calculated by the tracker can be directly read on the data collector, providing control comparison basis for the tracking solar power generation system

lDesign referenceGuidelines for Solar Resources and Meteorological Engineering (Solrmap) and National Renewable Energy Laboratory (NREL)

system configuration

Application Cases

Inner Mongolia University of TechnologyIntroduction to Practical Cases of BSRN Reference Solar Radiation Station

Inner Mongolia University of Technology has installed our company'sThe BSRN benchmark solar radiation station has been operating normally for nearly a year, with good performance and accurate data, providing strong support for the school's scientific research in the field of solar radiation.

System Technical Solution Description

This system adapts to the business needs of the national solar monitoring network and meets the requirements of high-precision and high stability of observation data. Adopting traditional fully automatic solar trackers and solar positioning probes to achieve the international radiation observation network（Technical requirements for BSRN. Meets the requirements of the National Meteorological Organization (WMO) standards and the International Organization for Standardization (ISO) 9060-1990 "Specification and Classification of Solar Energy - Hemispherical Total Sunlight and Direct Sunlight Tables".

This system can accurately measure the total solar radiation, direct radiation, sky scattered radiation, sky longwave radiation, net radiation, ultraviolet radiation, and sunshine hours. At the same time, the system can monitor the total cloud cover in the atmosphere or the local cloud cover of different clouds. The solar photometer instrument of the system simultaneously obtains spectral data, including optical thickness, scattering coefficient, aerosol distribution, energy distribution, absorption rate through the atmosphere, and other parameters.

The system mainly consists of a data collector, direct radiometer, total radiometer (with forced ventilation hood), scattered radiation meter, ultraviolet radiation meter, wind speed and direction sensor, air temperature and humidity sensor, atmospheric pressure sensor, solar tracker, solar photometer, sunshine hours sensor, cloud cover radar, long wave radiation meter, net radiation sensor3-meter bracket (with various sensor brackets), system power supply, software, communication, etc.

Related case pictures

reference

1. Ren Yannan, Wang Zhimin, Guo Xiaotian Rui; Analysis of solar radiation data in Hohhot based on BSRN; Renewable Energy, Issue 01, 2016

2. Wang Jingjing; Design and research of BSRN solar energy data management and application system; Inner Mongolia University of Technology, 2014

3. Liu Aiming; Mo Jinghua; Zhuang Hongbo;; Design of Solar Radiation Observation Platform Based on BSRN Standard [J]; Guangdong meteorology; Issue 03, 2010