Solar Energy / RSR100
RSR100 Rotating Shadowband Radiometer
Solar Resource Measurement System
Lower Cost / Lower Maintenance
weather applications water applications energy applications gas flux & turbulence applications infrastructure applications soil applications


The RSR100, Rotating Shadowband Radiometer, offers a lower-cost option for providing solar measurements, GH, DIFF, and DNI. The RSR100 system utilizes the fast response time of a Li-Cor photocell diode (10 μsec) coupled with the burst measurement (up to 2 kHz), control, and processing capability of a Campbell Scientific data logger to measure GHI and DIFF solar irradiance and compute DNI. An extensive range of additional sensors are available with the RSR100 for measuring meteorological and power parameters, such as wind speed and PV string performance. Reliable, low maintenance, low power requirements, and simple operation allow for long-term unattended remote solar resource assessment.

The RSR100 is built around Irradiance, Inc.’s RSR2TM Rotating Shadowband Radiometer. The RSR2TM is a second-generation instrument incorporating improvements in accuracy and mechanical reliability from collaborative research conducted at NREL, Sandia, and the University of Oregon Solar Monitoring Lab. Irradiance has manufactured over 500 RSR2TM units operating across six continents.


Most of the systems we sell are customized. These systems, however, typically measure the following parameters:

  • Global Horizontal Irradiance (GHI)
  • Diffuse Horizontal Irradiance (DIFF)
  • Solar radiation—plane of array (POA)
  • Direct Normal Irradiance (DNI)
  • Surface temperature—back of panel
  • Wind speed
  • Wind direction
  • Air temperature
  • Relative humidity
  • Barometric pressure
  • Precipitation

Benefits and Features

  • Contains a Campbell Scientific CR1000 Measurement and Control Datalogger
  • Provides a lower-cost and low power option for GHI, DNI, and DIFF solar radiation measurements
  • Fast to field with industry-proven design
  • Factory fabrication, programming, and testing minimizes field wiring errors and reduces deployment time
  • Complies with Modbus, DNP3, CANbus, and PakBus protocols
  • Supports nearly all communication technologies such as RS-485, fiber, TCP/IP, cellular, or satellite
  • Provides a battery back system that allows data collection during power outages and network failure
  • Supports Web Service API
  • Supports individual module soiling test and string level power performance