Solar Resource Assessment MDI


Automatic weather stations specialized for DNI measurement (direct normal beam irradiance) are used for site analysis before and during project development as well as during operation of a solar power plant. For these different applications, and depending on the available maintenance and data transmission technology, different systems are available from CSP Services. They are adapted specifically according to client requirements with appropriate type of DNI sensor, solution of solar or grid power supply and connections for data transmission.

Irradiation Measurement

  • MDI station with Rotating Shadowband Irradiometer (RSI)

Optional Additional Sensors

  • ambient air temperature
  • relative humidity
  • barometric pressure
  • wind speed and direction
  • precipitation
  • visibility
  • soiling detection, etc.

Power Supplies

  • PV panel with solar battery
  • Grid connection with UPS

Data Transmission

  • Cell phone modem
  • Direct connection to plant control system

All our meteorological stations are prepared to provide highest measurement accuracy and maximum reliability. This is possible with the combination of high quality instrumentation and our operation and monitoring concept with daily data reception and continuous supervision of the sensors. An important influence on DNI measurement accuracy is soiling by dust in combination with humidity. Soiled sensors give too low readings, in particular in case of pyrheliometers (see graph for comparison) which are very sensitive to soiling.

Our services

  • Design and configuration of meteorological equipment according to client requirements
  • Installation and commissioning of the equipment on site
  • Daily data monitoring including data retrieval, check of correct equipment operability and data quality
  • Regular inspection visits on site, assistance in local maintenance
  • Data analysis and data treatment for enhanced accuracy, sensor soiling correction
  • Graphically illustrated summary reports on daily, monthly and annual basis
  • Full service for site-specific solar resource assessments, including evaluation of satellite data
  • Due diligence reports and expertise


  MDI station with rotating shadowband irradiometer
Application and purpose solar resource assessment (at remote sites without grid access)
DNI uncertainty single values: usually < 4 %
annual sum: usually < 2 %
(with proper calibration)
Required maintenance weekly to monthly supervision
Power supply PV panel and battery

Example Pictures

meteo mdi installed
MDI Station with Wind Speed Measurement
in Desert Environment
RSI rest-position
Twin Rotating Shadowand Irradiometer (TWIN-RSI)
MDI Station