19 AWS to monitor solar farms in South Africa

impianto solare in Sud Africa

The 75 MW plant is co-owned by a major local construction company and one of the biggest Italian players in the renewable energy market (the latest will also perform operation and maintenance activities of the plants). It is located in the Kalahari desert region, near the cities of Kathu and Sishen, in one of the world’s biggest open-pit mines.

When production will start in 2014, the plant will be one of the major one-axis PV plant on the planet. The total production capacity exceeds 146 GWh and the energy put on the national grid will be sufficient to satisfy the needs of 40.000 people, with a reduction of CO2 emissions in excess of 50.000 tons.

Thanks to his environmental monitoring expertise, LSI Lastem has ben chosen to supply 19 weather stations installed over the plant surface for an accurate control of the plant power production.

Each station is composed of a series of meteorological sensors used to calculate the plant Performance Ratio (PR):

  • Secondary Standard pyranometers (1 horizontal, 1 in the plane of the arrays) to measure total available solar irradiance;
  • High performance reference cells individuallly calibrated and with the same technology of the installed modules to evaluate PV performances;
  • Surface temperature sensors to measure junction temperature on the lower face of the modules;
  • Thermohygrometer with radiant screen to measure air temperature and relative humidity;
  • Combined anemometer to measure wind speed and direction.

Environmental data are sampled, stored and pre-elaborated by LSI Lastem data loggers with calculation of statistical indexes, totals, etc.

The data loggers are then polled by the plant controllers, produced and supplied along with the inverters by another major Italian company, via Modbus RTU over RS485 line to confront environmental and power production data.