Design of an Ultra-Low Powered Data-Logger for Stand-Alone PV Energy Systems


  •   Asif Ur Rehman

  •   M. Tariq Iqbal


This paper presents an open-source, ultra-low powered data-logger for off-grid photovoltaic (PV) energy systems. Deep-sleep mode of ESP32-S2 microcontroller is used along with voltage, current, and light sensors for logging the data of PV energy system to an external micro SD card. A toggle switch is used to switch the operational modes of data-logger between deep-sleep and web-server modes. Real-time PV data can be monitored in a local web-portal programmed in the microcontroller. The same web-portal is also used to check and download the historical data of a PV energy system. The energy consumption of the designed system is 7.33mWh during deep-sleep mode and 425mWh during the web-server mode. The total cost of the designed data-logger is C$ 30.

Keywords: PV data-logger, open-source data-logger, ultra-low powered data-logger, Off-grid PV system, Renewable Energy, solar energy, ESP32-S2, PV monitoring System


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How to Cite
Rehman, A.U. and Iqbal, M.T. 2020. Design of an Ultra-Low Powered Data-Logger for Stand-Alone PV Energy Systems. European Journal of Electrical Engineering and Computer Science. 4, 6 (Dec. 2020). DOI:

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