Battery Research in the Terschelling PV System

Abstract

With support from the CEC-DGXII and NOVEM, Ecofys has been conducting research into the Terschelling PV/wind/battery system (43 kWp solar generator, 75 kW wind turbine, 180 kWh battery storage) since 1987. The battery is one of the most vital parts for autonomous operation of the system. The possibility to use pilot cells in the control strategy deserves to be studied in more detail. If several banks are available, it seems to be possible to detect malfunctioning cells by comparing currents. If the battery consists of a single bank, voltage comparisons of parts of the bank may provide indications regarding the possible malfunctioning of cells. The battery has aged faster than anticipated. An important secondary effect of ageing is the increase of internal resistance and the unfavorable effect this has on the maximum power from the combination of inverter and battery.