In Bangladesh, poor power factors have been reported for medium voltage consumers which have large photovoltaic (PV) systems and participate in a net metering scheme. The current regulation establishes penalties for medium voltage consumers with low monthly average power factors, which might block invests in PV due to high costs for power factor penalties and the risk of even being disconnected. Then again, distribution grid companies were concerned the reactive power balance in the distribution grid might be disturbed by large scale PV systems.

The main objective of the study commissioned by Gesellschaft für Internationale Zusammenarbeit (GIZ) was therefore to analyse the impact of PV systems on the power factor of industries with net metering. Energynautics and project partner GOPA Intec examined the current situation where typically no reactive power support from the PV system is provided as well as cases in which the PV systems operate with different reactive power control modes.

In November 2020, Energynautics CEO Dr. Eckehard Tröster presented the results in a virtual meeting with representatives of distribution companies including West Zone Power Distribution Company Limited (WZPDCL), generating plant operators and Bangladesh Sustainable And Renewable Energy Development Authority (SREDA). SREDA is a Bangladesh government agency under the Ministry of Power, Energy and Mineral Resources, responsible for increasing renewable energy production in Bangladesh.

The study results indicated that there is no real issue on the reactive power balance when a PV system is operated in the distribution grid. However, the current procedure of metering the power factor was shown to be not very suitable with net-metering schemes.

Amongst other short and medium term measures, Energynautics recommended to change the algorithm to determine the power factor used for deciding on penalties. The power factor should be calculated based on the maximum demand (both kW and kvar). This method is internationally commonly used. It assures, that even in the worst case, the power factor of the load is compensated and allows for more freedom in controlling the reactive power of the PV system (e.g. for voltage control).

You can find the Q control study publication on the SREDA website.