The Influence of Load Growth on Nepal's Distribution Network: Examining the Integration of Electric Cooking Stoves

In the present context, the government of Nepal is promoting the use of electric cooking stoves (ECS) over liquefied petroleum gas(LPG). With the use of ECS on a large scale, the distribution feeder load will increase significantly, resulting in a reduced voltage level at buses, increased loading on the distribution transformer, and, in fact, increased current carried by the feeder conductor. The study focuses mainly on the loading of the distribution transformer (DT), the voltage level at the buses, and the ampacity of the feeder conductor. The study is carried out considering two feeders: the Jorpati feeder in the Kathmandu district and the Malangwa feeder in the Sarlahi district of Nepal. The load and ZIP Coefficients of the study area are estimated by the polynomial load modeling technique based on a seasonal basis. The results show that the major impact is seen on the Jorpati feeder during the winter season. Considering the winter load and penetration of ECS at each household in the Jorpati feeder, there is overloading on 23 DTs. The existing dog conductor will not be able to handle the increasing demand for load current and the voltage level at buses drops slightly. Similarly, in the Malangwa feeder, the results show that the major impact is seen in the summer season. There is overloading on almost all the DTs except the private one, slightly low voltage levels at a few buses, and the existing feeder conductor will not be able to handle the increasing current requirement. Thus, system upgradation is required before promoting the use of ECS at each household in the Jorpati and the Malangwa area.