STUDY ON INTEGRATION OF RENEWABLE ENERGY WITH PUMPED STORAGE HYDROPOWER

Abstract

Today many rural villages and remote parts of India do not have grid connected electricity supply. Although fossil fuels are being used to meet the power demands however raising concerns about environment and economic feasibility have questioned their sustainability and viability. Rising cost of electricity and environmental concerns are leading us towards sustainable and competitive source of energy. Renewable energy sources are intermittent in generating power since their meteorological parameters change continuously. Such power plants cannot generate electricity from wind and solar energies continuously due to intermittent availability hence require an energy storage device. Pumped storage system is the only viable, large-scale resource that is being broadly utilized today for storing energy, and it offers the best option available for harnessing off-peak generation from renewable sources. Pumped storage is flexible and has high energy storage capacity which helps in organization of other irregular sustainable power sources, for example, wind and solar energies. In pumped storage plants, major development is done on large scale plants however, in rural areas with small village load, small scale pumped storage plants are more feasible method for energy storage. The literature review highlights that most of rural villages in the country do not have continuous electricity supply. So hybrid system of solar and pumped storage can be feasible method to provide electricity in those areas. In Uttrakhand, Pauri Garhwal district has highest number of un-electrified villages. Rapidly increasing population and tourism in the district which is eventually increasing load demand of the area. There is good sunshine in summer and winter and also many feasible sites for construction of pumped storage in the area. Pumped storage site is, therefore, selected on Nayar River near 4 rural villages viz. Syunsi, Maithanaghat, Baijro, and Bironkhal. Solar PV data was analyzed in an hourly format for the year 2019 for the selected location. Load estimation of area is done on the basis of climate of the area, population, number of households, number of commercial buildings and day to day activities of people. According to load demand of the area, designed integrated system has solar power plant of 850 kW and small scale pumped storage of 550 kW. 2344 panels of 320 W are required to match the daily demand of the area having peak capacity of 850 kW. For the installation of 850 kW of solar power plant 8500 m2 of area is ii required. According to the requirement of system, Francis runner with radial flow impeller is selected as pump as turbine (PAT). Pumped storage works in pumping mode for 8 hours and in generation mode for 16 hours. Solar resource alone can suffice the electricity demand of the area. However due to its lower energy conversion efficiency and intermittent nature its integration with pumped storage is required. As per the analysis, designed scheme satisfies the domestic as well as commercial load demand of the area. Scheduling of solar pumped storage system is done on Python software. The financial analysis of system is also performed by HOMER Pro software which highlights the cost of energy of integrated power plant around 7.3 Rs/kWh.