Integrating 2MW Distributed Generation (DG) on 11KV Distribution Network of Nnamdi Azikiwe University

Abstract

Electricity distribution network in Nigeria is facing significant challenges; not been reliable, flexible, accessible and cost-effective. The technology of distributed generation (DG) incorporates energy systems (mostly renewable energy systems) to distribution systems that are close to the consumer load. Presenting distributed generation system, a 2MW hybrid solar PV/Battery/Diesel generator system installed at Nnamdi Azikiwe University. The study methodology is by modelling and simulating the university network with and without DG. The DG was connected to supply power via an underground cable to a ring main unit (RMU) used for switching between the grid supply and the DG. The university network with 59 bus bars was modelled and simulated while the supply was without DG (grid), and then while the supply was with DG on an average load of about 1.6 MW. Comparing the two systems, electric power generated is 1.565MW and 1.552MW for with and without DG respectively, while generation losses are 30.7KW and 44.1KW respectively. The voltage profile of the twenty-eight (28) 11 KV bus bar in the university network showed that with DG, 27 out of 28 bus-bars presented a higher voltage value than without DG which showed marginal range value for 27 bus-bars except for one (1) bus-bar. The 24 transformers sub-station installed at the university receives more power with DG since it generates more power than without DG. The analysis of the results obtained from this study has shown promising gains of the DG when commissioned to operate within the university community load of about 1.6MW.