Field Implementation of Photovoltaic-Battery Based DC Microgrid for a Typical School Load Application

In this study, a DC microgrid is proposed for a typical school load demand for the Roorkee, India location where the major load demand is electrical loads such as lighting, fan, RO water purifier. The other loads are the auxiliary electrical power supplies of the solar thermal unit which is operational at the site and used for the mid-day meal application. In the DC microgrid, solar photovoltaic (PV) is considered as the main power generator whereas battery energy storage medium is considered as the backup power source. PV power can be utilized, first to meet the required load demand and the excess power is used to charge the battery bank. In case, PV power is in deficit then the battery bank is discharged to meet the load demand uninterruptedly. In this study; firstly, a techno-economic analysis of off-grid DC microgrid with lead-acid battery energy storage has been performed using a hybrid optimization model for electric renewables (HOMER) simulation tool. Secondly, the proposed DC microgrid has also been implemented at a reduced scale at the selected site location. It is found that such type of DC microgrid is self-sufficient and efficient to meet the load demand uninterruptedly.