Design and Feasibility Analysis of an on-Grid and Off-Grid System for Hospital Building: A Case Study on Dhaka Medical College

Abstract

Access to reliable and clean energy is essential for economic development, better healthcare facilities, building more equitable and inclusive communities, and being resilient against climate change. Intending to expand the use of renewable energy in Bangladesh, using an optimization tool named HOMER, we designed an off-grid and on-grid solar project at the rooftop of Dhaka Medical College and determined its economic feasibility. The load profile was calculated for 20 operation theatres(OT) and 50 wards of the old hospital building. The average energy consumption was found to be around 4454.6 kWh/day, with a peak load of 185.6 kW at a load factor of 54%. In the off-grid scheme consisting of solar panel, diesel generator, converter and battery, it is possible to generate 2,168,861 kWh electricity annually, out of which PV supplies 1,619,195 kWh (74.7%), and the rest, 549,666 kWh (25.3%), is supplied by the diesel generator. In this case, the NPC, LCOE and operating cost of the system are approximately 3,941,506 $, 0.179 $/kWh and 192,368 $/yr, respectively and the renewable fraction is 64.4%. In the on-grid scheme, formed of solar panel, converter and battery, a total of 2,548,458 kWh electrical energy is generated annually, out of which PV supplies 1,619,799 kWh (63.9%), and the rest, 928,659 kWh (36.1%), is provided by the grid. The NPC, LCOE and operating cost of the most optimized system are found to be 2,127,556 $, 0.06748 $/kWh and 96,460.62 $/yr, respectively. Here, the renewable fraction obtained is 58.1 %. Our analysis showed that while the on-grid is a cheaper option, the off-grid is a better alternative for generating a larger fraction of clean energy. A detailed sensitivity analysis has also been conducted to observe the effect of some variable parameters like discount rate, inflation rate, grid power price, diesel price and average solar radiation on the NPC and LCOE to achieve better insights into our work.