Design Optimisation of Wind- PV-Microhydro-Multi-Energy Storage System for a Net-zero: Campus Case of University of Aberdeen Old Aberdeen Campus

Combined Heat and Power (CHP) units supply around two-thirds of the electricity that is consumed in the University of Aberdeen, s Old Aberdeen campus. As the CHP unit nears the end of its designed life., this paper explores the most cost-effective Hybrid Renewable Energy System (HRES) configuration that can replace the CHP and achieve the university , s emission reduction target. This paper first analyses the current CHP and grid energy system and presents the electricity demand and the equivalent carbon emissions of the Old Aberdeen campus. Then the potential for renewable electricity generation is explored which includes an assessment of the wind energy resources, solar irradiance, potential locations for solar panel installation on the University property, and the potential of micro-hydro installations on the river Don. The electricity demand and the renewable energy data are then used to find the most cost-effective HRES configurations for multiple energy scenarios using MOHRES software. The most cost-effective HRES solution in the context of the Old Aberdeen campus achieves net-zero electricity at an investment cost of 7.1 M£ which is paid back in 25 years with an overall energy cost of 0.18 £/kWh. This cost is 14.3% lower than the current cost of electricity supplied by the grid. The annual cost of carbon offsets that need to be paid between 2040 to 2045 to balance emissions from grid electricity using the recommended solution is projected to be around £35.,000.