Cross-climate analysis of techno-economic metrics in bi-level electrical and hydrogen storage systems for off-grid electrification of buildings
Aminhossein Jahanbin, Leila Abdolmaleki, Umberto Berardi
Abstract
Hybrid energy storage systems (ESS) are a viable solution for sustainable energy transition and decarbonization within the building sector. Nonetheless, the cost-effective design of hybrid ESSs remains a challenging issue, particularly for stand-alone buildings. In this context, the present study aims to provide insights into the cross-climate performance and techno-economic feasibility of a bi-level ESS driven by PV panels for off-grid power supply to office buildings. The hybrid bi-level ESS strategies incorporate electrical energy storage and two types of hydrogen storage systems, i.e., hydrogen-battery storage (HBS) and metal hydride-battery storage (MHBS) systems. To this end, a comprehensive techno-economic analysis of these systems is carried out under various climatic conditions according to the Köppen classification. A dynamic simulation model is established in TRNSYS coupled with a Fortran code, addressing the transient comportment of bi-level ESS strategies. A typical mid-rise office building is modeled using the OpenStudio-EnergyPlus plugin to simulate hourly energy demand in each climate. Adopting a statistical approach, a multi-objective optimization framework is developed to isolate the office building from the grid while minimizing hybrid system costs. The economic analysis based on the range-bar concept evaluates variations of techno-economic metrics triggered by alterations in the equipment costs within each quartile. The results indicate that the dry climate (zone B) has the lowest median (2 nd quartile cost) levelized cost of electricity (LCOE) for HBS and MHBS systems, at 0.097 and 0.192 $/kWh, respectively, followed by tropical one (zone A). Moreover, the levelized cost of hydrogen (LCOH) values range from 3.87 to 7.71 $/kg. Employing a predictive algorithm, the results imply that by the end of 2050, the LCOH for off-grid electrification of office buildings will be lower than 3.75 $/kg, regardless of the climatic conditions, having on average an annual decrement rate of 0.123 $/kg for all scenarios. • Dry climate shows the lowest median LCOE for both bi-level energy storage systems. • Gaseous hydrogen scenarios show on average 71.4 % lower LCC than metal hydride ones. • The LCOE in cases with metal hydride storage is more sensitive to climatic conditions. • Battery-metal hydride storage in continental zone is the most unfavorable solution. • The LCOH will be reduced by more than half within a 25-year period in all climate zones.