Optimal techno-economic feasibility study of net-zero carbon emission microgrid integrating second-life battery energy storage system

Abstract

With the increasing adoption of variable renewable sources (VRE) and the deployment of electric vehicles (EVs) in the market, the share of harmful carbon emissions is reducing continuously. Forming a microgrid (MG) is the best way to integrate renewable energy sources (RES) to make a low-carbon path for electrification. Second-life batteries (SLBs), derived from the first-life application of batteries used in EVs, are lower in price as compared to fresh EV batteries and have sufficient remaining capacity as energy storage for MG applications. Therefore, to show the techno-economic feasibility of SLBs, this paper shows a comparative study of MG consisting of photovoltaic (PV)/floating PV/wind/biogas with fresh Li-ion batteries (LIBs) and SLBs. This paper analyses 4 hybrid models with fresh LIBs in off-grid and grid-connected mode, and based on HOMER-Pro an optimal model is finalized for the Asian Institute of Technology (AIT), Pathumthani, Thailand. From, six different cases of fresh LIBs, the optimal case is also selected by considering the lowest net present cost (NPC) and cost of energy (COE). With the significant amount of reduction in NPC and COE, the grid-connected hybrid models are found to be more economically viable than the off-grid models. The grid-connected optimal hybrid model is further analyzed with SLBs where a range of cost multipliers (CMs) and energy throughputs are considered as the sensitivity parameters for SLBs. The results obtained from HOMER-Pro show that the grid-connected optimal model with SLBs reduces the NPC and COE by 36% and 35%, respectively, compared to the fresh LIBs. Hence, the optimal system shows the lowest NPC and COE as, 4,136,254$ and 0.0411$/kWh, respectively, with the SLBs.