Localised solar energy generation and storage for EV fleet charging

The thesis explores the feasibility of using solar energy and battery energy storage systems (BESS) for electric vehicle (EV) fleet charging at commercial depots. It analyses the techno-economic impact of using such a system. Additionally, it evaluates the environmental impact of the emissions released from electricity production to charge the fleets, also known as Well-to-Tank (WTT) emissions.
The thesis adopts a modelling-based approach to developing a solar model and an energy management algorithm (EMA). These models have been used to investigate the environmental and techno-economic impact of charging an electric refuse collection vehicle (eRCV) fleet based at a waste management depot.
Results show a maximum cost reduction achieved with a BESS of 0.5MWh when the eRCV fleet is split and charged at 11:00h and 23:00h, and the power capacity connection on site is not constrained. It provides approximately £1M in savings over the system lifetime of 15 years.
The maximum cost reduction for overnight charging is £530,000 with a BESS of 1MWh.
Greenhouse gas (GHG) emissions are reduced by 41 tons CO2 eq. per year with a BESS of 0.05MWh. When the power capacity connection is constrained, and the fleet is charged overnight, a BESS of 10 MWh reduces the excess capacity charge incurred by the site from approximately £0.8M to zero. However, it is still not economically feasible due to the high cost of installing a BESS. These findings contribute to establishing a body of literature that explores the use of solar energy and energy storage systems to reduce electricity costs and GHG emissions for electrifying road freight vehicle fleets. It explored the trade-offs between different PV energy systems, the building’s energy demand, different fleet charging strategies and the installation of BESS.
The thesis also provides insights for transport fleet operators regarding EV charging
management for maximising local solar energy generation and charging at a commercial depot. It supports operator and business decision making process regarding the installation of PV panels and BESS to charge an EV fleet, considering the system costs and benefits.