## 3 Emission Reduction Measures at Ports
### Quayside and Yardside
We present the relevant solution measures to mitigate GHG in quayside and yardside areas from six solution categories below and summarise them in Table 6.  
The operational measures at quayside and yardside include berth allocation planning, quay crane assignment and scheduling, cargo loading and unloading, vessel stowage planning, internal moving vehicle scheduling, yard storage management, yard crane scheduling, container reshuffling/relocation, workforce scheduling, and coordination of equipment operations between quayside. The improved efficiency and productivity of quayside and yardside cargo handling equipment implies the reduction in fuel consumption and emissions. The vast majority of the studies on port operation optimisation belong to this category. A few survey papers, e.g., [32; 33; 34], have reviewed the literature on the applications of operation research techniques to optimise the port logistics processes, including ship stowage planning, yard storage and space allocation, crane scheduling, and internal moving vehicle scheduling. [PERSON] et al. [35] analysed two European ports, Hamburg and Genoa, and stated that an appropriate energy management system could coordinate and match port energy need and supply so that substantial energy efficiency can be achieved. [PERSON] et al. [36] simulated the energy consumption for container movements including unloading from vessels, inbound movements, RMG movements at yard, outbound movements, and loading onto vessel. An energy management system is presented to use renewable energy production by solar cells to reduce the peak energy demand. [PERSON] et al. [37] presented a unified framework to integrate the seaside/yard operations and the port energy system management for energy efficiency considering onshore power supply and microgrid. The technical measures at quayside and yardside include replacing and repowering older and dirtier diesel engines in ports, which was initiated by the US Environmental Protection Agency [38]. The Port of Koper deployed nine electrified quay cranes [23]. Rubber Tired Gantries (RTGs) could be modified to save energy consumption by utilising the regenerative power from the gravitational potential energy released when a container is lowered [39]. Converting traditional RTGs to electric RTGs has been applied in many ports and can achieve up to 64% GHG reduction [40]. Fuel and energy measures: A terminal operator in the port of Hong Kong was trialling the use of hydrotreated vegetable oil (HVO) in three types of cargo handling equipment: RTG crane, reach stacker, and empty stacker from October 2023 (www.portstrategy.com, accessed on 15 December 2023). Several UK ports have also deployed HVO as the drop-in fuels for port cargo handling equipment. In July 2023, RWE, Mitsui, and the Port of Tilbury formed a partnership to initiate a project to investigate green hydrogen for port equipment by switching from fossil fuels to hydrogen (www.forthports.co.uk accessed on 15 December 2023). Infrastructural measures: When the Port of Koper purchased nine electrified quay cranes, seven electrified RTGs, and three new RMGs in 2017, there was an infrastructure requirement of the 20 kV electrical network [23]. The use of low-carbon alternative fuels (such as HVO) for port equipment may require the rebuilding of fuel storage and distribution infrastructure [41]. The deployment of hydrogen equipment and its derivatives at port also requires building infrastructure to safely store and transport molecular hydrogen. Due to the continuous workloads, green vehicles (either electric or fuel cell) at quayside and yardside may have to visit the stations frequently [42]; this requires the installation of infrastructural stations for energy charging and refuelling. Another infrastructure measure is to re-design port layouts and facilities so that in-port travel distances can be minimised [23] and the efficiency can be improved.