## 6 Discussions and Research Opportunities
One main reason is that \"Each ship will use twice as much power as the rest of the port put together\" and there is a need for substantially more electrical power supply at the port to accommodate more ships simultaneously (www.bbc.co.uk, accessed on 5 January 2024). Thirdly, electrification and hydrogen-based fuels are essential to achieve net zero at seaports. Green hydrogen is produced via electrolysis, in which electricity is generated from renewable sources. Therefore, there is a big challenge in terms of generating sufficient electricity from renewable sources to meet the demand at seaports. According to DNV, the total electricity generating capacity for seaports could increase more than tenfold by 2050 (www.dnv.com, accessed on 5 January 2024). This is related to the issue of scaling up the production, storage, and distribution of green fuels. Liverpool City Region Combined Authority estimated that the hydrogen demand at the Port of Liverpool is 15 GWha. However, according to the British Energy Security Strategy, the low-carbon hydrogen production capacity in the UK by 2030 will only reach 10 GW (www.great.gov.uk, accessed on 5 January 2024). To fill the sizeable gap between demand and supply of green hydrogen is a worldwide challenge. One opportunity is to harness renewable sources on-site and near-site, as seaports are especially suitable for offshore and onshore wind energy and often have large capacity to install solar panels. On the other hand, renewable energies (e.g., solar, wind, wave, tidal) are often intermittent and variable in energy generation. There is a need to store the energy to match supply with demand over time. Currently, either batteries or hydrogen are viable solutions to store renewable energy. There are technological and logistics challenges in the management of green energy supply chains. Life cycle assessment and value chain analysis are needed for the fuel and energy solution measures. Fourthly, in most seaports, seaside vessel activities are the primary sources of emissions. Vessel decarbonisation has been extensively discussed in recent years. Port infrastructure is essential to support vessel decarbonisation by providing logistics service of alternative fuels to various vessels. Meanwhile, port hinterland industries are also facing the decarbonisation requirements, which may require alternative fuels from overseas producers through seaports. Therefore, a significant challenge to seaports is which type of alternative fuel facility should be constructed and at what time in order to be an energy hub to support the wider demand for alternative fuels. This challenge is further complicated by the fact that shipping companies are undetermined on which alternative fuel will be used in the future. Fifthly, digitalisation at seaports is still in its infancy. It faces both internal challenges, such as technical implementation for data collection and processing and technical skills and knowledge for data analytics, and external challenges, such as unwillingness to share information, technical difficulty of data compatibility, and concerns around cyber security and legal regulations. An incremental digitalisation approach is appropriate to tackle these challenges, e.g., starting with identifying the port's specific equipment or subsystem so that an easy-to-implement, low-risk digitalisation initiative can be developed with measurable cost-benefit ratio. In the long term, ports would be developed as data hubs. Sixthly, the maritime industry is facing high uncertainty of legal regulations and the lack of collaboration across stakeholders. For example, IMO has delayed the introduction of a carbon tax or levy for shipping emissions several times. Clearly, high carbon tax on shipping emissions would decrease the cost-benefit ratio of alternative fuels and accelerate the maritime decarbonisation process. Another substantial challenge is the financial consideration, because many solution measures for port decarbonisation require huge financial investment.