The airline industry is growing and so are its emissions. To diminish the airline industry's increasing emissions, carbon-neutral growth for this industry is adopted. Sustainable aviation fuels (SAF) are considered an important aspect to comply with these goals and a large upscale of the SAF industry is needed. Therefore, the European Commission recently proposed a SAF blending mandate which mandates the uptake of this industry. However, the SAF industry is still a relatively new phenomenon and faces multiple barriers of which one of which is the divergent perspectives of the stakeholder groups within the airline industry. This research aims to identify the preferences of these different stakeholder groups. The following research question has been formulated for this purpose: "What are stakeholders’ preferences regarding different SAF technology pathways, in order to stimulate the SAF upscale for 2030 and comply with the proposed SAF blending mandate by the European Commission?" To answer this research question, a qualitative approach is applied. As such, a Multi-Criteria Decision-Making (MCDM) approach is used, where the Bayesian Best-Worst Method (BWM) is applied to determine the stakeholder group preferences regarding different SAF technology pathways. These SAF technology pathways are scored on economic, environmental and technological criteria. The stakeholder analysis shows that the airline industry deviates from the other three stakeholder groups (SAF/aviation experts, SAF consumers and SAF producers) as this stakeholder group attains more value to SAF its economic performance, combined with a decreased importance of both its environmental performance and technological performance. It is also concluded that overall, SAF its performance on greenhouse gas (GHG) saving emissions and its production volume availability and scalability are both deemed critical for a SAF technology pathway. Also, the expected minimum selling price is an important criterion in the analysis. Given the considered criteria and their perceived importance, regardless of which perspective of the stakeholder group is considered, the Fischer-Tropsch technology performs well due to its good performance on environmental aspects and its high production volume availability and scalability. As this research shows the divergent perspectives within the SAF industry, future policies could focus on finding consensus between these stakeholder groups.

Heavy-duty trucks (HDTs) are a significant contributor to global anthropogenic carbon emissions. In contrary to passenger cars, HDTs have to cope with decarbonization complications due to range and weight characteristics. Overhead catenary electric road systems (ERS-OC) can aid in decarbonizing this sector. Here, trucks are equipped with a pantograph and connect to catenaries on the highway, using electricity from the grid for propulsion. This technology complements other drivetrains and eliminates some of their major flaws, allowing HDTs to travel large distances with modest batteries or fossil-fuel consumption. Countries like Germany and Sweden have dedicated efforts and resources to ERS-OC as a carbon mitigation solution, and have multiple demonstration projects in use. However, this technology is lacking attention in the Netherlands, while emission reduction targets are closing in, and emissions keep rising.

Initiating ERS-OC activities through a demonstration project is determined to be a logical starting point in various countries. Identifying their perceptions is considered an essential step when aiming to implement an ERS-OC demonstration project. The aim of this research is therefore to answer the following research question: What are stakeholder-perceived factors that affect the feasibility of creating an overhead catenary electric road system demonstration project? This research is performed by conducting a qualitative case study for ERS-OC in the Netherlands. Nine interviews were conducted with organizations that have shown interest in the technology as a business opportunity. These nine respondents represent six out of the seven stakeholder groups that compose the ERS-OC system-of-systems. It has to be noted that no energy supplier was able to respond. Their perception of ERS-OC is therefore not considered during this research. The respondents were able to talk freely to avoid biases resulting from suggestive questioning, but the conversation was guided to other topics when necessary. The factors explaining stakeholder perceptions were extracted from the transcripts and coded to enable statistical analysis.

First, the perceptions of the individual stakeholder groups were analyzed. From the results can be concluded that the truck manufacturers mainly foresee implementation issues in the first years due to complications gathering investments. They think that when profitability is proven and the system will have shown it can play a vital role in decarbonizing HDTs, that upscaling will be just a matter of time. Freight operators are willing to engage, but need others to finance and construct the infrastructure, since they cannot afford to build infrastructure on their own. They are looking for the most cost-efficient manner to decarbonize their fleet, and it does not matter what technology that would be. The governmental entities acknowledge the potential of ERS-OC as a carbon mitigation tool, the huge reduction potential of electrifying the core highway network, and other advantages like decreased resource dependency, but await international developments to have guidelines on how to configure the system-of-systems, which explains stakeholder roles, responsibilities, and the interfaces between stakeholders,. They highlight that political acceptance of the technology is essential for the successful implementation of an ERS-OC network. Road power component producers highlight the unique capability of complementing other zero-emission drivetrains, and emphasize that ERS-OC should be considered as support for other powertrains rather than competition. They also consider it a cost-efficient measure compared to zero-emission alternatives, and say that ERS-OC is the only zero-emission technology that is currently implementable on a large scale for HDTs. There are few technical hurdles to overcome, proof of concept is present, but political urgency is lacking. Their biggest perceived barrier is a lack of leadership and priority with policymakers, and they think ERS-OC copes with an image problem. Standardization of catenary systems is considered key for the rollout of an international network. The construction firm sees the opportunity of bringing stakeholder groups together to create awareness and support base, and identify the lack of leadership as the main obstructing factor. Awareness among potentially involved parties is absent and increasing which could induce fast progression of ERS-OC implementation. The researchers state that ERS-OC seems expensive, but can have short payback periods, especially when compared to alternatives. Shuttle routes should be used when creating a demonstration project. They express concerns about power transfer issues when system occupation is high, and about the overall circularity of the system. They state further research is required before efforts and resources should be dedicated to ERS-OC.

The second sub-question investigates the perceived enabling and disabling factors for ERS-OC. Setting up policies stimulating engagement in ERS-OC is mentioned as a key enabling factor. The respondents state that they perceive configuring the system-of-systems as a significant challenge. Technological maturity is perceived as an opportunity that has to be exploited. Proof of concept is present and cost estimations are predictable, and there are few technical uncertainties. Catenary infrastructure can complement alternative powertrains, which is considered a vital enabling factor by the respondents. On the other hand, the possible technological breakthroughs of the other technologies is considered a disabling factor. On a political level, a decreased dependency on foreign resources is mentioned as an enabling factor, while the lack of political urgency to decarbonize HDTs in general is perceived as disabling. Economically, the potential cost reduction is an enabler, while the large upfront investment required is seen as an obstructing factor. The opportunity to lobby for a support base is frequently mentioned as an enabling factor. The emission reduction that can be achieved is mentioned often as an enabling factor of ERS-OC, a technology that complies with the ambitions of the organizations. However, the researchers mention that the circularity of the system as a whole should be furtherly assessed before conclusions on the overall environmental impact of ERS-OC can be made.

The last sub-question is dedicated to extracting the enabling and disabling factors that directly affect the feasibility of a demonstration project through the yes/no approach. Enabling incentives for organizations to engage in a demonstration project are that ERS-OC is a zero-emission technology that is considered sustainable. The opportunities that enable a demonstration project are technological maturity, setting up policies, lobbying for a support base, and using a shuttle route for the demonstration to ensure utilization. The perceived barriers to a demonstration project are a lack of leadership, vision, and perspective. This puts a risk on the significant investment that is required for the realization of the demonstration. The challenges that have to be overcome exist in configuring the system-of-systems, and gathering the investments required for the demonstration. Politically, the urgency to decarbonize HDTs has to increase, and ERS-OC has to be accepted by policymakers as a decarbonization measure before the demonstration project can take place.
Aggregating the findings of the three sub-question enables answering the main research question. The stakeholder-perceived factors that affect the feasibility of creating a demonstration project are divided into internal and external factors for the organizations. The incentives that positively affect the feasibility of creating a demonstration project, according to stakeholders, are organizational ambitions, political urgency, the need for electrification, the societal pressure on decision-makers, and the opportunity for stakeholders to generate more business by entering new markets. The opportunities, perceived by stakeholders, that positively affect the feasibility of creating a demonstration project are the technological maturity, lobbying for support base, creation of enabling policies, the proof of concept that shows the functionality of the technology, and creating a test site or game to familiarize stakeholders with the technology and their future role and responsibility. Starting with a shuttle route and gradually expanding the network is an opportunity that needs to be kept in mind when choosing a location. Stakeholders can take an early advantage when engaging in the demonstration project, and green investors that aim to gain profits from the sustainability trend can be attracted when struggling with financing the project. The stakeholder-perceived barriers that negatively affect the feasibility of creating a demonstration project are waiting for international developments to provide an example, a lack of leadership, a lack of vision and perspective, absence of incentives to engage in ERS-OC projects, the lack of consequences when emission agreements are not met, the magnitude of investment that individual organizations have to make, and the risk of losing that investment when the technology will not become successful as an HDT decarbonization measure. The challenges that might negatively affect the feasibility of creating a demonstration project are mainly political. Setting up the system-of-systems that explains stakeholder roles, responsibilities, and interactions is required before a demonstration project can be set up. An attractive business case that is profitable for all involved parties needs to be composed before the required suitable partners can be attracted. It is essential that ERS-OC is politically accepted as a decarbonization measure, and that the political urgency is present that allows for the required resources to be released.

When interpreting the results, the following statements can be made. All respondents acknowledge the potential added value of ERS-OC to HDT decarbonization. They are also all positive about engaging in a demonstration project. But, there are planning and financing concerns that have to be addressed first before stakeholder engagement can be ensured. The respondents expect governmental entities to take the lead, and account for (part of) the funding. But, they are waiting for international developments and feasibility reports before dedicating efforts to ERS-OC. Still, it is this stakeholder that is expected to take the lead and induce progression. It is up to the researchers to provide the substantiated information on ERS-OC implementation that justifies investments for the governmental entities. When clear statements and promises about the future of ERS-OC are subsequently made, freight operators and truck manufacturers will investigate the possibility to engage in ERS-OC. When these stakeholders decide to engage in ERS-OC-related projects as well, ERS-OC is likely to succeed. Trust in the future of the technology will increase among stakeholders. And then, the construction firms, road power component suppliers, and energy suppliers will engage too, adding an additional market to their portfolio without having to change their core business.

The main themes that are identified when aiming to create a demonstration project are questions like: who will take the lead? What is expected from me? Where do we start? How do we finance this? How do we start? Based on the findings of this research, the following can be recommended. Start with assigning a project leader, and create a clear vision for the future of ERS, this will create trust among stakeholders about the investments they have to make. Then, the required investments for the infrastructure should be gathered from either public or private money. When this is secured, find a suitable corridor where multiple operators drive back and forth daily and which has a high truck occupation. Bind them by making a financially attractive offer, for instance by subsidizing catenary trucks or usage of catenary infrastructure. When legal matters are in order, construction can initiate.

Further research is required on the potential environmental and financial gains when electrifying the core highway network. Here, ERS-OC should be approached as a complementary technology, thus, also integrating other zero-emission technologies into the calculations.

Crowding in trains during rush hour is known to cause discomfort. After the outbreak of COVID-19 pandemic, crowding has also been highlighted as a risk factor for catching Acute Respiratory Infections (ARIs) such as COVID-19 which has affected the demand of public transport. Several countries, including the Netherlands, have differential fare systems for peak and off-peak travel, however, the problem of overcrowding in trains is still prevalent and is expected to cause more disutility than before the pandemic. To reduce peak hour rush, change in departure time has proven to be an effective measure. In this research first a review of previous experiments related to valuation of crowding and departure time change is performed. And then an exploratory study based on a stated choice experiment is conducted to understand the extent to which people can be motivated to change departure time to avoid crowded trains during rush hours by offering them real time information on on-board crowding level and a discount on train fare. Unlike previous studies, the respondents are segregated into two groups before the start of choice experiment based on their indicated preference to schedule delay early or late. To study the change in travel behavior in the pandemic time, context of different vaccination stages is provided in the choice experiment. Background information collected in the experiment is broadly categorised as: socio-demographics, travel and work related factors, and attitude towards health and COVID-19. After the responses are analysed it is found that the coefficients obtained for main attributes are highly significant, and in line with previous research. When most of the people are vaccinated in the Netherlands, they may become less averse to on-board crowding. The research also indicates that certain groups of people can be motivated to change their departure time if real-time crowding information is provided to them. Few others can be motivated by offering incentives. However it should be noticed that to allow people to change departure time, policies such as flexible work hours and staggered commute are required in workplaces.