NexSys researchers in the news: Dublin commuters prefer walking over bicycles and e-scooters in conjunction with public transport

Commuters in County Dublin prefer walking over bikes and e-scooters as a means of getting to and from work before or after a public transport journey, according to a study co-authored by NexSys researchers recently published in the inaugural issue of the Journal of Cycling and Micromobility Research.

Micromobility – a term used to describe small, light electric vehicles such as bikes and e-scooters – is often promoted as a low-carbon alternative that can help people move away from using private cars and taxis since it can improve connectivity of existing public transport networks. However, there has been little research to date on micromobility as a travel choice in the first mile (also known as access trip) and last mile (egress trip) of a commute.

The study authors, through an online survey with 450 responses, investigated how commuters in County Dublin prefer to travel in the first- and last-mile of public transport trips. They also examined the influence of characteristics such as gender and age on people’s choice of micromobility, including shared bicycles and e-scooters, compared to walking. 

In the survey, residents of County Dublin were asked about the mode of transport they would choose in hypothetical commute scenarios, including in the first mile of a commute with private bicycles and e-scooters, and in the last mile with shared bicycles and e-scooters. 

Using statistical models to analyse the responses, the researchers found that walking was the preferred option for commuting for most respondents, even when other options were available and provided significant reductions in travel time.

“This was one of the more surprising outcomes of the survey,” said lead author Giulia Oeschger, PhD candidate at UCD’s School of Civil Engineering. “I was expecting a lot of people to be more concerned with travel time, since cycling and e-scooter-use drastically reduced travel time in the experiment, but despite this a lot of people still deliberately chose the walking option which is always the longest. The population of Dublin seems to really love walking and our survey shows they do it for enjoyment or for exercise. This seems to be a characteristic of the city of Dublin,” she said. However, how the available infrastructure and the perceived safety of cycling and e-scooter use on the streets of Dublin influence the results has not been looked at in this particular study, and is something that the authors feel should be investigated further.

Giulia Oeschger headshot Paraic Carroll 

Left: Lead author Giulia Oeschger; Right: Dr Páraic Carroll, Assistant Professor in UCD’s School of Civil Engineering and lead of the transport strand at NexSys at UCD

The authors also found important differences in transport preference in relation to gender and age. Young (less than 35 years old) and male respondents are significantly more likely to choose e-scooters and bicycles, while older and female respondents are significantly more likely to choose walking, even if other options were significantly faster. This is consistent with previous studies which also found that e-scooter users are predominantly young and male, the authors note in the paper. 

Dr Páraic Carroll, Assistant Professor in Transport Engineering at UCD’s School of Civil Engineering and one of the authors of the study, states that “while the results of this study highlight that walking was the preferred choice for first and last mile segments of a journey, it also accounts for the existing limited ability to combine active modes or micromobility trips with public transport in Dublin and across the country due to, in some cases, modes not being well integrated with one another and the limitations in bringing private bikes or scooters onto public transport vehicles. However, the walkability of our access trips to and from public transport stops/stations is a key component influencing the attractiveness of public transport services.” 

Availability of secure parking was an important consideration when it comes to choosing transport modes, the authors found. 

The researchers argue that these results confirm that younger generations have a growing interest in micromobility, but regulations and adequate infrastructure are needed to promote equitable access to these modes of transport, with a particular focus on attracting users away from more carbon-intensive transport such as private cars and ride-hailing trips.

The paper co-authors are:

– Giulia Oeschger, PhD candidate at UCD’s School of Civil Engineering;

– Dr Páraic Carroll, Assistant Professor in UCD’s School of Civil Engineering and lead of the transport strand at NexSys at UCD;

– Professor Brian Caulfield, Professor in Transportation in the Department of Civil, Structural and Environmental Engineering, Trinity College Dublin (TCD) and funded investigator with NexSys. Giulia Oeschger and Dr Páraic Carroll are also part of the UCD Transport Research Hub (TREAH), which Dr Carroll leads. 


This research is funded by University College Dublin, School of Civil Engineering, under the MicroActive Dublin research project. 


About NexSys and its transport strand

Next Generation Energy Systems (NexSys) is an all-island, multidisciplinary energy research programme. NexSys is hosted by the UCD Energy Institute in partnership with eight other leading research institutions. 46 leading academics work in partnership with industry to tackle the challenges of energy decarbonisation, developing evidence-based pathways for a net zero energy system. 

The NexSys transport research strand is investigating the critical infrastructure, behavioural and policy challenges of transitioning to decarbonised multi-modal transport and renewable energy use in a fair way, and identifying tangible evidence-based solutions via engagement and collaboration of key stakeholders tasked with implementing them.

News coverage:

The Independent: Walking wins out over scooters and bikes for ‘last mile’ of city commutes

UCD News: Public transport commuters prefer pounding the pavement over bicycles and e-scooters – University College Dublin (


Researcher spotlight: Maryam Pourmahdi

NexSys PhD researcher Maryam Pourmahdi, based in UCD’s School of Electrical and Electronic Engineering, was recently awarded the Best Paper Award at the Universities Power Engineering Conference (UPEC) in TU Dublin. 

We catch up with Maryam below.

Maryam Pourmahdi headshot

What is your NexSys research about and what are you working on at the moment?

My research focuses on creating better and more efficient devices called “rectifiers” that convert alternating current (AC) from the grid to direct current (DC) for use in various applications like electric vehicle charging, power supplies, and hydrogen production. I’m currently working on a design that not only improves energy efficiency but also reduces electromagnetic interference noise, making it safer and more grid friendly. The title of my NexSys project is ‘Advanced Active rectifiers for grid connected applications.’

How did you become interested in this research field?

I was initially intrigued by the challenges of modern power systems and the importance of energy efficiency. With the growing demand for DC power in various applications, the role of rectifiers becomes critical. This led me to explore how these devices could be designed to be more efficient, reliable, and compatible with the power grid.

What is one interesting fact about your research area people may not know about?

My research offers ‘grid-friendly’ rectifiers that not only reduce electrical noise but also maintain stable interactions with the electrical grid. This is critical for preventing disruptions and failures. Additionally, my work has applications in electrolysers for green hydrogen production, making them more efficient and compact.

What is the wider relevance of your research to the energy transition?

The efficiency and reliability of rectifiers are paramount, especially when applied to electrolysers—devices pivotal to the production of green hydrogen, an emerging clean energy source. As the world shifts towards cleaner energy solutions, my research on advanced rectifiers can significantly enhance the efficiency of hydrogen production systems. This translates to reduced energy waste, lower greenhouse gas emissions, and more affordable green hydrogen, potentially accelerating policy shifts towards this sustainable energy option.

You recently won a Best Paper Award at the Universities Power Engineering Conference in TU Dublin. Congratulations! What was the paper about? 

The paper title was “Dual-Cuk High Step-up Bridgeless PFC Converters with Continuous Input and Output Currents”. This paper proposes two novel types of dual-Cuk bridgeless rectifiers for voltage conversion in power systems. These grid-friendly rectifiers overcome the limitations of conventional boost rectifiers and offer several significant advantages including high reliability, low voltage stress across the semiconductors, continuous input and output current, and high step-up voltage operation capability.

What is something people may find surprising about you?

Outside the lab, I have a passion for painting and portraiture, where I find a different kind of creative expression compared to my scientific work. I also enjoy playing the guitar, which serves as a melodic break from the analytical world. Additionally, I love feeding birds; it’s a simple act that brings me immense joy and a sense of connection to nature.

NexSys researchers take part in EirGrid research forum

NexSys researchers were delighted to take part in the EirGrid Research Forum which took place on 29 August in Dublin. 

EirGrid is one of NexSys’ industry co-funding partners, which include Ireland’s leading energy providers. 

Three NexSys researchers shared their current research and findings on topics ranging from inverters and the grid, gender and the energy transition, and the role of data centres in future energy systems.

Associate Professor Paula Carroll (pictured below), a NexSys funded investigator who is based in UCD’s School of Business, gave a presentation entitled Gender Mainstreaming in the European Union Energy Transition. She discussed the results of her recent literature review on the Energy/Gender nexus. 

Paula Carroll presenting a talk at EirGrid Research Forum

Associate Professor Terence O’Donnell (pictured below), NexSys Co-Lead of the Energy Systems Strand and based in UCD’s School of Electrical and Electronic Engineering, gave a talk entitled Harmonic resonances associated with grid connected inverters. As part of his presentation, he covered results of recent published research co-authored with Dr Ramy Ali.  


Terence O'Donnell presenting at EirGrid Research Forum



Alireza Etemad (pictured below), NexSys PhD student based in UCD’s School of Mechanical and Materials Engineering, presented his research on The Role of Data Centres as Prosumers in Future Energy Systems. Alireza, who is working with Associate Professor James O’Donnell as part of his PhD, is also a Senior Energy Policy Researcher at SEAI’s Decarbonised Heat Group.

Alireza Etemad presenting at the EirGrid Research Forum

 About NexSys

Next Generation Energy Systems (NexSys) is an all-island multidisciplinary research programme, involving nine different research institutions, alongside industry partners from across the energy sector. The programme’s key aims include tackling the challenges of energy decarbonisation, and developing evidence-based pathways for a just, net-zero energy system.

NexSys is financially supported by Science Foundation Ireland under the SFI Strategic Partnership Programme (Grant Number 21/SPP/3756), industry co-funding partners, and a philanthropic donation by Mr David O’Reilly. NexSys’ nine industry co-funding partners are: EirGrid, ESB Group, Davy, Atlantic Hub, CIE, RWE, EPRI, Gas Networks Ireland and SSE Airtricity. In addition, NexSys has an extensive network of collaborating partners, which will be essential in providing an evidence base for policy and delivery of services.

Blog post: A week at the EURO PhD Summer School

By Clíodhna Ní Shé

Clíodhna Ní Shé is a PhD student in the Transport strand of NexSys, based in the School of Business at University College Dublin. Clíodhna’s research focuses on optimisation algorithms, with a focus on electric vehicle routing problems and last mile logistics. A vehicle routing problem is a combinatorial optimisation problem which aims to find the optimal set of routes for a fleet of vehicles to traverse in order to deliver to a given set of customers. Last mile logistics concerns the last stretch of the supply chain, from the last distribution centre to the recipient’s preferred destination point.

In her spare time Clíodhna plays Gaelic Football for Carlow. From 25 to 29 June, she attended the EURO PhD summer school on sustainable supply chains in Hagen, Germany, and writes about her experience below.

Clíodhna Ní Shé


I set out from Dublin to Dusseldorf airport, where I would have to navigate two connecting trains and a bus to get me to my accommodation in Hagen, a city in the state of North Rhine-Westphalia. I was due to arrive at my accommodation around 12 noon, but due to numerous delays and miscommunications in Deutsche Bahn, I only checked in at 5 o’clock.  Hungry from the arduous trip, I was overjoyed to be greeted by a generous buffet of Lebanese food as I entered the Sunday evening get together. Following mildly awkward introductions, we enjoyed the delicious food in the heat, along with bottles of beer, cola and ‘radler’, a traditional German drink.


Bright and early in the morning, summer school delegates walked from the accommodation to the FernUniversitat, Germany’s only state distance learning university. With over 73,500 students, it is also the largest university in Germany. Throughout the busy week we were treated to lectures and tutorials on designing sustainable supply chains, benchmarking supply chains, and the circular economy. Monday’s lecture and tutorial concentrated on assessing sustainability in supply chains. First, I learned about the relevance and challenges of life cycle sustainability assessments. Following this, I learned about the steps of a life cycle assessment (LCA) and how to interpret the results. I was then introduced to social LCA and how to assess the environmental and social impacts, an interesting aspect of LCA that I hadn’t encountered before. In the afternoons, we were split into groups to work on various case studies. The case studies were introduced to us by representatives from industry partners Volkswagen and Holocene.


As the week went on, lecture focused on the planning of sustainable supply chains and the problems that arise when doing this planning. As part of learning about benchmarking sustainable supply chains, we were also introduced to data envelopment analysis.

A highlight of the trip was the field trip on Tuesday evening that we took to the Koepchenwerk pumped storage power plant, which has been shut down since 1994. We were treated to a very informative tour of the scenic plant. We then walked to an Italian restaurant where we had a lovely meal together.


Thursday’s lecture on the circular economy was particularly interesting as we discussed many possible circular supply chains and the possible advantages and disadvantages of them, as well as their realistic viability.

On this final day of the summer school, we presented our case study presentations to our peers and to the relevant stakeholders.

Returning home

There is no doubt that throughout the week we gained valuable knowledge from experts that guided us through cutting edge quantitative research in this vital field. However, the most valuable information was gained from my peers with whom I collaborated and had the opportunity to share stories and connect with.

Summer School Participants
Summer School Participants

Pictured above: Summer school participants

Engaging Energy Citizens on the value of Science, Technology, Engineering & Maths

NexSys completes 6-weeks of STEM engagement 

NexSys researchers and team members have just completed a six-week programme of public engagement, funded by SFI’s Discover Programme. 

The programme, called Little Big Questions, engaged primary school children from the Travelling community with science, technology, engineering and mathematics (STEM). The children, aged 8-12, visited UCD and took part in experiments and activities ranging from pH testing, eye colour experiments, space and rocket science, energy, motors and circuits, to the research process itself.

The activities were coordinated by staff from NexSys, Insight, UCD Discovery Institute, with collaboration allowing for a diversity of STEM activities for primary school children.

NexSys researchers were involved in presentations to the primary school visitors as part of NexSys’s EPE programme.  

“In any classroom, you will find a wide range of interests. A varied programme of activities that speaks to the diversity of things to study and careers to pursue from STEM translates into more opportunities to connect with young people and their individual interests,” said Lorna Byrne, NexSys Education & Public Engagement Officer.

Associate Professor Julie Byrne, EPE Champion and Finance Theme Lead for NexSys, said: “Young learners who visit UCD for these programmes get to hear from early and advanced career researchers. There is a great sense of connection in the room as they learn about why these researchers are interested in what they are, and who they are as people. 

“Lorna facilitates an environment that enables PhD students and faculty to be accessible role models. Those participating in such events receive powerful messages along with some very cool learning experiences in our outreach labs. As researchers, we all learn the difference between ‘dumbing down’ and ‘simplifying’ our messages about the power of science in providing solutions to real-world problems,” said Julie.

Professor Andrew Keane, Director of NexSys and the UCD Energy Institute, said: “The energy transition affects everyone, and perhaps particularly the youngest generations. By engaging younger generations on the role of energy, we hope to empower the next generation of energy citizens to make evidence-based decisions, and inspire them to become curious about research in general.”

Children, teachers and organisers on the final day of the programme.

Lorna was recently awarded a UCD College of Engineering & Architecture Teaching & Learning Award. The award, which was made in November 2022, recognised Lorna’s ‘exceptional contribution to learning’ through workshops conducted in 2021/2022.

The programme ran with schools from across Dublin and engaged 8-12 year olds in Science, Technology, Engineering and Maths (STEM).  

About the NexSys EPE programme

The EPE vision for the NexSys programme is to define the pathways to a net zero energy system by 2040 with the Energy Citizen at the core. This means creating opportunities to engage with a wide range of stakeholders and decision makers across relevant sectors. 

NexSys’ EPE activities range from educating school children on the role of energy, inspiring generations of curious researchers, as well as engaging with policy makers and industry stakeholders in supporting evidence-based decision making.

Nexsys researchers explore the just transition

NexSys researchers Dr Aparajita Banerjee and Assoc. Prof Geertje Schuitema, who lead the Just Transition Research Group in University College Dublin hosted a half-day conference on just transition in Ireland on 7 June. Dr Banerjee and Assoc. Prof. Geertje Schuitema are both based in University College Dublin’s School of Business and part of the NexSys research partnership.

Dr Aparajita Banerjee

Dr Aparajita Banerjee opening the conference


The event, also organised by Oscar Mooney, Project Coordinator for the Just Transition Research Group and research assistant at UCD, took place in UCD’s Smurfit Business School Campus and online. It was sponsored by the UCD Earth Institute SPSM Funding Mechanism.




Transitioning to a low-carbon economy requires transformative changes in technology, society, human behaviour, and institutional practices.


The conference facilitated a cross-disciplinary dialogue to encourage integrated and interdisciplinary knowledge and understanding of how a Just Transition to a low-carbon future can be achieved.


Here are some of the questions that were explored:


●How can research on Just Transition contribute to the decarbonisation of our socio-economic systems?

●How can we produce knowledge that can ensure social justice is not compromised during the transition process?

● How can integrated and interdisciplinary research contribute to solving complex societal problems?


Assoc. Prof Schuitema said: “The just transition is a so-called wicked problem, which means it’s very difficult to solve due to its complex, multi-layered and interconnected nature. This is why we need a discussion that includes different perspectives and angles. The fact we heard so many perspectives today is what made this conference really inspiring.”


In rounding up the conference, she also noted some of the common themes that emerged from the discussion, including:

  • The need for radical change when it comes to achieving a just transition
  • The just transition is an opportunity to reduce existing inequalities
  • Solutions must involve and include the communities, workers, farmers and all those impacted on the ground
  • The need for institutional change, with well designed bottom-up and top-down approaches.
  • The recognition that technological solutions are needed, but also have societal and political implications
  • Researchers can play an active role in driving projects, talk to industry and policy makers, and empower communities


A recent publication by NexSys researchers


Policymakers need to include spatial differences to ensure a just transition: a case study from the Irish midlands


A month before the conference, a new paper by Dr Aparajita Banerjee and Associate Professor Geertje Schuitema was published. The paper argued that, in order for a just transition to take place, policymakers need to take into account spatial differences such as different geographies, access to natural resources, and availability and accessibility of socially-valuable resources such as education, healthcare and transport. Spatial differences can exacerbate inequalities, especially when it comes to rural spaces such as in the Irish midlands, the researchers wrote in the paper.


As the world transitions away from fossil fuels, many regions, and especially rural areas, face both economic and non economic losses (including job losses). Policies that help ensure a just transition for impacted communities, people, and regions are usually referred to as ‘just transition’ policies.


The authors examined a case study from the Irish midlands, where industrial peat extraction for electricity production was discontinued after the closure of associated power plants in 2020.


Under the European Union Just Transition Programme, funding of 169 million euro has been allocated to the region until 2030, as well as 22 million euro put in place by the Irish government, to help communities in the midlands impacted by the closures.


Based on documentary evidence and 30 in-person interviews with community members living in Co. Offaly and Co. Longford, close to the power stations and peatlands where extraction was taking place before closure of the industry, community members felt little was done to prepare the region for a just transition, despite evident decline of the industry for many years, the researchers report.


“Preparing a region to be able to provide alternative livelihood options is critical to absorb the shock of the sudden job cuts. These alternative livelihoods should align with what people in the region want so that the characteristics of the space are maintained,” said Dr Aparajita Banerjee.


Locals felt frustrated and angry, and perceived they were not included in the just transition process. Another theme that emerged was a sense of loss which included tangible job losses and intangible losses due to the connection between the peat industry and the local social and cultural fabric.


Based on these findings, the researchers argued that spatial differences, incorporated in the notion of spatial justice, can enhance social justice or injustice, and thus must be accounted for in policy around the just transition. A lack of alternative jobs and industries in the region, due to prolonged underinvestment, was one issue that emerged from the interviews. Rural development must become part of a long-term just transition policy plan, say the authors in the paper.


The research, which was supported by Science Foundation Ireland (SFI), is published in the journal Environment and Planning C: Politics and Space, and is free to read.



For more information:


Just Transition: Embedding social justice in low-carbon futures – UCD Just Transition Research Group


Link to paper