Posts

Jevons Paradox: Efficiency That Increases, Not Saves, Energy Use

An introduction to the Jevons Paradox William Stanley Jevons published The Coal Question in 1865, warning that improving the efficiency of coal‑powered steam engines might not reduce coal consumption; it could increase it because cheaper power would spread across more industries and households.1 2 His observation—that making a resource use more efficient can lead to more consumption overall, not less—has become known as the Jevons Paradox, often discussed today under the broader idea of “rebound effects.”3 2

Friday, April 10, 2026 | 9 minutes Read

Real fuel prices in Germany as of 2025

The Story Today I came across several plots showing the development of real fuel prices in Germany since 1970, generated with the help of AI. At first glance, some of the price spikes appeared unusually high and did not seem fully consistent with a long-term economic perspective. To verify this, I decided to reconstruct inflation-adjusted fuel prices myself. For this purpose, I used two data sources: the annual inflation rates provided by Destatis and historical fuel price data from ADAC dating back to 1950. By combining these datasets, I recalculated all historical fuel prices to a common reference level—namely the price level at the end of 2025.

Tuesday, April 7, 2026 | 2 minutes Read

Cost Comparison: Public Transport, Ecomobility, and Car Use in Germany

Text is Work-In-Progress Introduction Public debate about mobility often focuses on ticket prices, fuel costs, or whether “owning a car pays off.” This perspective is too narrow. Mobility is not just an individual consumption choice but also a question of infrastructure, spatial structure, social participation, and societal financing. Anyone seriously examining the cost comparison between cars and public transport must consider both direct household expenditures and broader macroeconomic consequences.1 2 In Germany, mobility is spatially very unevenly organized. In densely urban areas, many trips can be completed using the Umweltverbund (ecomobility; the sustainable bundle of public transport, cycling, and walking). In rural areas, however, cars are often not merely a convenience option but a prerequisite for everyday mobility.3 4 This creates a fundamental difference: while cities primarily ask how mobility can be organized affordably and with low emissions, rural areas frequently grapple with ensuring mobility reliability in the first place.4 5

Tuesday, March 31, 2026 | 10 minutes Read

Academic Publications

Peer-Reviewed Publications (Referenzierte Publikationen) 2025 Analysis and stress-test of the spatial accessibility to German radiation oncology centers Analyse und Stresstest der räumlichen Erreichbarkeit deutscher Strahlentherapiezentren Straube, C.; Medenwald, D.; Mayregger, P.; Holthaus, T. Strahlentherapie und Onkologie DOI: 10.1007/s00066-025-02435-7 2024 Locations of LTL logistics service providers as urban consolidation centers – the Düsseldorf case and its transferability Standorte von Stückgutlogistikdienstleistern als urbane Konsolidierungszentren – Fallstudie Düsseldorf und Übertragbarkeit Thiemermann, A.; Holthaus, T.; Mayregger, P.; Leerkamp, B. Transportation Planning and Technology, 1–26 DOI: 10.1080/03081060.2024.2420272 2023 Example application of the guidelines for integrated network design in freight transport Beispielhafte Anwendung der Richtlinien für die integrierte Netzgestaltung für den Güterverkehr Thiemermann, A.; Holthaus, T. Straßenverkehrstechnik, 01/2023, Bonn DOI: 10.53184/SVT1-2023-1 Conference Proceedings (Konferenzberichte) Author links open overlay panelChristopher Caratiola a, Florian Ertz a, Florian Groß b, Tim Holthaus b, Bert Leerkamp b, Ralf Münnich a

Monday, March 23, 2026 | 6 minutes Read

Committees & Memberships

Road and Transportation Research Association (FGSV) AK 1.2.10 – Big Data in Transport Planning (Big Data in der Verkehrsplanung) Website of AK 1.2.10 Member since 2022 AK 1.1.3 – Accessibility Planning (Erreichbarkeitsplanung) Website of AK 1.1.3 Member since 2021 AA 1.3 – Network Design (Netzgestaltung) Website of AA 1.3 Member since 2014 AA 1.6 – Public Transport (Öffentlicher Verkehr) Website of AA 1.6 Member since 2022 AK 1.6.12 – Urban Cable Cars (Urbane Seilbahnen) Website of AK 1.6.12 Leader since 2022

Monday, March 23, 2026 | 1 minute Read

Medial Publications/Work

2026 Science Media Center (2026) Neue Mindestfallzahlen für Knie-OP – Auswirkungen auf die Erreichbarkeit von Kliniken: Calculation of travel times based on the 100 m grid (GeoGrid) of the 2022 Census. 📅 24.04.2026 In the coming years, the number of hospitals performing orthopedic knee surgeries is expected to decrease due to new minimum case volume regulations. This consolidation is likely to result in longer travel times to the remaining facilities.

Monday, March 23, 2026 | 4 minutes Read

Research Dissemination

Research Presentations 2024 Erreichbarkeit von Krankenhäusern Accessibility of hospitals SciCar 2024 – Joint workshop with Lars Koppers (SMC), Ulrich Lang (SWR) and Sven Lautenbach (HeiGIT & Heidelberg University) Dortmund, Germany · 27.09.2024 2023 Methodik und Ergebnisse der Multi-Source-Analysen – Teil: Erreichbarkeit und Pendeln Methodology and results of multi-source analyses – focus on accessibility and commuting Final conference of the project VerBindungen Berlin, Germany · 03.11.2023 VerBindungen: Pendlergewichtete Reisezeiten im mIV und ÖPV VerBindungen: commuter-weighted travel times in private and public transport Statistische Woche 2023 Dortmund, Germany · 11.09.2023

Monday, March 23, 2026 | 2 minutes Read

Teaching & Supervision

Courses Bergische Universität Wuppertal Computersimulationen des Fußverkehrs, ÖPNV- und Straßenverkehrs (Teil 5.18-a) Computer Simulation of Pedestrian, Public Transport and Road Traffic (Part 5.18-a) Period: 04/2022 – 04/2025 Role: Primary Instructor Responsibilities: Full responsibility for course design, teaching, and assessment Focus: Public transport and road traffic Grundlagen der Verkehrsmodellierung und Systemtheorie Fundamentals of Transport Modelling and Systems Theory Period: 10/2019 – 04/2023 Role: Co-Instructor Responsibilities: Co-responsible for course design, teaching, and examinations Netzgestaltung im Güterverkehr Network Design in Freight Transport

Monday, March 23, 2026 | 5 minutes Read

Influence of the Planned Hospital Reform on Accessibility

Background Last year, Julius Tröger approached me and informed me about the ongoing discussion regarding the hospital reform in Germany. We already knew each other from a joint project for ZeitOnline, where we calculated the accessibility of vaccination centers for various scenarios.1 Yes, 2021 was a crazy year. Now… since the workflow for examining hospital accessibility is very similar, if not identical, it quickly became clear that we would collaborate again this time.

Saturday, May 4, 2024 | 5 minutes Read

Function to determine German holidays in PostgreSQL-12

Background Big data must be enriched with other information so that observations and behavior can be analyzed exaltly. This also includes holidays because they have a strong influence on people’s behavior. So that the holidays do not have to be researched manually for each year, it is advisable to convert the logic behind the (German) holidays into a plpgsql function (see below – tested with PostgreSQL 12). PSQL-Function Holidays that are not defined by an exact date are dependent on Easter. The lower function returns the date for Easter Sunday for the desired year.

Tuesday, October 20, 2020 | 3 minutes Read

Cycling in the Bergische Städtedreieck – SimRa

Project Description The project Sicherheit im Radverkehr (SimRa; engl: Safety in Cycling) by TU Berlin is funded by the Citizen Science initiative. Its goal is to identify main bicycle traffic flows and the hazardous situations that arise during these movements. For this purpose, the Scalable Software Systems developed a tracking app that records GPS data and acceleration sensor data anonymously. In addition to general information about the cyclist (age, gender, experience, …), users are asked after each ride whether a hazardous situation occurred and which type of bicycle was used. The hazard can then be described in more detail (involved road users, type of situation, etc.).

Saturday, February 1, 2020 | 3 minutes Read

Comparison of Timetable Versions Using Travel Time Isochrones

Isochrones derived from real timetable data enable a direct comparison between different timetable versions. This method plays a key role in identifying deficits within transport networks and irregularities in service frequency. Beyond timetable optimization, visualizing isochrones can also serve as an effective communication tool for public information. By presenting timetable improvements in a simple and easily understandable format, these visualizations foster greater public acceptance of timetable changes. Case Study: Wuppertal Following the reconstruction of the Wuppertal main station and its surrounding area, the new bus terminal—located directly adjacent to the station and accessible from platform one—is expected to be completed within this year. According to timetable data recorded in the EFA system, the terminal is scheduled to open to bus traffic on Sunday, October 28, 2018.

Wednesday, August 29, 2018 | 2 minutes Read