Dubrovnik strategy plan 

Within SOLEZ project, an Action Plan collecting a list of concrete actions that could be implemented in Dubrovnik Functional Urban Area in the next 3 to 5 years has been developed, with the scope to increase the diffusion of low carbon mobility options in the area.
Dubrovnik is a densely populated tourist center with approximately 40,000 inhabitants.
During the period outside the tourist season, the city is functional with its 40,000 inhabitants, but the population greatly increases during the summer season, leading the city to an unsustainable state. In 2017, about 2.000.000 tourists visited Dubrovnik. The current transport system does not have the capacity to meet the traffic demand generated during the summer months, when the increased number of vehicles leads to constant jams resulting in longer travel times and harmful effects of noise and emissions of polluting gases.


Starting from these considerations, from an in-depth analysis of existing traffic data and
mobility-related regulations and plans, and with the direct involvement of key stakeholders, a list of 11 priority actions have been identified, that will contribute to reduce the negative impact the transport system presently has on Dubrovnik environment.


Expected impact and benefits of the strategy

The SOLEZ Action Plan for the development of low-carbon solutions in the transport system will contribute to solving one of the key problems of the City of Dubrovnik, which is the negative impact of the transport system on the environment.


The proposed solutions will contribute to a better regulation of accesses, parking and traffic flows, and thus to reduce traffic congestions in particular in summer season. Two Pilot Actions will be implemented within the project, which will serve as a basis for assessing the feasibility of individual projects.

The establishment of the congestion charging zone will significantly reduce the number of personal vehicles in the proposed zone, and thus the CO2 emission, improving life standard of both citizens and tourists. The reorganization of the public transport system (rerouting) will create the basis for the implementation of the remaining actions (pedestrian zones, dynamic lane changes, better
connection with the Port and with the Airport, etc).

Lessons learned 

One of the requirements for SOLEZ Action Plan elaboration was a real involvement of local stakeholders. To this end, both study visits and all local peer to peer training activities contributed to the creation of trust and great business relations among all stakeholders and policy makers involved in the project.

The project made them all more collaborative, supportive and really interested in the Action Plan process. Transnational cooperation was very useful too, with twinning activities that lead to Žilina, giving some good hints on how problems we share can be solved in the future.

SMART PARKING PILOT ACTION

Collecting traffic data to design a parking regulation strategy

The pilot action is based on the introduction of the parking regulation scheme were access traffic regulations are implemented. Parking regulation scheme focuses on avoiding cruising car when finding place for parking in front of Dubrovnik historical zone.

The municipality of Dubrovnik wants to offer the more strategic management of traffic in a sustainable way

and contribute to sustainable vision (Action plan) for Dubrovnik city by:

  • persuade tourists to park their cars on the periphery of the city and to use public transport
  • reduce congestion
  • lower the CO2 emissions
  • improve quality of and fair distribution of public space

The pilot action consisted of two parts.

In the first part (customization action), was performed the general characteristics of the area, the passport of the area in relation to the infrastructure and data collection.

In the second part, we made a questionnaire by which we wanted to know if there will need to put on smart parking in Dubrovnik and if this will contribute to decrease the CO2 emissions in the City center. With this questionnaire, we found out that big number of the people who took the questionnaire would use smart parking application and by this, we decided that we should develop an app which will for sure reduce circling so many cars around the city center. In the meantime, public company Sanitat already made a public procurement for buying smart parking sensors and the development of the Smart parking application. For this reason, during the Pilot Activity, traffic data in the city have been collected manually, and this gave us exact data about the rush hours, diver’s behaviors and needs for parking places. Based on this knowledge, City of Dubrovnik is now committed to develop, together with Sanitat, a new parking and traffic regulation which will give us concrete results in terms of reduction of CO2 emissions, reduction of congestion and quality of and fair distribution of public space.

The survey has been repeated daily of parking drivers behaviors in a specific location. The survey was conducted during the pilot testing on this location: Obala pape Ivana Pavla II, Ulica Pera Bakića (Petlja 9), Ulica druge dalmatinske brigade (izlaz prema magistrali), Gornji kono (Depozit).

Thanks to monitoring and evaluating the Dubrovnik policy makers now have a data which can help in the debate with the most important stakeholders in parking strategy. Data provides objective information about traffic flow in the city center. The questionnaire from elaboration showed us that we still have space to make the prices of the parking higher. We believe that with this action we will consent people to park their cars on the periphery of the city and use our public transport to get to the city center.

Expected impacts and benefits

The pilot activity will contribute to the improvement of parking regulation scheme for Dubrovnik, which direct expected impact on Dubrovnik FUA mobility. The results from pilot action (manual counting of traffic flow) are crucial for creating and evaluating the parking scheme.

The results of the pilot action will represent a good practice, also contributing to regulate the traffic in the city center. Collected data, for example, made us understand that we still have space to improve and to increase the prices of the parking in the city enter. The City of Dubrovnik, alongside with the Sanitat, will develop new parking regulation strategies and rules based on data collected through SOLEZ pilot action, aiming at optimizing the usage of parking slot and at reducing “parasite travels” in both the city center and at FUA level. Other FUA municipalities can learn from this experience and will be invited to replicate similar approaches in their territories. 

Lessons learned and added value of transnational cooperation

During the pilot action implementation activities, mutually beneficial cooperation among separate departments of the municipal council has been successfully established. The cooperation focused, among others, on the specification of the SOLEZ action plan and on customizing the smart parking tool to detect current traffic conditions in the town center.

Lesson learned in this pilot action showed us where we need to put more of our efforts, such as traffic regulation and also parking regulation which the City of Dubrovnik is planning to do in future.

Based on all the data received by this elaboration and questionnaire we are clear in what direction we need to go to reduce congestion as well as to decrease CO2 emissions.

 The ICT smart parking tool developed during the project are described in the following deliverables available in the publication section:

Marked parking places in Dubrovnik

Marked parking places in Dubrovnik

Traffic flow counting

Traffic flow counting

CITY BUS TRANSPORT ELECTRIFICATION PILOT ACTION 

The pilot action in Dubrovnik first considered characterisation of existing (conventional/Diesel) city bus transport based on continuous, six-month, 24 hour/day GPS/GPRS telemetry tracking of representative fleet consisting of 10 buses. The main aim of the pilot action was to apply the developed software tool to virtually simulate different electric bus fleets over the recorded driving cycles, in order to determine optimal bus fleet and charging infrastructure configurations and analyse cost competitiveness of electrified city bus transport systems.

The pilot study has first involved the processing of raw driving cycle data using Data Post-Processing Module (DPPM), in order to extract a wide set of driving cycles for virtual simulation of the city bus fleet, as well as to provide comprehensive statistical analysis/characterisation of city bus transport behaviours.

Next, the virtual simulation study of different types of city bus fleets over the recorded driving cycles has been conducted in E-Bus Simulation Module (EBSM), with the main aim to analyse the extent of fuel/electricity consumption and CO2 emissions reductions when using e-buses. The considered/simulated types of city buses include: conventional (diesel-engine) vehicle (CONV), hybrid electric vehicle (HEV), plug-in hybrid electric vehicle (PHEV) and fully-electric or battery electric vehicle (BEV).

The conventional bus model has been validated with respect to recorded fuel consumption data. Furthermore, the Charging Optimisation Module (COM) along with the expert knowledge has been used to carry out repetitive fleet simulations to determine an optimal configuration of the charging system (i.e. charger locations, types, controls) for PHEV- and BEV-type city bus transport systems. Finally, the bus and charging infrastructure investment cost and energy (fuel and electricity) and other exploitation costs have been calculated in the Techno-Economic Analysis Module (TEAM), in order to calculate the total cost of ownership (TCO), compare its values for different types of buses and charging scenarios, and provide recommendations.

Expected impacts and benefits

The developed tool-supported pilot study on transport electrification has provided wide insights into the city bus transport behaviour and benefits of electrification and recommended suitable bus fleet and charging system configurations. The transport system analysis has pointed out that the city buses are resting in the depot during a relatively short period over the night (typically 3 hours), while they are dwelling at endstations for a significant time (between 15 and 25 minutes per stay). Having in mind these results and the fact that Dubrovnik does not have a city transport electric grid (from trams or trolleybuses), fast charging at end stations (based on a stationary charger equipped with pantograph) has been found to be a favourable solution. The virtual simulation results have shown that the use of HEV and PHEV city buses results in reduction of fuel consumption of up to 50% and 70%, respectively, when compared to CONV buses, while BEV buses does not consume fuel, at all. The CO2 emissions reduction equals up to 50% for HEV, 65% for PHEV, and ≈95% for BEV, provided that the electricity is produced from renewable energy sources in the PHEV and BEV cases. The charging system optimisation has shown that the optimal number of endstations equipped with fast chargers is 7, where a single bus is marginally needed in reserve in the BEV case. The TCO analysis has pointed out that the BEV fleet cannot be competitive to CONV fleet in the worst-case scenarios, while HEV fleet is competitive and PHEV fleet is marginally competitive.

Lessons learned and added value of transnational cooperation

The high share of fuel cost, coming from high utilisation of bus fleet (250 km/day/bus in average), is the reason why e-buses, which need less fuel (HEV, PHEV) or use much cheaper electricity (PHEV, BEV), can be competitive in Dubrovnik (or nearly competitive in the BEV case).

In the case of high utilisation and short resting time of buses at the depot, particularly for cities where additional space for mini-depot-like city recharging stations is expensive, one should lean towards the fast charging solution at endstations.

Since the fast charging station utilisation is low, it becomes attractive to establish e-hubs located at the endstations and powered from the bus-charger power stations (with the charging priority given to buses), which would be an additional boost to e-mobility, and which would increase utilisation of power stations and effectively reduce PHEV/BEV fleet TCO (and thus boost its competitiveness). Fast chargers do not have to be installed at all end stations if buses alternate dominantly over some of them. PHEV can be cost effective solution even for the most difficult scenarios, without special incentives or regulatory changes, and can, thus, represent an excellent transitional solution. Once the fast charging infrastructure is paid off through PHEV fleet, the next generation of fleet can be based on BEVs and it would then be cost effective and provide maximum passenger satisfaction.

The city bus transport electrification tool developed during the project are described in the following deliverables available in the publication section :

  • D.T2.3.1 - Tool for post-processing and analysis of recorded driving cycles of city bus transport
  • D.T2.3.2 - Computer simulation model of conventional and e-bus fleets
  • D.T2.3.3 - Optimization tool for e-bus fleet charging management
  • D.T2.3.4 - Computer model for techno-economic analysis of city bus electrification cost