Nach oben pdf Linking the Power and Transport Sectors—Part 2: Modelling a Sector Coupling Scenario for Germany

Linking the Power and Transport Sectors—Part 2: Modelling a Sector Coupling Scenario for Germany

Linking the Power and Transport Sectors—Part 2: Modelling a Sector Coupling Scenario for Germany

The grid itself was recreated according to the German grid development plant [32], which includes transmission lines at 380 and 220 kV, in addition to high voltage direct current transmission (Figure 6b). For the purposes of this study, all lines are assumed to operate with a loss of 0.055%/km [31]. Furthermore, the type and location of all power plants is based on information from the German Bundesnetzagentur (Figure 6a) [46], which provides a list of all power plants with a nominal capacity above 10 MW and includes, amongst other details, the federal state in which the plant was built, as well as its capacity, fuel type and year of first operation [31,47]. With the current plan of phasing out nuclear plants, in addition to reducing overall GHG emissions, the German energy mix will change rapidly in the coming years. To reflect this, the model allows for the selection of a subset of the power plants that are currently in operation, thus creating a conventional resource capacity scenario. For example, in accordance with German policy, all nuclear plants have been filtered out of the final analyses. In order to calculate a marginal cost for each power plant, an in-house analysis was performed to estimate the operating efficiency as a function of plant type, age and fuel cost, in addition to applying an optional carbon tax for all plants. Finally, to account for the import and export of energy to surrounding countries, the model also incorporates historic transfer values from a number of different sources [48–55]. Historical values were used in this case in order to avoid an overly complex scenario-space in which the residual load would need to be determined for all surrounding countries. Nevertheless, this approach was shown to provide reliable results [19].
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Linking the Power and Transport Sectors—Part 2: Modelling a Sector Coupling Scenario for Germany

Linking the Power and Transport Sectors—Part 2: Modelling a Sector Coupling Scenario for Germany

Abstract: “Linking the power and transport sectorsPart 1” describes the general principle of “sector coupling” (SC), develops a working definition intended of the concept to be of utility to the international scientific community, contains a literature review that provides an overview of relevant scientific papers on this topic and conducts a rudimentary analysis of the linking of the power and transport sectors on a worldwide, EU and German level. The aim of this follow-on paper is to outline an approach to the modelling of SC. Therefore, a study of Germany as a case study was conducted. This study assumes a high share of renewable energy sources (RES) contributing to the grid and significant proportion of fuel cell vehicles (FCVs) in the year 2050, along with a dedicated hydrogen pipeline grid to meet hydrogen demand. To construct a model of this nature, the model environment “METIS” (models for energy transformation and integration systems) we developed will be described in more detail in this paper. Within this framework, a detailed model of the power and transport sector in Germany will be presented in this paper and the rationale behind its assumptions described. Furthermore, an intensive result analysis for the power surplus, utilization of electrolysis, hydrogen pipeline and economic considerations has been conducted to show the potential outcomes of modelling SC. It is hoped that this will serve as a basis for researchers to apply this framework in future to models and analysis with an international focus.
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Linking the Power and Transport Sectors—Part 1: The Principle of Sector Coupling

Linking the Power and Transport Sectors—Part 1: The Principle of Sector Coupling

The Fraunhofer ISE study [ 73 ], which is represented in Figure 4 in the second category with three different scenarios, points out the possibility of realizing all of Germany’s power and heat demand via renewable energies. In the study, electricity storage is taken into account by including pumped hydro storage and batteries, while thermal energy storage is considered through the inclusion of water as a storage medium. The scenarios refer to different degrees of refurbishment for buildings (heat demands of 64.9%, 50% and 40% in reference to the 2010 values for REMax, Medium and SanMax, respectively). A P2G path is integrated as follows: first, hydrogen that was produced by electrolysis during periods of excess electricity generation is transformed into methane; this methane is then stored in already existing caverns for natural gas; finally, during times of positive residual load, the methane is used to produce electricity and heat. Not modeled are the transport sector and fuel-based industry processes. However, the study states that if transport was included (by assuming 50% BEVs and 50% FCVs), an additional yearly electricity demand of 290 TWh would be required.
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Linking the Power and Transport Sectors—Part 1: The Principle of Sector Coupling

Linking the Power and Transport Sectors—Part 1: The Principle of Sector Coupling

In 2013, the global electricity production totaled about 79,656 PJ. With regard to the contributing fuels, hard coal and lignite accounted for the biggest share, at 39%, followed by natural gas, at 22%. The contribution of RESs, such as hydro power, wind energy and PVs, amounted to 20%, and 22% if biomass was included [94]. Taking into consideration the expansion of RESs, 2015 was remarkable not only because of the COP21 agreement, but also because a new record of RES growth in installed capacities was hit, despite many countervailing factors. Overall, global non-hydro capacities totaled 785 GW, which amounted to 7.6% of the total electricity production in 2015. If hydro power was included, this number grew to 23.7% [95]. These numbers are expected to grow rapidly, especially as the technology for integrating RESs into the system further develops. Currently, the world adds more renewable power capacity than net capacity from all the fossil fuels combined, i.e., 134 GW in RESs excluding large hydro, 22 GW in large hydro, 15 GW in coal-fired plants, and 40 GW in gas-fired plants. Overall, USD $286 billion were invested in RESs, in contrast to $130 billion for fossil fuel generation technologies [96].
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Linking international trade and transport - what are the determining factors?

Linking international trade and transport - what are the determining factors?

1 1. Introduction Transport on the European road network is growing steadily despite the political awareness of the negative consequences of this growth and the willingness to implement measures to deal with these problems. Capacity is becoming scarcer and scarcer, and congestion can often be observed even for interurban transport in Central Europe. Other externalities are also an in- creasing negative consequence of transport that must be dealt with. To deal with these prob- lems it is necessary to have an idea of the reasons for the increasing transport. This paper aims at finding indications of which elements that play the most important role for the growth in in- ternational freight transport.
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New developments and validations for the 3D sediment transport modelling within the Telemac Modelling System

New developments and validations for the 3D sediment transport modelling within the Telemac Modelling System

In the 2D model, the depth-averaged suspended sediment concentration is calculated by solving an advection-diffusion equation. In this 2D transport equation, a correction factor can be applied to the advection term in order to account for the non-uniform vertical distribution of flow velocity and concentration over the depth [7]. In the 3D model, the flow field is computed by solving the continuity equation and the Reynolds-averaged Navier-Stokes equations. The Reynolds stress tensor is modelled by suitable turbulence closure relationships. The suspended sediment load is then calculated by solving the full 3D convection-diffusion equation for the suspended sediment concentration distribution. As pointed by Begnudelli et al. [2], sediment transport rate predictions can be highly sensitive to the choice of the near-bed concentration and reference level. Therefore, a methodology is proposed to avoid infinite concentrations at the bed level, while conservation properties are upholding.
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MOREMix - Power sector optimization for Morocco

MOREMix - Power sector optimization for Morocco

Integration of variable renewable energies (VRE, wind power and photovoltaics) has a significant impact on the performance of conventional thermal power plants (e.g. number of start-ups, part-load operation, etc.) and the need for different kind of adequacy and system operation reserve capacities in the electric system which should be considered already within capacity expansion planning. Typically, capacity expansion models using load duration curves (LDC) for capacity expansion of hydro-thermal dominated power systems. This approach has the advantage of low computational effort and was highly suitable in times where VRE technologies have been no economical feasible investment options or no climate mitigation strategies were of interest. Using s LDCs for capacity expansion planning leads to the loss of load chronology and information about the availability of renewable energy resources over time whereby the impact of VRE on the power system cannot be considered within capacity expansion planning. Utilizing LDCs for capacity expansion optimization has two major drawbacks:
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Labour relations in comparative perspective: Special focus on the SME sector (part 2)

Labour relations in comparative perspective: Special focus on the SME sector (part 2)

initiated by employees/trade unions; e.g. as in Hungary, Germany, Poland and Spain. In spite the fact that the minimum size in some countries do not exist or in the majority of the countries involved in the Leonardo Project, the threshold is 5, 50 or 100 employees – these workforce-sizes are covering the small and medium- sized firms, the works councils are important participatory forum for employees in the large firms (LSE). Even the law provides basis for works councils in such countries as Germany, France, Hungary and Spain, in the SMEs only tiny minority of firms establishes works councils. “In Germany, for example, the law provides statutory rights in firms with five or more employees. The establishment of a works council is not mandatory and according to survey figures from 2002, works councils cover just 11 % of all firms and 50 % of all employees within the law’s scope. Coverage is related to the size and the age of the firm, with smaller and newer firms much less likely to have established a works council….In France, the Ministry of Labour estimates that of small firms (10-19 employees) less than 20 % have a form of workplace representation for employees. This percentage increases to 56 % for firms with 20-49 employees and to 90 % in firms with more than 50 employees.” (Industrial Relations in Europe 2004:22.) The situation is rather similar in Hungary. However, the relation between the size of the firms and works councils call attention to another vital issue. The rate of the presence of the works councils has strong relations with the trade union presence in the firms surveyed. According to the date of a statistically representative survey carried out in 2002 in Hungary, the share of works councils, trade unions and collective agreements are indicating the similar trend: their share is increasing with the size of the firms. (See Table 15! )
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The European power sector in ...:

The European power sector in ...:

step change in electrification of transport and heat is yet to come. Electric car sales were up 34% in 2018 resulting in 2.4% of new car sales being electric. The overall weather impact on electricity use in 2018 was small. 2018 was a very warm year across the whole of Europe and 0.4 degrees warmer than 2017 (see Figure 2-2). February and March were the only two cold months, when the so-called “Beast from the East” swept windy cold air across Europe. The other ten months in 2018 were significantly above normal temperatures. Overall, the winter months were warm so the reduced heating demand offset the additional air conditioning demand in the hot summer months. The trend in electricity consumption in 2018 fol- lowed a similar pattern to previous years – rising in eastern European countries, and stagnant elsewhere (see Figure 2-3). Poland’s electricity consumption rose by 1.6% in 2018, putting it 12% above 2010 lev- els and, in terms of growth, second only to Lithua- nia. In western European countries, consumption was below 2010 levels, with the UK having reduced electricity consumption most. As said above, elec- trification of heat and transport is expected to raise electricity consumption everywhere in the coming decade.
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Heat dissipation from a stationary brake disc, Part 2: CFD modelling and experimental validations

Heat dissipation from a stationary brake disc, Part 2: CFD modelling and experimental validations

2.1. Volume Mesh Generation Initial modelling of airflow around a complex shape, such as a ventilated brake disc, driven purely by buoyant affects has proven difficult. Olphe-Galliard [1] found that a much larger volume has to be considered, compared to the axisymmetric models often used in dynamic braking simulations, such as Voller [2] and Galindo-Lopez [3]. Furthermore, a much finer volume mesh was required, including prism layers close to the surface boundaries, giving greater near-wall shear stress evaluation. Building on the previous work, Figure 1b shows the rectangular geometry encased around a standard 434/234 mm radial vane commercial vehicle (CV) brake disc, making the CFD volume mesh. The geometry extended 1.0 m downwards in the negative Y direction and in both the positive and negative X direction from the origin (located on the flange face plane, on the disc centreline), 0.5 m from both the flange and the inboard contact faces (Z directions), whilst extending a further 2.5 m above the disc brake (positive Y). The consequence of such a large area is that the CFD solver had to make calculations for a total volume of 3.795 m 3 . Having to use a relatively fine mesh over such a large volume will inherently cause
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The European power sector in ...:

The European power sector in ...:

and politically viable strategies for ensuring the success of the clean energy transition in Germany, Europe and the rest of the world. As a think tank and policy laboratory we aim to share knowledge with stakeholders in the worlds of politics, business and academia while enabling a productive exchange of ideas. Our scientifically rigorous research highlights prac- tical policy solutions while eschewing an ide- ological agenda. As a non-profit foundation primarily financed through philanthropic dona- tions, we are not beholden to narrow corporate or political interests, but rather to our commit- ment to confronting climate change.
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Hybrid power plant - Concept for coupling MGT and SOFC

Hybrid power plant - Concept for coupling MGT and SOFC

The turbo-components for a hybrid power plant have to be very robust as the SOFC integrated in the micro gas turbine cycle and increases pressure loss significantly, changes retention time and temperatures in between compressor and turbine. The compressor is limited by the so called surge line [5]. A stable operation across this line is not possible. Passing the surge line leads to compressor surge – a short flow reversal leading to high pressure fluctuations in the whole system. The experiments showed that there is also the possibility of constant backflow with this compressor as the volume of the vessel and the piping system in between compressor and turbine is very high. This would cause damages at both systems. The SOFC material could break and on the MGT side this leads to overcurrent in the generator resulting in an emergency shutdown and a damage of the bearings. Therefore, the compressor’s most important characteristic is to show a large surge margin. As the SOFC is responsible for the main electrical power output, the efficiency of the MGT power module is of lower interest compared to the surge margin.
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Coupling geomechanics and transport in naturally fractured reservoirs

Coupling geomechanics and transport in naturally fractured reservoirs

usually over-estimated (high oil-water ratio) because the matrix blocks contain far more fluid than fracture networks and in a single porosity model, water is more likely to stably displace the oil front toward production wells. In reality, in most cases with aggressive drawdown, water breakthrough occurs early in the fractures and matrix block oil displacement is small. Different solutions have been proposed to “slow down” the oil movement and “speed up” the water movement in grid blocks where fractures are present. One of the typical solutions is the use of Local Grid Refinement (LGR) where fractures are represented explicitly via thinner lines of grid blocks. An additional permeability is added to the thinner block to account for the fractures [Henn et al., 2000]. LGR requires more computational time due to the increase in the number of grid blocks and is impractical for complex fracture patterns. Numerical difficulties may arise as a result of large flow rates in thinner grid blocks with small pore volume such as when a water tongue develops rapidly in fractures due to gravity segregation. Henn et al. (2000) addressed this problem by applying vertical lumping to thinner grid blocks containing fractures.
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Coupling geomechanics and transport in naturally fractured reservoirs

Coupling geomechanics and transport in naturally fractured reservoirs

Figure 12. Real and geometrical fracture element representation [Granet et al., 2001] x Finite Element Method (FEM) The Finite Element Method (FEM) is based on a piecewise representation of the solution in terms of specified basis functions. FEM consists of three fundamental steps, which are: domain discretization, local approximation, and global matrix assembly and solution [Jing, 2003]. 7KH SUREOHP¶V GRPDLQ LV discretized into a finite number of subdomains (finite elements) with a regular shape and fixed number of nodes. The field variables are then written as a trial function of its nodal value in a polynomial form (i.e. weak form). Appropriate test functions are multiplied by the weak form of the governing equations, and then integrated over each element. The results are then assembled into a global matrix, and by solving the linear system of equations therein, the value of field variables at each integration point is determined.
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Coupling XFEM and peridynamics for brittle fracture simulation—part I : feasibility and effectiveness

Coupling XFEM and peridynamics for brittle fracture simulation—part I : feasibility and effectiveness

The simulated displacement fields for each of the cases considered are presented in Fig. 10 . In the same figure, a black dotted line is used to indicate the coupling interface ∂Ω 1 in Case 3. For easier comparison the plots have been created using the same colour scales. Additionally, in Fig. 11 , the plate is plotted in its deformed state for Case 3. The intro- duction of the shifted Heaviside enrichment at the elements cut by the crack, enables the FE method to facilitate dis- continuous displacement fields and capture the displacement jump at the crack body. It is this property that allows the PD domain to be limited only in the area near the crack tip, without unmerging nodal displacements or specifically con- structing the FE mesh to conform to the crack geometry. This will prove invaluable in the following paragraphs were crack propagation problems are considered. Notice also how using the definition from Eq. 14 the ghost particles that are posi- tioned within an enriched element follow its deformation.
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The MATSim Open Berlin Scenario: A multimodal agent-based transport simulation scenario based on synthetic demand modeling and open data

The MATSim Open Berlin Scenario: A multimodal agent-based transport simulation scenario based on synthetic demand modeling and open data

A subsequent manual scenario calibration is carried out using the selected output plans of the previous step (cf. Sec. 2.3) as input plans, together with the original network (without up-scaling). An openly available GTFS dataset for the Berlin-Brandenburg region [17] is used to generate MATSim public transport schedule and vehicles files and to add public transport links to the network. In contrast to the previous calibration step, this calibration is done manually and without any influence of CaDyTS. That is, the agents’ scores solely depend on the generalized time- and distance- related travel cost as well as the time spent performing activities. Person agents are enabled to change their modes of transport, departure times, and routes. Besides ‘car’ (as driver), the available modes of transport include ‘ride’ (i.e. car as passenger), ‘public transport’, ‘bicycle’, and ‘walk’. In the current scenario, all modes besides car and public transport are so-called teleported modes, i.e. trips made by these modes are handled by putting the agent to the location of the next activity with a time lag. For walk and bicycle, the time lag corresponds to the beeline distance and a mode-specific speed (cf. Tab. 2). For the ride mode, the agents are routed on the network and the teleportation time is obtained from the (congested) travel time of the car mode along that route. During the calibration process, the ride mode share was fixed and agents are not allowed to switch from or to the ‘ride’ mode. For trip chains starting and ending at the same activity location, the transport mode may be changed to car or bicycle (i.e. chain-based modes) for the whole tour or a combination of public transit and walk. In addition, agents are enabled to randomly shift their departure times within a range of 2 hours. For activities with durations larger than 2 hours, the end time is adjusted and for activities with durations smaller than 2 hours, the activity duration is changed. Furthermore, agents are enabled to adjust their routes. Freight agents are only enabled to change their route. To obtain more realistic free- speed travel times, the free speeds of inner-city street from OpenStreetMap are reduced by its half in order to account for traffic lights, acceleration and deceleration at intersections etc. An explicit modeling of traffic signals is possible via a corresponding extension [9] if data on signals of the study are accessible, which is currently not the case in Berlin. Simulation settings are stated in Tab. 1, where innovative strategies include transport mode choice, departure time choice, and route choice. The mode-specific parameters, which have been adjusted in this calibration step and constitute the result of this step, as well as other predefined mode-specific settings are given in Tab. 2. For all scoring function parameters not shown in Tab. 1, MATSim’s corresponding default values are used [13].
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Logistics and Transport Organization for the Food Retail: A Comparative Analysis between France and Germany

Logistics and Transport Organization for the Food Retail: A Comparative Analysis between France and Germany

The palm oil industry in Ghana is dominated by four large plantation companies that primarily supply the domestic manufacturing industries (notably the food and soap industry); exports of palm oil are unstable and relatively insignificant. In order to ensure sufficient supply and legitimacy in the local communities, three out of the four plantation companies have established outgrower schemes. The participating farmers are supported with land preparation, seedlings, fertilizers, extension services, etc. on a loan basis while signing contracts that expose them to the vagaries of the world market for vegetable oils. The schemes have had mixed results but generally not fulfilled the local socio-economic goals set out by companies, involved farmers and state institutions, including local authorities. This paper examines the development of a scheme in the Kade area, Eastern Region. The scheme was started in the early 1980s and considered as relatively successful until the turn of the century, but during the recent decade it has increasingly encountered problems. Conflicts between the plantation company and the outgrowers escalated to such an extent that the scheme in essence was dismantled in 2010. However, a number of spinoff effects from the scheme are gradually emerging: Firstly, oil palm has generally become at least as important as cocoa suggesting a diversification of cash crop production. Secondly, artisanal and medium-scale industrial production of palm oil for local and regional markets (primarily Nigeria) has increased substantially. This paper outlines the causal factors behind the new dynamics and discusses the sustainability of the regional economy as a complex outcome of interacting world market dynamics, competition from other sectors (notably mining), regional trade agreements and domestic agricultural policies. In conclusion the paper offers some lessons for the design and implementation of resilient outgrower schemes in Africa.
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Sector Surcharges for Temporary Agency Workers in Germany: A Way Out of the Low-Wage Sector?

Sector Surcharges for Temporary Agency Workers in Germany: A Way Out of the Low-Wage Sector?

employment; and (3) deficiencies in fairness when one compares pay levels between agency workers and permanent staff. (1) Displacement of Permanent Staff by Agency Workers There is anecdotal evidence for the fact that companies sometimes decrease their permanent staff in favor of agency workers (see Dauser 2009 and Wetzel & Weigand 2011). However, looking beyond isolated incidents of displacement, the real question is whether such displacement is widespread and, by extension, macroeconomically significant. Several statistical analyses comparing change in the number of temporary workers and the number of permanent staff within a firm or sector find no evidence to support the displacement hypothesis (see Crimmann et al. 2009 and Baumgarten & Kvasnicka 2012). However, newer empirical evidence based on a macroeconomic model does suggest that in the period up to 2010, while additional jobs were created, displacement also occurred (see Jahn & Weber 2013). The authors conclude, “If one considers, for example, an increase in the number of agency workers by 200,000 (such as occurred in the boom years of 2006 or 2010), about 100,000 jobs were displaced from outside the temporary agency work sector, but a total of 100,000 additional employment relationships were created” (Jahn & Weber 2013, p. 5).
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On the strategy for power sector development in the Kaliningrad Region

On the strategy for power sector development in the Kaliningrad Region

Conclusion. There is a set of specific and complicated problems in the Kaliningrad power complex, which are to be solved by covering several as- pects. Firstly, it is the improvement of the generation complex development programme based on technical and economic analysis and technocenotic ideas. Here, one should take into account the interests of the industry (first of all those of power generation entities and consumers), the multifactor prog- noses of power consumption and all financing opportunities. Considering the regional generation complex, one should not overlook the construction of the nuclear power plant; however, there are still questions to be addressed. How will the NPP integrate into the regional power complex, how will it affect the regional infrastructure, how will it integrate into the power systems of neighbouring countries? The existent power plants are to be modernised and switched to widely available fuel (including coal). Moreover, it is crucial to construct five-seven smaller 30-60 MW and 40-50 smaller 1-3 MW CHPPs. A part of electricity demand can be still met by means of transit via the terri- tory of Lithuania under either the current or a new scheme. It can be lucra- tive in the framework of the general energy balance and increase the stability of power supply. Finally, in order to ensure operation under special condi- tions, it is essential to create a backup regional generation complex. Sec- ondly, there is a need for legislative support to the projects of development of wind and hydropower as well as other alternative energy sources, which conforms to the optimal variant and is advantageous in terms of environ- mental protection. One should keep in mind that, without legislative support, this sector of power generation does not develop in any country of the world. Thirdly, there is a need to introduce into the energy management system of the Kaliningrad region the methodology of optimal management of regional electrotechnical complex, which will eliminate the threat of power shortage, which emerges in the condition of uncontrolled power consumption growth. Fourthly, it is necessary to establish in the Kaliningrad region a research and consulting centre (possibly, a technology park) aimed to draw up a general concept and an improved programme of the development of regional power industry, including the formulation of and operation plan of supply to con- sumers during special periods, the coordination of operation and division of responsibilities.
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TransAID Deliverable 2.2: Scenario definitions and modelling requirements

TransAID Deliverable 2.2: Scenario definitions and modelling requirements

The core of this scenario is finding gaps in the motorway’s right-most lane (that is not part of the on-ramp). C(A)Vs are guided to these gaps with speed advice, because even with very low traffic volume they could arrive right next to other vehicles in the merging area by chance in the absence of guidance. If the available gaps are not large enough to allow the safe and smooth merging of on- ramp vehicles, speed and lane advices are also provided to the CAVs and CVs driving on the main road, thereby creating the necessary gaps in traffic to facilitate the smooth merging of on-ramp vehicles. Thus, gaps are created by the exchange of suitable lane change advices to these two kinds of vehicles; AVs and LVs do not receive information. In addition, advice to vehicles is only given within a certain action-zone, i.e. upstream of and at the merge location. Beyond that, further downstream, vehicles can default back to their previous own behaviour. Combining this with ramp- metering algorithms to control the in-flow of vehicles to the motorway, will open more possibilities for traffic management as the inflow can temporally be halted when the gap creation measures would be too disruptive.
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