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European Network engaging CIvil society in Low Carbon scenarios

Final Report Summary - ENCI-LOWCARB (European network engaging civil society in low carbon scenarios)

Executive summary:

In recent years an ever-growing number of energy scenarios have been published. The urgency of the effects of climate change translates into more and more contrasting, complementary and even opposing narratives for the necessary energy transition. In most cases, the scenarios are technically feasible and respecting physical boundaries, but this does not mean that they are necessarily politically, economically or socially acceptable.

Within the Seventh Framework Programme (FP7) project ENCI-LOWCARB researchers and civil society organisations (CSOs) developed and applied a reproducible methodology for a collaborative scenario creation process that aimed to integrate civil society input in a transparent way. Energy scenarios were developed for Germany and France that had transparently integrated opinions from national stakeholders into the applied modelling tools and so into the resulting climate change mitigation scenarios.

The main outcomes of the project were:

1. developing and refining innovative hybrid modelling tools Remind-D and Imaclim-R that represent explicitly monetary values and physical quantities so as to capture the specific role of the different energy sectors and their interaction with the rest of the economy
2. establishing a cooperative relationship between CSOs and researchers to build energy scenarios together despite diverging cultural approaches. A reproducible methodology for collaborative scenario creation processes was developed.
3. collaboratively creating energy mitigation scenarios for Germany and France and ensuring a sense of ownership for these scenarios among the participating stakeholders.

The French scenario mainly focuses on the necessary composition and interaction of specific acceptable sets of policy measures (laws, taxes and economic incentives) aimed at getting France on a climate friendly pathway. Several bottlenecks and leverage points were identified, such as the imminent need to adopt a carbon tax that could trigger funding for a transition. Importantly, if only those measures that were judged acceptable by the consulted stakeholders were implemented, France would only achieve a 68 % carbon dioxide (CO2) emission reduction compared to 1990, significantly less than the French climate objective (75 % of greenhouse gas emissions in 2050). An important challenge is to create stronger commitment among stakeholder for more ambitious policy measures.

The three German mitigation scenarios all achieved a fixed 85 % CO2 emission reduction objective. Their focus is on the interdependencies of the different sectoral activities and trade-offs that have to be made between energy sectors if stakeholders consider a specific development likely or desirable. The stakeholder dialogues revealed strong discrepancies between likely (continuation scenario) and desirable future developments (paradigm shift scenarios) in the transport and electricity sector. Carbon lock-in in the 'continuation scenario' would slow down economic growth and bear severe socio-political externalities. To overcome these trade-offs, carbon lock-ins have to be avoided and, additionally, energy efficiency and renewable deployment growth rates have to increase. Participating stakeholders pointed out that in order to resolve the carbon lock-in, major paradigm shifts are needed, which in turn require concerted political as much as societal will.

The methodology for collaborative scenario creation processes that was developed and applied during this project is replicable and could serve as a possible blueprint for the development of scenarios that are open to stakeholder participation, such as official multi-stakeholder scenario creation processes coordinated by the government, regional scenario development processes led by local authorities, or even European Union (EU) wide scenario developments like the EU energy roadmap.

The ENCI-LOWCARB research project identifies a number of principles that should guide scenario-building processes to ensure they are inclusive and participatory:

1. the knowledge and understanding on what are the main drivers of the modelling tool that is used must be shared among the stakeholders that participate in a scenario creation process
2. there should be transparent rules on how to integrate stakeholder contributions in the modelling features that are systematically applied in practice
3. the scientists and coordinators responsible for a collaborative scenario creation process must be neutral when it comes to the technology choices and must not state preferences on policy measures or climate or energy objectives
4. the core of the future scenarios should be built based on stakeholder contributions. It is the role of the project team to translate the visions of different stakeholders into the modelling tool.

Project context and objectives:

Climate change has already become a reality, we are suffering biodiversity loss, besides we continue to deplete our resources, and we are accepting incredible injustices concerning the development levels of the different continents with billions of people suffering and over-consuming in the same time. Even institutions like the Institute for Environmental Assessment (IEA) raise alarm. In addition, the Organisation for Economic Cooperation and Development (OECD) states that without additional measures the CO2 concentration at the end of the century will achieve 685 ppm which corresponds to an average temperature increase of about 3 to 6 °C.

More and more people become aware of this approaching disaster for nature and humanity and the last decade is characterised by an always-growing number of energy scenarios and visions. The urgency of the upcoming impacts of climate change translates into more and more contrasting, complementary and even opposing narratives on the necessary energy transition.

In most cases these scenarios are technically feasible and respecting physical boundaries but this does not mean that they are politically, economically or socially acceptable.

This is why energy scenarios are now in many cases based on public or stakeholders consultations in order to check or assure their acceptability. However, few exercises attribute importance to the scenario design process and explain in a transparent way how stakeholder contributions are taken into account and integrated in the modelling tools, that is to say how the translation process was carried out from an idea supported by contributors to its representation in the resulting scenario.

Technical feasibility is no longer considered being a sufficient trigger for transformation – governments and stakeholders have to initiate the transformation process as a collective project for a common future; political, economic and social acceptability is essential. As a first step acceptable mitigation scenarios are needed supported by the ownership of national stakeholders.

However, the French case study also shows that if pathways are only built on a set of policy measures that is acceptable by a majority of stakeholders then the resulting CO2 emission reductions won't be ambitious enough to ensure the necessary French contribution for respecting the limit of a 2 °C average temperature increase.

Objectives of the project:

1. develop and refine hybrid modelling-tools that are able to represent technical sectoral details and at the same time the interplay with an economic system
2. create a reproducible methodology for a collaborative scenario design process
3. raise awareness among the community of researchers and CSOs about the importance of collaborative scenario creation processes - between researchers and non-governmental organisations (NGOs), and between both and other stakeholders - and their design. Spread knowledge about the project results and the reproducible methodology for a collaborative scenario design that was developed, via seminars and a mailing list.
4. elaborate acceptable mitigation scenarios for France and Germany in a collaborative process including an internal cooperative process between researchers and CSOs and a second external collaborative step between the project team and national stakeholders.

The main results of the project are:

1. the development and refinement of the innovative hybrid modelling tools Remind-D and Imaclim-R France that represent explicitly values and physical quantities so as to capture the specific role of energy sectors and their interaction with the rest of the economy.
2. the establishment of a successful cooperation of CSOs and researchers on the topic of energy scenarios benefitting from cross-fertilisation between the diverging approaches of project partners from distinct professional culture backgrounds. The development of a blueprint project design enabling quantitative modellers, social scientists, and non-governmental organisation members to jointly develop project-specific interdisciplinary research methods for addressing technological and sociological dimensions at once. Within this process the main result was the development of a reproducible methodology for a collaborative scenario creation design.
3. dissemination of the project results was effectuated via regular newsletters, project websites, a 'low-carbon-network' mailing list, the organisation of EU stakeholder seminars, low-carbon network seminars and project conferences
4. the elaboration of collaboratively built energy mitigation scenarios for Germany and France and creation of ownership for these scenarios among the participating stakeholders.

Development and refinement of hybrid modelling tools

The modelling tool Remind-D for Germany was developed by the Potsdam Institute for Climate Impact Research (PIK). It is a Ramsey-type growth model that integrates a detailed bottom up energy system module, coupled by a hard link. It facilitates an integrated analysis of the long-term interplay between technological mitigation options in the different sectors of the German energy system as well as general macroeconomic dynamics. The objective of REMIND-D is to maximise welfare, i.e. the intertemporal sum of discounted logarithmic per capita consumption.

Strengths of the Remind-D model compared to other macroeconomic/energy-system models refer especially to the mechanism of optimisation and furthermore to the endogenous representation of the sectors in the energy system and macroeconomics. Furthermore it can be shown which technologies could contribute to emission reduction and how a welfare-optimising transformation could look like.

The modelling tool Imaclim-R for France was developed by the International Centre for Environment and Research (CIRED). It is a computable general equilibrium model and it calculates the evolution of the French economy split into 15 sectors: energy sectors, transport sectors, construction, energy-intensive industries, agriculture and services.

The Imaclim-R model computes, between 2004 and 2050, the evolution of the economy and the energy system with a strong consistency. That means it is explicitly representing both monetary values and physical quantities so as to capture the specific role of energy sectors and their interaction with the rest of the economy.

The existence of explicit physical variables (e.g. number of cars, number of dwellings or energy efficiency of technologies) allows an incorporation of sector-based information about how final demand and technical systems are transformed by economic incentives. In Imaclim-R, each year the equilibrium provides a snapshot of the economy and gives gross domestic product (GDP), sectoral prices, sectoral investments, households' consumption in each sector, unemployment rate and international trade. Two successive annual equilibria are linked by 'dynamic sectoral modules'. These sectoral modules represent the specific sector dynamics given economic and physical constraints.

A limitation of Remind-D and Imaclim-R France is that it computes only energy-related CO2 emissions and other greenhouse gases are not represented. The modelling tools were developed and refined by the research partners of the project. A collaborative scenario creation methodology was developed based on a transparent integration of contributions of national stakeholders in both countries. The process was divided in three phases.

Mitigation scenarios were developed collaboratively for France and Germany by the project team based on stakeholder contributions. The used modelling tool shaped the specific form and focus of the different scenario processes.

The French scenario is mainly focusing on the necessary composition and interaction of specific acceptable sets of policy measures (laws, taxes and economic incentives), aiming at getting France on a climate friendly pathway. If only those measures that are judged acceptable by the consulted stakeholders are implemented a 68 % CO2 emission reduction compared to 1990 can be achieved which is less than the French climate objective (75 % of greenhouse gas emissions in 2050). Moreover this level of reduction is highly sensitive to energy prices and technology assumptions. An important challenge is to create stronger commitment among stakeholder for more ambitious policy measures.

Several bottlenecks and leverage points were identified for example the imminent need for the adoption of a carbon tax triggering funding for transition or the need for the adoption of a refurbishment obligation for dwellings.

The three German mitigation scenarios are all achieving a fixed 85 % CO2 emission reduction objective. Their focus is on the interdependencies of the different sectoral activities and trade-offs that have to be made between energy sectors if stakeholders consider a specific development likely or desirable. The stakeholder dialogues revealed strong discrepancies between likely ('continuation scenario') and desirable future developments (paradigm shift scenarios) in the transport and electricity sector. Carbon lock-in leads in the 'continuation scenario' will slow down economic growth and bear severe socio-political externalities. To overcome these trade-offs, carbon lock-ins have to be avoided and, additionally, energy efficiency and renewable deployment growth rates have to increase. Participating stakeholders pointed out that in order to resolve the carbon lock-in, major paradigm shifts are needed, which in turn require concerted political as much as societal will.

Project results:

Methodology

The innovation of the ENCI-LOWCARB project resides besides the resulting energy scenarios in the process itself. The project hypothesis consisted in stating that if national stakeholders can recognise their contributions in the resulting scenarios they would eventually be more supportive of this scenario than in a case where a non-transparent procedure was followed. Using collaborative procedures can increase stakeholders' acceptance and generate political support for energy scenarios and the resulting policy measures. Reaching this positive outcome also implies more involvement for both stakeholders and modellers, particularly in terms of time and shared understanding of the issues at stake and of the functioning of the used modelling tool.

The aim of the ENCI-LOWCARB project was to develop a collaborative scenario creation methodology and to develop scenario for France and Germany based on a transparent integration of contributions of national stakeholders in both countries.

Phase one: Intra-group development of the project team

Albeit the intra-group development of project teams is a fairly standard procedure, a conscious group-formation process is of particular importance for collaboration across project partners from different communities. Tuckman (1965) observed that groups generally develop by passing through four distinct stages: forming, storming, norming and performing. Given project partners from different communities with their respective cultural backgrounds, the first three stages need special attention for being successful in the fourth.

A promising format to foster viable cross-cultural communication is to employ formal 'wish-lists'. The research institution receives features that the NGO partners would like to see in the model and what kind of results they expect. The social scientist receives ideas on how social acceptance is defined and will be explored, interpreted and measured. The NGO member receives considerations on what kind of stakeholders to consult. Thereby, each project partner gets a good understanding on how the others perceive his/her discipline. Each project then presents what he/she originally planned to contribute in the project and relates this to the 'wish-list' items. Finally, in thematic sessions, the history and status quo of the domestic energy system can be presented, so one learns facts and context of the other country's challenges.

Phase two: Technological framework conditions

Within the ENCI-LOWCARB project, one challenge was the use of macro-economic hybrid models for the scenario design task, which are often characterised as 'black-boxes'. This implies at least a basic introduction to the model dynamics at the attention of the NGO project partners and the invited experts and stakeholders.

During the ENCI-LOWCARB project, it was very important for the NGO members to learn more about quantitative models in general, and the models of the project partners in particular, so that modelling results can be put into perspective. It was a rather time-intensive process for the quantitative modellers to explain the models and was perceived as a real cross-cultural communication effort. During this process, it was very enlightening for the modellers to learn about the requirements from an NGO perspective, which sometimes differs substantially from academic peer group discussions.

In France and Germany sectoral expert meetings were organised in order to assess the degree of economic and technical realism of the modelling tools and to correct and to update exogenous hypotheses as well as dynamics of the models itself: investments in the electricity sector or the dynamics of the residential sector. The task is to refine the national quantitative models and bring them to a stage, in which they are applicable to stakeholder consultations, fulfilling as many 'wish-list' items as feasible, driven by the overarching question of 'What is technically possible in the future'.

Phase three: Political framework conditions and corresponding scenarios

A central issue in phase three of the collaborative scenario definition process is to apply a framework that makes it possible to integrate in transparent way stakeholder contributions in the scenario modelling process. The term stakeholders refer to societal actors like trade unions, consumer associations, private businesses, energy companies etc.

Project process in France

The collaborative scenario creation process within phase three of the project in France was divided in different steps:

1. stakeholder mapping, identification of the national stakeholders
2. organisation of sectoral stakeholder meetings
3. translation of stakeholder contributions in modelling parameters
4. organisation of a transversal feedback seminar.

Project process in Germany

A central issue in phase three of the collaborative scenario definition process was the elaboration of different and potentially controversial political framework conditions with relevant CSO stakeholders. The political framework conditions relate to the quantitative model by applying the aforementioned translation rules from model parameters to 'real-world implications'. Coherent sets of political framework conditions form one scenario, differing with respect to the articulated level of social (un-)acceptability of mitigation options. The integrated scenarios are again evaluated by the CSO stakeholders.

Before inviting CSO stakeholders, the sub-national project teams identified sectors of the domestic energy system that are of particular interest or controversy regarding social acceptance. Together with a professional and neutral moderator, the national sub-teams developed concrete workshop agendas. The social scientist selected suitable methods for capturing stakeholder's assessments during the workshops. A practical format that was chosen was a questionnaire with Likert scales, measuring the level of agreement or disagreement of the respondent towards specific statements. Stakeholders were unlikely to express a uniform opinion, so several different sectoral 'scenario building-bricks' in terms of political framework conditions emerged from the workshops.

Due to the small sample size, the data is not suited for econometric analysis. Instead, descriptive statistic measures of central tendency were employed. Along with the qualitative information obtained during the discussions as well as expert judgments from the literature, the elicited data serves as a basis for generating a set of parsimonious narratives on likely developments, and one on desirable developments in the transport and electricity sector. Finally, the modelling team translates these into corresponding input parameters for the model Remind-D.

During the second sectoral stakeholder workshops, ideally attended by the same CSO representatives, the developed scenarios were presented, discussed, and evaluated. This feedback loop ensures that the social acceptance considerations are actually realised and gives the CSO representatives a chance to indicate their assessment of social (un-)acceptance of the integrated scenarios.

The stakeholder workshops were the focal point toward which all efforts in the ENCI LOWCARB projects were directed to. However, it was absolutely necessary to go through the first two phases of intra-group and model development for reaching a stage in which the project team was enabled to understand the stakeholders' requirements and translate them into coherent quantitative model scenarios. The preparation of the first stakeholder workshop was very demanding, as the agenda set here would determine the success of the collaborative procedure.

Phase four: Synthesis

The last phase is concerned with the synthesis of results obtained throughout the collaborative process. The project results were presented at a project conference in Paris and during other conferences and seminars to policy makers, stakeholders, and the wider public. The project publications were published on the project websites (see http://www.lowcarbon-societies.eu and http://www.enci-lowcarb.eu online) and send via e-mail and mail to national and European stakeholders.

German scenarios

Remind-D is a Ramsey-type growth model that integrates a detailed bottom up energy system module, coupled by a hard link. It facilitates an integrated analysis of the long-term interplay between technological mitigation options in the different sectors of the German energy system as well as general macroeconomic dynamics.

An underlying assumption of the macroeconomic production function of Remind-D regards Germany as a closed economy without individual actors demanding or producing any commodities. The national GDP, produced from the three production factors capital, labour and energy, has to cover the costs of energy systems and investment in the macroeconomic capital stock. The rest remains to increase welfare. Thereby the welfare of the whole society is being maximised, not only the GDP. There is one representative household and furthermore full employment is assumed. Of course these adoptions are not in accordance with reality; nevertheless they are necessary for optimisation models. Restrictions resulting from this remain especially that Remind-D can neither analyse effects on employment of climate change policies nor does it consider the role of individual actors or the question of distribution. Moreover, the algorithm of optimisation leads per se to more climate mitigation costs in ambitious scenarios of CO2 emission reduction, as it would be the case in less ambitious scenarios.

Strengths of the Remind-D model compared to other macroeconomic/energy-system models refer especially to the mechanism of optimisation and furthermore to the endogen representation of the sectors in the energy system and macroeconomics. Remind-D features optimal annual mitigation effort and technology deployment as a model output. Available mitigation options fall into four categories:

1. deploying alternative low-emission technologies,
2. substituting final energy and energy service demands,
3. improving energy efficiency and
4. reducing demand.

The model generally avoids the latter, as demand reductions have negative impact on GDP.

Three model-based mitigation scenarios for Germany were developed within the ENCI-LOWCARB project. All three achieve 85 % CO2 emission reduction in 2050 relative to 1990. These scenarios were defined and evaluated in a participatory process with CSO stakeholders from the transport and electricity sector. During dialogues, their preferences on future mitigation options were discussed and elicited. Along with findings from the literature, the input from the CSO stakeholders built the basis to generate parsimonious narratives on possible future developments of key variables in the transport and electricity sector.

The 'continuation' scenario is characterised by a set of developments that are deemed highly likely by all participants. These include the dominance of motorised individual transport, unabated coal electrification, moderate energy efficiency growth rates, local resistance against windmills and transmission lines as well as the continuation of coupled freight transport and GDP growth rates.

The two 'paradigm shift' scenarios reproduce future developments judged as desirable by participating stakeholders. These include a decrease in total freight transport mileage, a shift in the modal split of freight transport sector from road to rail, a substantial increase of public and non-motorised transport in the modal split of passenger transportation, a phase-out of conventional coal electrification until 2020, a rapid and large-scale deployment of renewable electricity generation and transmission line capacities as well as a fourfold increase in energy efficiency growth rates.

Model results corroborate that achieving an ambitious mitigation target of 85 % German CO2 emission reduction by 2050, relative to 1990, is technically feasible. However, this research unravels that critical socio-political externalities may pose a significant barrier to ambitious domestic mitigation. Deliberative stakeholder dialogues reveal strong discrepancies between likely and desirable future developments in the transport and electricity sector. Model results indicate that enforcing ambitious mitigation targets in the face of this carbon lock-in leads economic growth to slow down and bears severe socio-political externalities. To overcome these trade-offs, the carbon lock-in has to be avoided and, additionally, energy efficiency and renewable deployment growth rates have to increase. Participating stakeholders point out that in order to resolve the carbon lock-in, major paradigm shifts are needed, which in turn require concerted political as much as societal will.

Scenario results

The model Remind-D finds an optimal solution for each of the scenario configurations, despite the strict emission budget of 16 GtCO2. All scenarios achieve 85 % CO2 emission reduction in 2050 relative to 1990; corroborating the finding that ambitious domestic mitigation in Germany is technically feasible. Yet, the scenario results in the following Sections indicate that a continuation of historical trends in the freight and electricity sector, deemed likely, leads to a carbon lock-in that renders ambitious mitigation extremely challenging.

Mitigation shares of the three sectors transport, electricity and heat structurally differ across scenarios. Even if the overall annual CO2 emissions in million tons (Mt) CO2 of the paradigm shift scenarios are the same, the sectoral contributions are different for each scenario.

The total carbon lock-in over the time horizon of analysis, 2005 to 2050, amounts to 6.15 GtCO2 from coal electrification and 2.67 GtCO2 from fossil fuel based freight transport. In sum, these 8.8 GtCO2 deplete 55% of the total emission budget. Consequently, the heat sector needs to deliver a substantially higher mitigation effort in the 'continuation' scenario than in the two 'paradigm shift', in order to meet the total CO2 emission budget.

Until 2050, total CO2 emissions within the transport sector decrease by 47 % in the 'continuation', 73 % in the 'paradigm shift' and 93 % in the 'paradigm shift+' scenario versus 2005. The majority of annual reductions are achieved during the next two decades, yet the drivers differ across the three scenarios. Clear structural breaks emerge in both modal splits in the two 'paradigm shift' scenarios. In all scenarios, freight transport by inland water navigation remains constant. In the 'continuation' scenario, freight train capacities also remain at today's levels, however, freight transport with trucks increases continuously, as enforced by the scenario assumption of coupled GDP and freight transport growth rates. Apart from keeping freight transport mileage constant at today's level, through a restructuring the economic system towards less transport-intensive value chains, mitigation is enabled by massive rail infrastructure expansions allowing for train mileage to tripe until 2030.

The structural change in both 'paradigm shift' scenarios becomes evident concerning the total annual p-km by transport mode: motorised individual transport (MIT) decreases until 2050 and public transport (PT) steadily increases until 2020, remaining constant thereafter. Hybrid buses, electrified light rail and regional trains deliver additional short distance PT. Together, they account for roughly 50 % of the modal split of short distance transport in 2050. Incremental long distance PT will be delivered with electric trains. In all scenarios, anticipated carbon budget restrictions and implicit carbon pricing make conventionally fuelled cars too expensive to operate, so they are phased out entirely until 2030. Diesel cars, predominantly suitable for long distance driving, are first substituted by diesel hybrids and then by hybrid gas cars in all scenarios. Petrol cars are replaced with hybrid-plug in gasoline cars, which are electric cars with a petrol-fuelled rage extender. In the 'paradigm shift+' scenario, they are partly replaced with hydrogen hybrid cars, as hydrogen is produced from lignocelluloses with carbon capture and sequestration (CCS) here, with the ability to extract CO2 from the atmosphere and producing de-facto 'negative' CO2 emissions. In all scenarios, there is a trend to gradually electrify the transport sector, with the total demand of electricity for transport increasing by several orders of magnitude until 2050, yet never exceeding 15 % of total electricity production.

In the two 'paradigm shift' scenarios, where the model is given the option to decommission existing hard coal and lignite power plants from 2015 onwards, these capacities are shut down by 2020. They are temporarily replaced by gas turbines, about 25 GW of capacity are built between 2015 and 2020. Once enough renewable energy generation (REG) capacity is installed, the gas turbines go out of service again in both 'paradigm shift' scenarios by 2030. In the 'continuation' scenario, there is no such temporary increase in gas capacities, as existing coal and lignite power plants continue to produce electricity. In all scenarios, REG is rapidly expanded and doubling over the next five years.

From 2020 onwards, the installed REG capacities stagnate in the 'continuation' scenario. This is due to the moderate potential in the scenario definition, motivated by a restrictive public attitude that constrains the incremental deployment of RE capacities and transmission lines. Total electricity production is forced to decrease from 620 MWh in 2005 to 375 MWh. Because of the carbon lock-in from freight transport and coal electrification, the model cannot afford to allocate more CO2 from the emission budget to the electricity sector for covering gas turbines. These could provide more balancing capacities so that solar potentials could be fully exploited, which is not the case in the 'continuation' scenario. Instead, Remind-D opts for the least attractive mitigation option: imposing electricity demand reductions in all sectors, including industry. A consequence of this is a reduction in GDP growth.

In both 'paradigm shift' scenarios, REG capacities continuously expand, especially offshore wind, and total electricity production stabilises between 530 and 560 MWh. The slightly reduced demand is due to high efficiency growth rates. In 2050, onshore wind capacities reach a maximum of 100 GW in both 'paradigm shift' scenarios. Offshore capacities reach 150 GW in the 'paradigm shift' scenario and 180 GW in the 'paradigm shift+' scenario. Geothermal electricity production also plays a vital role in all scenarios with 20-35 GW installed capacity. Remind-D installs 110 GW of solar photovoltaic in the 'continuation' scenario by 2050. In the 'paradigm shift' scenarios, other less expensive technologies provide sufficient electricity generation potential and solar photovoltaic plays only a minor role. Biomass electrification plays a subordinate role in all scenarios. In the 'paradigm shift+' scenario, 14 GW of lignite power plants with the oxyfuel CCS technology are installed, as well as 25 GW of natural gas combined cycle plants with CCS. When compared to the 'paradigm shift' scenarios, these capacities somewhat reduce the need for REG capacities.

Comparing the results of two scenarios that differ only with respect to the emission constraint, allows for the determination of the effects of different mitigation choices. One measure of economic mitigation costs is the cumulative difference in discounted GDP losses, between two scenario runs that have the same restrictions, except for the size of the CO2 emission budget. Macroeconomic mitigation costs in terms of cumulative GDP losses for the 'continuation', 'paradigm shift' and 'paradigm shift+' scenario amount to 3.5 %, 1.4 % and 0.8 % between 2005 and 2050. For more ambitious targets, the mitigation costs in the 'continuation' scenario increase relatively faster than in the two 'paradigm shift' scenarios. This divergence is induced through the differences in scenario assumptions.

CSO stakeholders perceive three projected developments in the 'continuation' scenario as implausible, due to socio-political externalities that conflict with other policy arenas. Firstly, the model results indicate a strong decrease of motorised individual transport that is not compensated for by more PT mileage. Massive state intervention would be necessary to induce behavioural changes of such magnitude. The CSO stakeholders assess that such policies will lack social acceptance and strongly emphasise the value of individual mobility in modern societies. Secondly, the required electricity and heat demand reductions are considered as politically not enforceable in reality. To induce such a development, again, rigorous carbon pricing policies would be required, which would increase the price of electricity and heating. Thirdly, the CSO stakeholders doubt that the projected CO2 emission reductions and efficiency improvements in the heat sector can be realised, seeing institutional barriers as for example the well-known landlord-tenant conflict of responsibility. In sum, these critical socio-political externalities motivated the CSO stakeholders to assess the 'continuation' scenario as highly undesirable, despite the fact that it reaches the required mitigation target. The 'paradigm shift' scenarios see the carbon lock-in resolved. CSO stakeholders prefer the 'paradigm shift' scenario over the 'paradigm shift+' scenario as they predict substantial public protest against the large-scale deployment of CCS infrastructure and biofuel production.

French scenarios

Imaclim-R France is a computable general equilibrium model. This model was used for the collaborative scenario design process of French energy scenarios within the project ENCI-LOWCARB.

It models the evolution of the French economy split into 15 sectors: energy sectors (crude oil, refined oil, gas, coal and electricity), transport sectors (freight terrestrial transport, water transport, air transport, public road passenger transports and rail passenger transport), construction, energy-intensive industries, agriculture and services.

The Imaclim-R model computes, between 2004 and 2050, the evolution of the economy and the energy system with a strong consistency. This is why Imaclim-R is what is called a hybrid model compared to economic models or to technical models. In Imaclim-R, energy is explicitly representing values and physical quantities so as to capture the specific role of energy sectors and their interaction with the rest of the economy. The existence of explicit physical variables (e.g. number of cars, number of dwellings or energy efficiency of technologies) allows a rigorous incorporation of sector-based information about how final demand and technical systems are transformed by economic incentives. Imaclim-R France is an open economy model. Thus, an important modelling assumption is that crude oil; gas and coal prices are exogenous and are calibrated on the world energy outlook report by the International Energy Agency (2011). A limitation of Imaclim-R France is that it computes only energy-related CO2 emissions and other greenhouse gases are not represented.

The collaborative scenario design process relies on Imaclim-R France for integrating all the inputs from stakeholders. Therefore, the modelling tool strongly determines the form of the interaction with stakeholders, the format of the meetings as well as the manner to discuss the issues.

The energy scenario for France that has been developed within the ENCI-LOWCARB projects presents a set of policy measures and technical variables that were judged 'acceptable' by at least half of the selected stakeholders. No emission budget or target has been fixed in advance to the scenario process. The emission reductions in the scenario are only based on those policy measures that are acceptable in the eyes of the stakeholders. But even if those measures are not ambitious enough to achieve the necessary climate targets some of them are still too ambitious for the actual policy agenda (especially a carbon tax).

During the stakeholder meetings that were organised within the interactive scenario creation process stakeholders were asked to outline their vision on the evolution of the global climate framework. Stakeholders considered that consumption styles in Europe and in France remain material-intensive. This is why changes in consumption styles or consumers' preferences were not part of this scenario. Nevertheless a decoupling of growth and resources use was further investigated in a sensitivity analysis. In this French mitigation scenario no global climate agreement is reached; climate policies coordination only exists at the EU level. This situation leads to a world with a high-energy demand and to high fossil energy prices. Energy prices follow the world energy outlook' 2011, as required by the stakeholders. Because of this high fossil energy prices, technological innovation focuses on renewable and energy efficiency, as well as on carbon capture and sequestration.

The integration of all measures considered acceptable by at least half of the stakeholders lead to CO2 related energy emissions equal to 126 Mt CO2. The sectoral contribution lead to a 60 % decrease in emissions compared to 2010 and 68 % compared to 1990.

The decarbonisation of the electricity sector is difficult between 2015 and 2025 with the first wave of nuclear plants decommissioning. During this transition period, gas plants are built which induces new emissions for the electricity sector. To limit these 'transition emissions', priority has to be given to very ambitious energy efficiency measures to decrease electricity demand during this transition period and to the development of renewable energies on the short term.

A wide range of policy measures and economic incentives has been judged acceptable by at least half of the stakeholders that participated in the scenario creation process. These measures either need investments or produce incomes, but the overall economic balance of the scenario is positive.

The total electricity production increases over the scenario period from 50 million tons of oil equivalent (Mtoe) to 60 Mtoe in 2050. This increase of 20 % is relatively low compared to the threefold increase in the same amount of time between 1973 and 2010. The main sectors responsible for the increase are the industrial and tertiary consumption mainly because gas is substituted by electricity.

The stakeholders disapproved the construction of new power plants for exports so the electricity exports in this scenario are rapidly declining. The partial fuel switch from gas to electricity in the industry sector takes place before 2020. On the contrary, the consumption of the services steadily increases at a rate exceeding 2 % before 2025 and around 1 % afterwards. The electricity consumption of energy producing industries (for example oil refineries) decreases slowly. Electricity transport losses are following proportionally the increasing electricity consumption. Residential uses other than primary heating decrease before 2020 (from 9 to 8 Mtoe) and increase until 10 Mtoe after 2020. Due to more and more new electricity devices (especially multi-media), the consumption especially for these energy services increases over the scenario period. Traditional domestic electricity services decrease with increasing energy efficiency. Before 2030, the consumption of electric vehicles does not appear on the graph; it increases until 2040 and stabilises at 0.6 Mtoe. The electricity prices for households show a sharp increase between 2010 and 2020, climaxing at 41 % in 2020 compared to 2010. The share of renewables in the electricity mix is 20 % in 2020 and 50 % in 2050. In addition, 43 GW of nuclear plants are extended during 20 years.

The period between today and 2025 is the most critical one. Indeed, the beginning of nuclear plants' decommissioning, in addition to the growing share of variable renewables and the uncertainties surrounding the electricity supply market induce the construction of power plants fuelled by fossil energies.

Over the scenario period, the existing building stock shows a progressive disappearance of the low-efficiency classes G to D, and a gradual penetration of classes C due to economic incentives and learning-by-doing which decreases retrofitting costs. Most of the retrofitted stock reaches class C in 2050. Nearly no ambitious retrofit to class B or A appear, since these retrofitting options remain too costly for households given the economic incentives and energy prices in the scenario. Even the existence of an obligatory renovation fund for jointly-owned buildings and the availability of third-party financing do not decrease the risk aversion of the owners of individual houses and jointly-owned buildings enough to make such ambitious transitions happen. In all subcategories of existing buildings transitions to upper energy classes appear jointly with an important energy substitution from gas and fuel towards electricity for heating that corresponds in the model to a significant penetration of heat pumps. Given a behaviour function, the model computes the gap between the theoretical energy consumption for heating and real energy consumption after a retrofit action or in new energy efficient buildings, e.g. the rebound effect. Concerning energy uses other than primary heating in residential, the shares of gas and fuel remain stable.

Globally, the final energy consumption (heating and other uses) per capita is divided by two and the total final energy consumption decreases by 37 % between 2010 and 2050. The CO2 emissions of the residential sector decrease of 75 % between 2010 and 2050. The households' expenditures for energy consumption, refurbishment and construction in the residential sector decrease over the scenario period from 6 to 4.5% of the overall household budget.

In the scenario, two mitigation strategies are implemented for passenger mobility, i.e. limiting current increase in individual mobility with urban planning and incentives to limit voluntarily mobility demand. The bonus-malus measure is calibrated from 2010 to 2050 to result in a positive or neutral financial balance for the government. Moreover, the scenario is based on the biofuel development scenario in the world energy outlook 2006. A technology switch takes place around 2030 concerning the first-generation ethanol production towards second-generation biofuels as production costs of the latter decrease. On average, the mitigation scenario leads to a slight increase of individual mobility on the long term. This translates with the population growth into a 19 % increase of total passengers' mobility. The objective of policies and measures implemented for urban mobility is the limitation of the increase of urban sprawl, while favouring more collective transport infrastructures. Because of the inertia of the existing system, these measures begin to have a significant impact only after 2030. The widening of congestion in urban areas decreases the time available for long journeys particularly with a more expensive air transport (kerosene tax) and inertia in the development of road alternatives. This explains partly the decrease in total passengers' mobility in 2030. The eco-tax for heavy trucks enhances technical change towards more efficient technologies. In 2030, the energy efficiency of heavy trucks is 25 % higher. Overall, the emissions of the freight terrestrial sector decrease by 40 % between 2010 and 2050. The fiscal measures applied to the transport sector positively impact the financial balance of the government, except for the domestic consumption tax on petroleum products whose receipts decrease significantly over time. For the infrastructural investments, all the operations are done neutrally if compared to the reference scenario.

The population follows the 2010 National Institute of Statistics and Economic Studies (INSEE) central demographic scenario and equals 72.3 million in 2050, i.e. a 15 % increase compared to 2010. The impact is particularly positive from 2025 to 2035. At this date, the electricity price in the mitigation scenario is around 25 % lower than in the reference scenario. Moreover, fossil energy prices get much more expensive than in the reference scenario because of the carbon tax. The combination of both factors induces a substantial energy switch towards electricity for productive sector and households. In addition, energy efficiency measures induce a decrease of the energy expenditures in the household budgets and for services industries that are not energy-intensive, which furthermore reinforces the international competition of French goods. The development of non-fossil energies in conjunction with energy efficiency measures constitutes a protection against the negative impacts of the increase in energy prices and of the French import dependency.

A number of policies have been suggested to address concerns over competitive losses due to one country introducing a carbon tax while another country does not. In this variant, the impact of the implementation of a border tax adjustment (BTA) at the EU27 level was analysed. This additional measure is computed alone in a first scenario, and a second scenario gathers the BTA and previous assumptions related to decoupling and reshoring. Logically, the direct impacts of the BTA are a reinforced international competitiveness, but also an increase of consumer prices.

A question that is outwearing the end of this scenario creation exercise and that needs further research is how to reconcile stakeholders' acceptance and ambitious climate objectives. As the 'acceptable mitigation scenario' is not ambitious enough to reach the necessary climate targets in terms of emission reductions, a second scenario was developed including additional measures. These measures that were not approved by the stakeholders achieve nevertheless a 75 % CO2 emission reduction in 2050 compared to 1990 and are the following:

1. A carbon-energy tax (CET): the carbon tax is replaced by a carbon-energy tax to give a further incentive to reduce energy consumption. It taxes the energy content and the carbon content of the energy and is applied to all the forms of energy (coal, gas, oil, nuclear) except renewable energies.
2. A refurbishment obligation is applied to the building stock. The planning of the obligation is organised following the type of building and the energy label of the building, beginning with the less energy-efficient classes.

The emissions reductions following the implementation of all the measures that were judged acceptable by at least half of the stakeholders come close but fail in reaching the 'factor four' target. The package of measures leads to a 68 % CO2 emissions reduction only in 2050 compared to 1990. Nonetheless, the factor four is reached in the residential sector as well as the power sector. The crucial issues lie with the contributions of the transport sector and the productive sectors to tackle emissions. In the transport sector, the evolution of emissions will heavily depend on mobility, strongly driven by urban sprawl. The predominance of road for transportation and the yearning for more mobility, intertwined with the transformation of urban patterns in France will determine the shape of the energy transition.

This project has revealed elements of consensus regarding climate mitigation policies but also some cleavages. Two measures that were not consensual among stakeholders appear crucial in actually reaching the factor four objective, namely the refurbishment obligation for the existing building stock and the energy-carbon tax (instead of a carbon tax only). This reveals the need for a strong political commitment to leverage the decarbonisation of the energy system. The responsibility lies with the stakeholders and the government to decide on a hierarchy of values and actions fed by scientific evidence and public concerns.

Potential impact:

Potential socio-economic impact and the wider societal implications of the project

Need for stakeholder implication in scenario creation processes

The last decade is characterised by an always-growing number of energy scenarios and visions. In most cases these scenarios are technically feasible and respecting physical boundaries but this does not mean that they are politically, economically or socially acceptable. We are facing a situation where scientifically founded energy scenarios exist that are based on available technology choices often even being source of economic and social benefits, but the political framework and support is lacking to adopt them.

The ENCI-LOWCARB project deployed one strategy to find a commonly accepted solution, i.e. a participative methodology starting from the hypothesis that a scenario co-developed by researchers and stakeholders is more likely to be accepted by the wider public. If stakeholders develop ownership for the energy scenario because their vision is integrated part of the presented pathways and they share a common understanding on limits and necessary decisions then chances are higher for a political support. The gathering of stakeholders in the frame of the scenario workshops in France and Germany showed the existing awareness of stakeholders. The project team noticed a common understanding concerning the urgency for action against climate change but many actors feel trapped in the actual system based on fossil energy consumption. The meetings created exchanges and connections between societal actors and researchers lasting also beyond the end of the project.

Need for clear translation rules in collaborative scenario processes

One of the major outcomes of the ENCI-LOWCARB project with potential implications on other scenario creation processes is the need for clear translation rules. If stakeholders are associated to a scenario process aiming at integrating their visions in a comprehensive scenario it is important that all participants know the 'rules of the game'.

A transparent definition of the framework in advance to the process is important to provide a common starting point for all stakeholders. This framework should include clear information on the translation rules and the form stakeholder contributions should take in order to match with the model requirements and the scope of the process. Even if this claim seems evident, within our investigation about existing scenario processes at the beginning of the ENCI-LOWCARB project we have not found one single process that made a clear statement on the translation process. The requirement to clearly state in advance the translation rules should be integrated in all stakeholder based scenario processes; especially those initiated by the government or other official public bodies. These translation rules should be as clear as possible within the limits of the used modelling tool.

Need for conscious design of scenario creation processes in line with the scope of the exercise

The design of a scenario creation process has to be conscious about a series of modelling needs and assumptions. It is not enough saying that stakeholders have to be consulted or associated to a process; the means have to be coherent with the objective of the project. If a scenario process is based on stakeholder consultations there should be an ex-ante acceptance concerning the choices of the stakeholders. If the scenario result is already known at the beginning of the process the choice of the participating stakeholders or the process in itself will be biased; in this case one should preferably speak of a normative scenario based on stakeholder contributions rather than of a collaborative scenario process.

Need for a transparent explanation of limits and opportunities of the modelling tools

Substantial differences exist in the approaches and underlying assumption for energy economic modelling. The European project Recipe compared three macro-economic modelling tools and captured their different behaviour under the same set of variables. Also both modelling tools that were used within the ENCI-LOWCARB project were part of the model selection. Imaclim-R is a recursive-dynamic computable general equilibrium model with a special focus on inertia in the development and deployment of new technologies. Remind, by contrast, is an optimal growth model that simulates optimal development pathways for maximising intertemporal welfare.

The study shows the diverging approaches of both modelling tools. Imaclim-R is not based on perfect foresight and computes important economic transition costs in the beginning of the scenario period in order to overcome system inertia. Nonetheless in the end of the period the losses are lower than concerning the other two models because the transition speed was higher. But the overall consumption losses of the Remind-R scenario are still lower because it is based on intertemporal optimisation.

Hence it is not surprising that the choice of the modelling tool also has an impact on the organisation of the stakeholder contributions. Stakeholders have to be aware of the dynamics and drivers of the used modelling tool in order to avoid the feeling that they are dealing with a 'black box' and that their contributions have no impact and will in any case not be traceable. One recommendation of the ENCI-LOWCARB project is to provide the stakeholders with a short written description of the modelling tool and to allocate time for an in-depth presentation and discussion at the first stakeholder meeting.

Need for highlighting interdependencies and 'branches in the scenario road'

The energy scenarios that were developed within the ENCI-LOWCARB project for Germany and France contain a number of policy relevant messages.

The French scenario is mainly focusing on the necessary composition and interaction of specific acceptable sets of policy measures (laws, taxes and economic incentives) aiming at getting France on a climate friendly pathway. Several bottlenecks and leverage points were identified:

1. to overcome the inertia of the energy system it is of eminent importance that as soon as possible a carbon tax is adopted in order to finance the reconstruction of the energy system
2. if only economic incentive are developed and no planned retrofitting obligation is adopted house-owners won't exploit the whole energy efficiency potential of the retrofitting
3. stakeholders are not in favour of an electrification of the transport sector
4. stakeholders are in favour to stop investments in road construction and a reallocation of this funding for public transport
5. stakeholders believe that a reduction of electricity production for electricity exports is desirable
6. the allocation of carbon tax revenues has an impact on consumer electricity prices and unemployment rate
7. the economic balance of the mitigation scenario remains positive over the time period
8. the scenario shows that if there will be a lack of planning of the electricity production facilities transition emissions will be generated due to the necessary construction of fossil power plants
9. if only those measures that are judged acceptable by the consulted stakeholders are implemented a 68 % CO2 emission reduction in comparison to 1990 can be achieved, which is less than would be necessary and even less than the French climate objective. An important challenge is to push stakeholder acceptance further to create consensus around even more ambitious policy measures.

The three German mitigation scenarios are all achieving an ex-ante fixed 85 % CO2 emission reduction objective. Their focus is on the interdependencies of the different sectoral activities and trade-offs that have to be made between energy sectors if stakeholders consider a specific development likely or desirable. As said before, all scenarios achieve the same emission reduction target. Nonetheless the liberty chosen by the first parsimonious narrative or scenario to accept a continuation of climate-damaging activities, is at the origin of several so said carbon lock-ins in some of the sectors which is thus requiring 'buy-backs' on other sectors to respect the overall carbon budget.

Further increasing freight transport mileage as enforced by the scenario assumption of coupled GDP and freight transport growth rates are producing committed emissions. These emissions are counterbalanced by highly restricted per capita passenger km transport. The electricity sector in the 'continuation' scenario is also representing a carbon lock-in leading to a sub-optimal emission allocation.

The stakeholder dialogues revealed strong discrepancies between likely and desirable future developments in the transport and electricity sector. The carbon lock-in leads in the 'continuation scenario' will slow down economic growth and bear severe socio-political externalities. To overcome these trade-offs, carbon lock-ins have to be avoided and, additionally, energy efficiency and renewable deployment growth rates have to increase. Participating stakeholders pointed out that in order to resolve the carbon lock-in, major paradigm shifts are needed, which in turn require concerted political as much as societal will.

Need for bringing the outputs in the actual policy debate

The stakeholder dialogues organised within the ENCI-LOWCARB project showed that the detailedness of the visions and the existence of a consensus among the invited stakeholders about concrete steps, decisions and a schedule leading towards a climate friendly future varies depending on the sector. The work of the ENCI-LOWCARB scenarios allowed identifying bottlenecks in France and Germany. These subjects have to be discussed further and brought to the policy agenda:

1. decoupling of freight transport and GDP growth
2. making an early decommissioning of coal power plants acceptable
3. adoption of a progressive carbon tax on energy consumption
4. the need for a planned retrofitting obligation for buildings.

Dissemination activities and exploitation of results

During the project the main dissemination activities were:

1. the organisation of regular EU stakeholder seminars in Brussels
2. the participation in EU events like the Green Week and the EUSEW
3. the organisation of regular 'low carbon society network' seminars, promoting use of the project methodology for registered NGOs and researchers
4. dissemination of results over project newsletter, the mailing list of our ENCI-LOWCARB network and other relevant mailing lists
5. the presentation of preliminary results in other scenario related contexts
6. dissemination of results over the project websites
7. meetings with public institutions to discuss the recommendations of the scenarios
8. presentation of the project results and especially of the collaborative scenario creation methodology for interested parties
9. assisting interested NGOs and researchers involved in the development of low carbon scenarios and strategies with stakeholder involvement in European countries.

The project has inspired a number of initiatives for collaborative development of low-carbon scenarios and strategies with stakeholder involvement. Based on contacts made during the project the International Network for Sustainable Energy (INFORSE) Europe developed a project proposal for developing scenarios with stakeholder involvement together with national partners in Bulgaria, Italy, and Latvia for these three countries. In parallel to this, INFORSE-Europe has become associate partner to a project to develop scenarios for the southeast European countries. The project also inspired a Hungarian INFORSE member to develop low-carbon scenarios for Hungary. Additionally, Polish CSOs have been interested in the project, and some participated in project events. Also INFORSE-Europe is using methods and lessons from the project for its projects with local scenarios and strategy projects. An Indian investment company is planning to develop a multi stakeholder climate scenario for India focusing on infrastructure development.

List of websites:

Public websites

Permanent website with the contacts of the project partners and all project reports: http://www.enci-lowcarb.eu/

Network website including contacts, reports, a collection of other existing mitigation scenarios, newsletters, subscription possibility to a mailing list: http://www.lowcarbon-societies.eu