Decarbonisation Scenarios Research Articles

The early retirement challenge for fossil fuel power plants in deep decarbonisation scenarios

Rapid decarbonisation of the global energy sector will likely have a multitude of economic consequences, including the premature decommissioning of most fossil fuel power plants. In this analysis, we examine the impact of early retirements for oil, coal, and natural gas-fired generators required to follow a given 2 °C emissions trajectory (the IEA 2DS) and explore the policy implications surrounding this challenge. Modelling the period up to 2060, the drop in retirement age required to meet this scenario potentially creates $541 billion worth of stranded power plant assets across the US, EU, China, and India alone. In some cases, coal plants built within the past 5 years will need to be retired after only half the nominal operating lifetime. Regional analysis exposed disproportionate impacts in China and India, shouldering the vast majority of the costs and amplifying concerns over energy access and affordability. Policies such as burden-sharing for equitable mitigation, investment into CCS technology, and international financial compensation are discussed as potential avenues for mitigating this impact. However, limitations in all avenues highlight the need for further consideration of the inferred requirement to force early retirements, in order to avoid exacerbating regional imbalances and improve the feasibility of imposed targets.

An environmental evaluation of food waste downstream management options: a hybrid LCA approach

PurposeFood waste treatment methods have been typically analysed using current energy generation conditions. To correctly evaluate treatment methods, they must be compared under existing and potential decarbonisation scenarios. This paper holistically quantifies the environmental impacts of three food waste downstream management options—incineration, composting, and anaerobic digestion (AD).MethodsThe assessment was carried out using a novel hybrid input–output-based life cycle assessment method (LCA), for 2014, and in a future decarbonised economy. The method introduces expanded system boundaries which reduced the level of incompleteness, a previous limitation of process-based LCA.ResultsUsing the 2014 UK energy mix, composting achieved the best score for seven of 14 environmental impacts, while AD scored second best for ten. Incineration had the highest environmental burdens in six impacts. Uncertainties in the LCA data made it difficult determine best treatment option. There was significant environmental impact from capital goods, meaning current treatment facilities should be used for their full lifespan. Hybrid IO LCA’s included additional processes and reduced truncation error increasing overall captured environmental impacts of composting, AD, and incineration by 26, 10 and 26%, respectively. Sensitivity and Monte Carlo analysis evaluate the methods robustness and illustrate the uncertainty of current LCA methods. Major implication: hybrid IO-LCA approaches must become the new norm for LCA.ConclusionThis study provided a deeper insight of the overall environmental performance of downstream food waste treatment options including ecological burdens associated with capital goods.

Assessment of decarbonisation scenarios for the residential buildings of Serbia

Thermal energy demand in the residential building sector represents a big challenge for Serbia. In order to understand how to reduce this demand, and thereby avoiding GHG gas emissions, a bottom-up simulation model was developed. The model built the business-as-usual and two decarbonization scenarios up to 2030. For each scenario, such results as useful and final energy consumption, associated CO2 emissions, energy costs, investment costs and others were prepared at each level of the building stock segmentation. To develop such a detailed model, the topology of the residential building stock was developed and used as an input. For each individual building type, three retrofit packages of different stringency were analyzed. The paper delivers several important messages for the decarbonization of Serbia. First, it argues that the level of thermal energy services consumed by Serbian households is inadequate to address their needs. Second, the households of Serbia are likely to consume more wood than it was reported by national energy balances. Third, thermal energy efficiency retrofits can significantly reduce household energy demand at the same time as offering higher thermal comfort. However, the required investments are high and therefore benefits beyond energy cost savings should also be considered in order to make the transition to the low energy building stock economically feasible. <br><br><font color="red"><b> This article has been corrected. Link to the correction <u><a href="http://dx.doi.org/10.2298/TSCI181228017E">10.2298/TSCI181228017E</a><u></b></font>

Closing the carbon cycle to maximise climate change mitigation: power-to-methanolvs.power-to-direct air capture

In order to meet the 1.5−2C target, with CCU, it is necessary to close the carbon cycle, and avoid partial decarbonisation scenarios. In this context, direct air capture appears more effective than CCU.

Overcoming the financial barrier to a low emission development strategy in Brazil

This paper presents two low GHG emission scenarios for Brazil up to 2050, and discusses the impact in the implementation of a deep decarbonization scenario of a financial device allowing for decreasing capital costs of mitigation investments. Specifically, we consider (i) a governmental plan scenario assuming the achievement of NDC targets up to 2030 and the extension of current policies up to 2050; and (ii) a deep decarbonization scenario leading to a national GHG emission pathway compatible with an international effort targeted to stabilize the global temperature at 1.5 °C above pre-industrial levels. We present a comparative analysis of the scenario results for key economic and social indicators, and simulate the adoption of a new financial device allowing to decrease capital costs of low carbon investments in Brazil. Our conclusions highlight the potential of innovative financial mechanisms to foster the transition to a low carbon society in developing countries, as illustrated in the case of Brazil.

Pathways to Decarbonise the European Car Fleet: A Scenario Analysis Using the Backcasting Approach

This paper analyses decarbonisation scenarios for the European passenger car fleet in 2050. The scenarios have been developed using the backcasting approach and aim to reduce greenhouse gas (GHG) emissions of passenger cars to a level defined in the Transport White paper that is 60% below 1990 levels. Considering the emission levels of 2010, a yearly reduction of 1.7% is required in order to achieve the target. Car emissions were decomposed into the main emission factors of mobility, efficiency and carbon intensity. How these factors change over time depends on various external factors: the pace of technological improvements, the future role of cars in society’s mobility system and the priority given to decarbonising energy demand. The analysis showed that if car mobility and ownership continue to increase as expected in a ‘business as usual’ case, a share of 97% plug-in hybrid or battery electric vehicles might be required by 2050, together with a substantial decrease in greenhouse gas emission from electricity production. A transition to more advanced car technology such as automated driving, advanced batteries or lightweight materials in vehicle production would raise vehicle efficiency. Should car mobility continue at a high level, an early technology transition will be required.

Water demand for electricity in deep decarbonisation scenarios: a multi-model assessment

This study assesses the effects of deep electricity decarbonisation and shifts in the choice of power plant cooling technologies on global electricity water demand, using a suite of five integrated assessment models. We find that electricity sector decarbonisation results in co-benefits for water resources primarily due to the phase-out of water-intensive coal-based thermoelectric power generation, although these co-benefits vary substantially across decarbonisation scenarios. Wind and solar photovoltaic power represent a win-win option for both climate and water resources, but further expansion of nuclear or fossil- and biomass-fuelled power plants with carbon capture and storage may result in increased pressures on the water environment. Further to these results, the paper provides insights on the most crucial factors of uncertainty with regards to future estimates of water demand. These estimates varied substantially across models in scenarios where the effects of decarbonisation on the electricity mix were less clear-cut. Future thermal and water efficiency improvements of power generation technologies and demand-side energy efficiency improvements were also identified to be important factors of uncertainty. We conclude that in order to ensure positive effects of decarbonisation on water resources, climate policy should be combined with technology-specific energy and/or water policies.

Detailed Modelling of the Deep Decarbonisation Scenarios with Demand Response Technologies in the Heating and Cooling Sector: A Case Study for Italy

Energy policies accompanying the transition towards a sustainable development process must be supported by technical analyses in which future energy scenarios are modeled and evaluated. This paper analyzes possible decarbonization scenarios in Italy for the year 2050. They envisage high electrification of transports and residential buildings, high use of renewable energies, and a modal shift towards public transport. The energy scenarios are evaluated using a software program, EnergyPLAN, starting from a reference model developed for the year 2014. Special attention has been given to the modeling of data that are unavailable in the literature, such as the time profile of heating and cooling demands, obtained with the degree-days method and validated by elaborating the results of the modeling of the residential building stock, this latter was dynamically simulated in TRNSYS. The results show that to obtain a significant decrease of greenhouse gas emissions and fossil fuel consumption, it is necessary not only to promote a deeper penetration of renewable sources, but also their integration with other technologies (cogeneration, trigeneration, power-to-heat systems, thermal storage, vehicle-to-grid operations). In fact, renewables technologies alone can raise some critical issues, such as excess and/or shortage of electricity production and non-sustainable exploitation of biomass.

Designing a Model for the Global Energy System—GENeSYS-MOD: An Application of the Open-Source Energy Modeling System (OSeMOSYS)

This paper develops a path for the global energy system up to 2050, presenting a new application of the open-source energy modeling system (OSeMOSYS) to the community. It allows quite disaggregate energy and emission analysis: Global Energy System Model (GENeSYS-MOD) uses a system of linear equations of the energy system to search for lowest-cost solutions for a secure energy supply, given externally defined constraints, mainly in terms of CO2-emissions. The general algebraic modeling system (GAMS) version of OSeMOSYS is updated to the newest version and, in addition, extended and enhanced to include e.g., a modal split for transport, an improved trading system, and changes to storages. The model can be scaled from small-scale applications, e.g., a company, to cover the global energy system. The paper also includes an application of GENeSYS-MOD to analyze decarbonization scenarios at the global level, broken down into 10 regions. Its main focus is on interdependencies between traditionally segregated sectors: electricity, transportation, and heating; which are all included in the model. Model calculations suggests that in order to achieve the 1.5–2 °C target, a combination of renewable energy sources provides the lowest-cost solution, solar photovoltaic being the dominant source. Average costs of electricity generation in 2050 are about 4 €cents/kWh (excluding infrastructure and transportation costs).

Is the optimal decarbonization pathway influenced by indirect emissions? Incorporating indirect life-cycle carbon dioxide emissions into a European TIMES model

Energy system optimization models (ESOMs) such as MARKAL/TIMES are used to support energy policy analysis worldwide. ESOMs cover the full life-cycle of fuels from extraction to end-use, including the associated direct emissions. Nevertheless, the life-cycle emissions of energy equipment and infrastructure are not modelled explicitly. This prevents analysis of questions relating to the relative importance of emissions associated with the build-up of infrastructure and other equipment required for decarbonization.We have soft-linked an environmentally-extended input-output (EEIO) model to a European TIMES Model (ETM-UCL) with the aim of addressing the following questions:-In what ways does the inclusion of indirect emissions change the optimal technology pathway for decarbonizing the European energy system?-How much does the present value of key low-carbon technologies change when indirect emissions are accounted for in a decarbonization scenario for Europe?We show that, although indirect emissions are a relatively small portion of overall power sector emissions (<10% in 2050), including them in the model leads to changes in the optimal power sector portfolio. Renewable energy technologies become relatively less attractive once indirect emissions are included within the optimization framework, and we quantify this effect, showing that it is not large. Changes to the relative attractiveness of specific renewable energy technologies are more pronounced than the reduction in attractiveness of renewable energy as a whole: in our main scenarios wind energy saw increased relative deployment in 2050 when indirect emissions are accounted for, since it displaced other technologies with higher life-cycle emissions (notably solar PV). Optimal cumulative installed capacity of PV in the EU 2050 is at least 7% lower when indirect emissions are included. We conclude that policy advice derived from ESOMs that focuses on the roles of specific technologies should ensure that it is robust to the possible effects of indirect emissions.

India's Energy and Emissions Future: A Synthesis of Recent Scenarios

Global perceptions of India’s climate and energy future have changed rapidly. From a concern that Indian energy needs could jeopardise climate futures, India is increasingly seen as a forerunner of a low carbon future. This Perspective synthesizes scenario studies to more accurately delineate India’s future energy and carbon trajectory and explores the conditions that will shape alternative futures. We conclude that, based on current policies, a doubling of India’s CO2 emissions by 2030 from 2012 levels is a likely upper bound, and that this trajectory is consistent with meeting India’s Paris emissions intensity pledge. Policy scenarios suggest scope for reduced emissions growth, but this scope is more limited in national development-based scenarios than pure decarbonisation scenarios. Conditions that will drive future emissions include the energy-intensive nature of India’s future job creation, the ability to lock-in energy efficient measures, and the sustainability of recent renewable energy price trends.

Tracking sectoral progress in the deep decarbonisation of energy systems in Europe

Decarbonisation of energy systems requires deep structural change. The purpose of this research was to analyse the rates of change taking place in the energy systems of the European Union (EU), in the light of the EU's climate change mitigation objectives. Trends on indicators such as energy intensity and carbon intensity of energy were compared with decadal benchmarks derived from deep decarbonisation scenarios for the electricity, residential, transport, and industry sectors. The methodology applied provides a useful and informative approach to tracking decarbonisation of energy systems. The results show that the EU has made significant progress in decarbonising its energy systems. On a number of indicators assessed the results show that a significant acceleration from historical levels is required in order to reach the rates of change seen on the future benchmarks for deep decarbonisation. The methodology applied provides an example of how the research community and international organisations could complement the transparency mechanism developed by the Paris Agreement on climate change, to improve understanding of progress toward low-carbon energy systems.

Combined economic and emission dispatch considering conventional and wind power generating units

Combined economic and emission dispatch (CEED) is an optimization solution to the short-term demand and supply balancing in the power network. Given that wind power is playing an increasing role in the UK, this paper develops a CEED model for a combined conventional and wind power system under the UK energy policies. The proposed model aims to determine the optimal operation strategy for the given system with the consideration of wind power curtailment and reservation and also the environmental aspect, especially the carbon price of greenhouse gases (GHG) and emission limits of decarbonisation scenarios. From two case studies, increasing the carbon price at a low emission limit leads to an increase in the total cost, but the rate of the increase is mitigated on decreasing the emission limits. Moreover, dispatch is dominated by the carbon price at high emission allowance levels and by the emission allowance at low emission allowances.

A comparison of land-use requirements in solar-based decarbonization scenarios

What is needed to achieve decarbonization in the United States of America? While recent scholarship has presented detailed scenarios for consideration, further analysis is needed into their implications and the scale of social, institutional, and policy changes that will be necessary for implementation. This communication examines one component of a transition to an energy system based on solar power: the scale and pace of land-use change that would be necessary to realize the widespread use of utility-scale solar photovoltaic (PV) technology envisioned in these scenarios. How much land would be required to deploy the proposed generating capacities for utility-scale solar PV, under a uniform set of assumptions? How does the envisioned change to solar land-use compare to historical episodes of rural settlement? By answering these questions, we focus attention on policies that permitted earlier changes to occur, and the possibilities for similar measures to be adopted in a solar transition.

System Optimization and Co-benefit Analysis of China's Deep De-carbonization Effort towards its INDC Target

In 2015, China has submitted its Intended Nationally Determined Contribution (INDC) to UNFCCC, and committed to reduce the emission intensity per unit of GDP by 60%–65% from its 2005 level in 2030, and also peak the carbon emission around 2030. At the same time, the local pollutant problem and haze problem keeps getting worse in China. This paper focuses on these challenges and critical research topic on co-control of carbon emission and local air pollutants, and evaluate the co-benefit of carbon mitigation on the local pollutant reduction. The work is based on China-MAPLE model framework, a partial equilibrium model with linkage between carbon emission and local air pollutants at technological level. Compared to the reference scenario, in the deep de-carbonization scenario, energy consumption and carbon emission will obviously decreased and the current pollutant control measures are in urgent to be improved; in the Co-control scenario with China's peaking effort, the emission of SO2, NOX and PM2.5 in 2030 will be reduced by 78.85%, 77.56% and 83.32% compared to the level of 2010, which means with the peaking target be fulfilled, the air quality targets can also be achieved.

The role of an exergy-based building stock model for exploration of future decarbonisation scenarios and policy making

State-of-the-art research suggests that energy systems are best evaluated using exergy analysis, as exergy represents the real value of an energy source, demonstrating it to be the only rational basis for evaluation. After discovering the lack of thermodynamic integration into stock modelling, this paper presents the development of an exergy-based building stock model. The aim of this paper is twofold. Firstly, to investigate the impact of large-scale future energy retrofit scenarios in the English and Welsh (E&W) non-domestic sector, and secondly, to determine the potential of exergy analysis in improving sectoral efficiency and its potential implications on exergy-oriented policy making. The research explores seven different large-scale future retrofit scenarios that encompass typical, low-carbon, and low-exergy approaches. Modelling results show that by 2050, current regulations have the potential to reduce carbon emissions by up to 49.0±2.9% and increasing sector thermodynamic efficiency from 10.7% to 13.7%. On the other hand, a low-exergy oriented scenario based on renewable electricity and heat pumps is able to reduce carbon emissions by 88.2±2.4%, achieving a sectoral exergy efficiency of 19.8%. This modelling framework can provide energy policy makers with new insights on policy options based on exergy indicators and the assessment of their potential impact.

A roadmap for rapid decarbonization.

Emissions inevitably approach zero with a “carbon law”

A Rapid Urban De-carbonization Scenario Analysis Tool

A rapid urban de-carbonization scenario analysis tool has been developed. The tool is able to efficiently and effectively generate and populate spatially resolved large scale building scenes, to generate XML input files for the building energy simulation engine CitySim [1], to quickly modify building thermal attributes and develop and analyze de-carbonization scenarios as snapshot modifications to the building scene. The tool has been developed as a series of plugins to the Quantum Geographical Information System (QGIS) [2] application, whereby it can make use of much of the QGIS existing functionality and software libraries. A tip to tail test of the tool is performed on a basic scenario.

Designing a Global Energy System Based on 100% Rwables for 2050: GENeSYS-MOD: An Application of the Open-Source Energy Modelling System (OSeMOSYS)

This paper develops a path for the global energy system up to 2050, presenting a new application of the open source energy systems model OSeMOSYS to the community. It allows quite disaggregate energy and emission analysis: GENeSYS-MOD (Global Energy System Model) uses a system of linear equations of the energy system to search for lowestcost solutions for a secure energy supply, given externally defined constraints, mainly in terms of CO2-emissions. The General Algebraic Modeling System (GAMS) version of OSeMOSYS is updated to the newest version and, in addition, extended and enhanced to include e.g. a modal split for transport, an improved trading system, and changes to storages. The model can be scaled from small-scale applications, e.g. a company, to cover the global energy system. The paper also includes an application of GENeSYS-MOD to analyze decarbonization scenarios at the global level, broken down into 10 regions. Its main focus is on interdependencies between traditionally segregated sectors: electricity, transportation, and heating. Model calculations suggests that in order to achieve the 1.5°-2° C target, a combination of renewable energy sources provides the lowest-cost solution, solar photovoltaic being the dominant source. Average costs of electricity generation in 2050 are about 4 €cents/kWh (excluding infrastructure and transportation costs).

Energy system impacts and policy implications of the European Intended Nationally Determined Contribution and low-carbon pathway to 2050

In March 2015 the European Union (EU) submitted to the United Nations Framework Convention on Climate Change (UNFCCC) the Intended Nationally Determined Contribution (INDC) in view of the Paris Conference of Parties (COP21). The binding target of lowering domestic greenhouse gases emissions by at least 40% by 2030 compared to 1990 levels, coupled with long-term decarbonisation goals, will have profound energy system, macroeconomic and policy implications. EU targets are qualitatively discussed and quantitatively assessed with the simulation of a Reference and an alternative decarbonisation scenario to 2050. Simulations are carried out with the technology-rich PRIMES energy-system model and the GEM-E3 Computable General Equilibrium model. Restructuring of the EU energy system induces changes in the energy mix and production with small effects on the EU GDP, 0.4% in 2030 and 1% in 2050 compared to the Reference scenario. Energy efficiency improvements, increasing penetration of renewables, fuel switching towards natural gas, and technical progress in process related to emissions abatement are identified as essential options to the EU INDC implementation. The electrification of final energy demand, particularly transport electrification, complemented with decarbonised power supply is found to play a critical role in the successful transition towards a low-carbon economy by 2050.