South East Europe electricity roadmap – modelling energy transition in the electricity sectors

One of the most important challenges for the South East Europe region will be replacing more than 30% of its presently installed fossil fuel generation capacity by the end of 2030, and more than 95% by 2050 if its age structure is considered. This requires a strong policy framework to incentivise new investments in a region currently lacking investors, but also presents an opportunity to shape the electricity sector over the long term according to the broader energy transition strategy of the EU and the Energy Community. The aim of this paper is to assess what type of long-term pathways exist for electricity sector development in the region if they follow the energy transition process of the EU. In this model-based scenario assessment, long term electricity sector futures are explored using a set of interlinked electricity models evaluating the level of renewable energy investment required in the region to reach a deep decarbonization target, assuming emission reduction above 94% by 2050 compared to 1990 in line with the long term market integration and climate policy goals of the EU. It also explores what are the most important system wide impacts of the high deployment of renewable energy concerning generation adequacy and security of supply.

Key policy insights

• Energy policies in the South East Europe (SEE) region, both at the national and regional level, should focus on enabling renewable energy integration, as this will be a key component of the future energy mix.

• EU and Energy Community policies should be incorporated into national energy planning to ensure that SEE countries embark on the energy transition process at an early stage.

• Stranded costs should be carefully considered in decision-making on new fossil-fuel generation and gas network investment in order to avoid lock-in to carbon intensive technologies.

• If consistent decarbonization policy prevails, with a significant and persistent CO2 price signal, the role of natural gas remains transitory in the region.

• The SEE region offers relatively cheap decarbonization options: the power sector can reduce GHG emissions above 94% by 2050 in the modelled scenarios.

     

Potential Scale-Related Problems in Estimating the Costs of CO2 Mitigation Policies

The scale-related problem addressed here relates to a difficulty in substituting away from fossil fuels as part of a policy designed to mitigate climate change. The replacement of fossil fuels by renewable forms of energy is a widely advocated means of reducing the build-up greenhouse gases in the atmosphere. However, the substitution, on a large-scale, of renewable, non-fossil fuel energy sources for fossil fuels requires using vast amounts of land to produce energy. It is shown that, with the exception of nuclear energy, almost all non-fossil fuel energy sources are highly land using, or land-intensive. In particular, the widespread substitution of renewables such as biomasses, wind, solar, and hydro for fossil fuels would require adapting large amounts of land to energy production, land which may have good alternative uses. Thus, the economic feasibility of producing, globally, relatively small amounts of renewable energies is not a good indicator of the feasibility of producing them on a large scale. This implies that substantial reduction in the use of fossil fuels requires the discovery and development of new non-land intensive energy technologies.     

Implications of Japan’s long term climate mitigation target and the relevance of uncertain nuclear policy

Achieving long-term climate mitigation goals in Japan faces several challenges, starting with the uncertain nuclear power policy after the 2011 earthquake, the uncertain availability and progress of energy technologies, as well as energy security concerns in light of a high dependency on fuel imports. The combined weight of these challenges needs to be clarified in terms of the energy system and macroeconomic impacts. We applied a general equilibrium energy economic model to assess these impacts on an 80% emission reduction target by 2050 considering several alternative scenarios for nuclear power deployment, technology availability, end use energy efficiency, and the price of fossil fuels. We found that achieving the mitigation target was feasible for all scenarios, with considerable reductions in total energy consumption (39%–50%), higher shares of low-carbon sources (43%–72% compared to 15%), and larger shares of electricity in the final energy supply (51%–58% compared to 42%). The economic impacts of limiting nuclear power by 2050 (3.5% GDP loss) were small compared to the lack of carbon capture and storage (CCS) (6.4% GDP loss). Mitigation scenarios led to an improvement in energy security indicators (trade dependency and diversity of primary energy sources) even in the absence of nuclear power. Moreover, preliminary analysis indicates that expanding the range of renewable energy resources can lower the macroeconomic impacts of the long term target considerably, and thus further in depth analysis is needed on this aspect.

Key policy insights

• For Japan, an emissions reduction target of 80% by 2050 is feasible without nuclear power or CCS.

• The macroeconomic impact of such a 2050 target was largest without CCS, and smallest without nuclear power.

• Energy security indicators improved in mitigation scenarios compared to the baseline.

     

Exploring national decarbonization pathways and global energy trade flows: a multi-scale analysis

The role of fossils fuels in national economies will change radically over the next 40 years under a strong climate regime. However, capturing this changing role through national-based analyses is challenging due to the global nature of fossil fuel demand and resulting trade patterns. This article sets out the limitations of existing national-scale decarbonization analyses in adequately capturing global conditions and explores how the introduction of a global modelling framework could provide vital insights, particularly for those countries that are dependent on fossil fuel exports or imports.

The article shows that fossil fuel use will significantly decline by 2050, although gas will have an important transition role. This leaves large fossil fuel exporters exposed, the extent of which is determined by mitigation action in different regions and especially by the pathways adopted by the larger Asian economies. We find that global-scale models provide critical insights that complement the more detailed national analyses and should play a stronger role in informing deep decarbonization pathways (DDPs). They also provide an important basis for exploring key uncertainties around technology uptake, mitigation rates and how this plays out in the demand for fossil fuels. However, use of global models also calls for improved representation of country specifics in global models, which can oversimplify national economic and political realities. Using both model scales provides important insights that are complementary but that can challenge the other’s orthodoxy. However, neither can replace the other’s strengths.

Policy relevance:

In recent years, how global fossil fuel markets will evolve under different climate regimes has been subject to much debate and analysis. This debate includes whether investments in fossil fuel production still make sense or will be exposed in the future to liabilities associated with high carbon prices. This is important for governments who need to develop coherent policy in relation to fossil fuel sectors and their role as drivers of economic growth and in providing for domestic energy needs. This article argues that national analyses need to be fully cognizant of the global-scale transition, which can be informed by using a multi-scale modelling approach.     

Global implications of joint fossil fuel subsidy reform and nuclear phase-out: an economic analysis

This paper uses the OECD’s global recursive-dynamic general equilibrium model ENVLinkages to examine the mid-term economic consequences and the optimal energy supply mix adjustments of a simultaneous implementation of i) a progressive fossil fuel subsidy reform in emerging and developing economies and ii) a progressive phase out of nuclear energy, mostly affecting OECD countries, China and Russia. The analysis is then transposed in the context of climate change mitigation to depict the corresponding implications for CO2 emissions, to assess the interactions between the two energy policies, and to derive how the associated costs are affected by the different policies. The phase-out scenario projects a nuclear capacity halved by 2035 as compared to the Baseline, corresponding to $120 billion losses in value-added of the nuclear industry for that year. The nuclear phase-out leaves GDP and real household consumption marginally affected in energy importing countries. A multilateral subsidy reform is more likely to affect international fossil fuel prices and alter patterns of global energy use. The fossil fuel subsidy reform, when implemented together with nuclear phase-out, more than offsets negative consequences on household consumption but still leads to a decrease in global CO2 emissions. The combined policies help save the equivalent of current energy consumption in the Middle East. Combining a climate policy, an effective fossil fuel subsidy reform, even with a lower nuclear share in the power mix, brings about multiple benefits to OECD countries which reduce their energy bill and achieve large climate change mitigation at lower cost.     

Being green or being nice? People are more likely to share nicer but potentially less impactful green messages

As the world’s largest fossil fuels exporter, Russia is one of the key countries for addressing global climate change. However, it has never demonstrated any significant ambitions to reduce greenhouse gas (GHG) emissions. This paper applies ideational research methodology to identify the structural differences in economic, political, and social normative contexts between industrialized fossil fuel importing economies and Russia that lead to the fundamental gap in motivations driving decarbonization efforts. Russia is unlikely to replicate the approach to the green transition and climate policy instruments of energy-importing countries. In order to launch decarbonization in Russia, interested stakeholders need to frame climate policies in Russia differently. Specifically, the framing must address the priority of diversification as a means to adapting the national economy to a new green landscape, the combination of diverse channels for decarbonization, the promotion of energy-efficiency, closer attention to climate-related forest projects, and linkage of climate change with other environmental problems. Moreover, considering Russia’s emissions as a part of the global economic system and shifting from a simplistic national focus on GHG emissions reduction would help coordinate policies through dialogue between exporters and importers of fossil fuel energy-intensive goods, which is essential for the global movement towards a net-zero future.

     

Would constraining US fossil fuel production affect global CO<Subscript>2</Subscript> emissions? A case study of US leasing policy

Avoiding dangerous climate change will require a rapid transition away from fossil fuels. By some estimates, global consumption and production of fossil fuels—particularly coal and oil—will need to end almost entirely within 50 years. Given the scale of such a transition, nations may need to consider policies that constrain growth in fossil fuel supplies in addition to those that reduce demand. Here, we examine the emissions implications of a supply-constraining measure that was rapidly gaining momentum in the United States (US) under the Obama administration: ceasing the issuance of new leases for fossil fuel extraction on federal lands and waters. Such a measure could reduce global carbon dioxide emissions by an estimated 280 million tons annually by 2030, comparable to that of other major climate policies adopted or considered by the Obama administration. Our findings suggest that measures to constrain fossil fuel supply—though not currently viable in a US Trump administration—deserve further consideration at subnational levels in the US or by other countries now, and by future US administrations.     

Developing Africa’s energy mix

Africa is growing rapidly both in terms of population size and economically. It is also becoming increasingly clear that fossil fuels impose a high price on society through local environmental pollution and Africa’s particular vulnerability to climate change. At the same time, Africa has an excellent renewable energy potential and prices for renewable energy are reaching the price range of fossil fuels. Comparing results from state-of-the-art Integrated Assessment Models we find different options for achieving a sustainable energy supply in Africa. They have in common, however, that strong economic development is considered compatible with the 2°C climate target. Taking both challenges and appropriate solutions into account, some models find that a complete switch to renewable energy in electricity production is possible in the medium term. The continental analysis identifies important synergy effects, in particular the exchange of electricity between neighbouring countries. The optimal energy mix varies considerably between African countries, but there is sufficient renewable energy for each country. The intermittency and higher capital intensity of renewable energy are important challenges, but proven solutions are available for them. In addition, we analyse the political economy of a sustainable energy transition in Africa.

Key policy insights

• An almost complete shift towards renewable energy (RE) is considered feasible and affordable in Africa.

• By 2050, electricity generation could be sourced largely from solar, wind and hydro power.

• Prices for RE in Africa are now within the price range of fossil fuels, partly due to the excellent RE potential.

• The optimal energy mix varies strongly between countries, but RE is sufficiently available everywhere.

• Addressing intermittency is possible, but requires investments and cooperation on the grid.

     

The Chinese Carbon-Neutral Goal: Challenges and Prospects

On 22 September 2020, within the backdrop of the COVID-19 global pandemic, China announced its climate goal for peak carbon emissions before 2030 and to reach carbon neutrality before 2060. This carbon-neutral goal is generally considered to cover all anthropogenic greenhouse gases. The planning effort is now in full swing in China, but the pathway to decarbonization is unclear. The needed transition towards non-fossil fuel energy and its impact on China and the world may be more profound than its reform and development over the past 40 years, but the challenges are enormous. Analysis of four representative scenarios shows significant differences in achieving the carbon-neutral goal, particularly the contribution of non-fossil fuel energy sources. The high target values for nuclear, wind, and bioenergy have approached their corresponding resource limitations, with solar energy being the exception, suggesting solar’s critical role. We also found that the near-term policies that allow for a gradual transition, followed by more drastic changes after 2030, can eventually reach the carbon-neutral goal and lead to less of a reduction in cumulative emissions, thus inconsistent with the IPCC 1.5°C scenario. The challenges and prospects are discussed in the historical context of China’s socio-economic reform, globalization, international collaboration, and development.     

Renewable energy policies and household solid fuel dependence

What effects do domestic and international policies have on household solid fuel consumption? Previous studies analyze some of the policies that national governments and international organizations have implemented to reduce solid fuel dependence, but these studies tend to examine one policy and/or one country at a time. In contrast, this article seeks to provide a more systematic analysis of whether and to what extent domestic and international policies can encourage transition to less polluting fuels. Using data on the proportion of population using solid cooking fuels, and domestic and international programs promoting renewable energy, we evaluate the association between renewable energy policies and household solid fuel dependence. Our statistical tests show that such policies, regardless of their domestic or international origins, matter in explaining the level of solid fuel dependence. As the number of domestic policies increases, the share of population using solid fuels tends to decline. International efforts to promote renewable energy are also linked to reduced solid fuel dependence in countries where such international programs are implemented.     

The threat to climate change mitigation posed by the abundance of fossil fuels

This article analyses the trends in primary demand for fossil fuels and renewables, comparing regions with large and small domestic fossil fuel reserves. We focus on countries that hold 80% of global fossil fuel reserves and compare them with key countries that have meagre fossil fuel reserves. We show that those countries with large domestic fossil fuel reserves have experienced a large increase in primary energy demand from fossil fuels, but only a moderate or no increase in primary energy from renewables, and in particular from non-hydro renewable energy sources (NHRES), which are assumed to represent the cornerstone of the future transformation of the global energy system. This implies a tremendous threat to climate change mitigation, with only two principal mitigation options for fossil-fuel-rich economies if there is to be compliance with the temperature goals of the Paris Agreement: (1) leave the fossil fuels in the ground; and (2) apply carbon capture and storage (CCS) technologies. Combinations of these two options to exploit their respective possibilities synergistically will require strong initiatives and incentives to transform a certain amount of the domestic fossil fuel reserves (including the associated infrastructure) into stranded assets and to create an extensive CCS infrastructure. Our conclusion is that immediate and disruptive changes to the use of fossil fuels and investments in non-carbon-emitting technologies are required if global warming is to be limited to well below 2°C. Collective actions along value chains in business to divert from fossil fuels may be a feasible strategy.

Key policy insights

• The main obstacle to compliance with any reasonable warming target is the abundance of fossil fuels, which has maintained and increased momentum towards new fossil-fuelled processes.

• So far, there has been no increase in the share of NHRES in total global primary energy demand, with a clear decline in the NHRES share in India and China.

• There is an immediate need for the global community to develop fossil fuel strategies and policies.

• Policies must account for the global trade flow of products that typically occurs from the newly industrialized fossil fuel-rich countries to the developed countries.

     

Decarbonization and regulation of Germany's electricity system after Fukushima

Germany's current efforts to decarbonize its electricity system are analysed. As nuclear power and fossil power plants equipped with carbon capture and storage were ruled out in 2011, renewable electricity generation (RES) together with electricity savings are the primary focus for achieving decarbonization. Germany aims to have RES account for at least 80% of its electricity by 2050. Achieving renewable generation needs strong political support and regulatory provisions for its market integration. Four main technical and regulatory challenges are the maintenance of a steady and efficient expansion of RES, the provision of balancing capacities, the realization of the targeted electricity savings, and the smart adaptation of the transport and distribution grid. An overview of the existing and planned regulatory provisions for decarbonization are described, and some gaps identified, particularly with regard to the overall management of the process, the inclusion of electricity savings and the interference of Germany's decarbonization strategies with neighbouring countries. Policies that both accelerate grid expansion and direct RES expansion should immediately be put in place and can be supported by a targeted mobilization of balancing capacities. Electricity savings are a significant and cost-efficient strategy for low-carbon electricity.

Policy relevance

Germany is actively converting its national electricity system towards a fully renewable one. As renewable electricity has reached about a quarter of total consumption, a number of technical and regulatory challenges arise. Current discussions and plans are described for the four main challenges: maintaining and optimizing high investment rates into RES generation technologies, providing balancing capacities, reducing demand, and adapting the grid to the changing needs. Policy recommendations for these four tasks highlight the need to intensify electricity demand reduction and also consider the potential interactions between the German electricity system and its neighbouring countries.     

Renewable and low-carbon energies as mitigation options of climate change for China

This article discusses how renewable and low-carbon energies can serve as mitigation options of climate change in China’s power sector. Our study is based on scenarios developed in PowerPlan, a bottom-up model simulating a countries’ power sector and its emissions. We first adjusted the model to China’s present-day economy and power sector. We then developed different scenarios based on story lines for possible future developments in China. We simulated China’s carbon-based electricity production system of today and possible future transitions towards a low-carbon system relying on renewable and low-carbon energies. In our analysis, we compare the business-as-usual scenarios with more sustainable energy scenarios. We found that by increasing the share of renewable and nuclear energies to different levels, between 17% and 57% of all CO₂ emissions from the power sector could be avoided by 2030 compared to the business-as-usual scenario. We also found that electricity generation costs increase when more sustainable power plants are installed. As a conclusion, China has two options: choosing for high climate change mitigation and high costs or choosing for moderate climate change mitigation and moderate costs. In case high climate change mitigation will be chosen, development assistance is likely to be needed to cover the costs.     

Causal thinking and support for climate change policies: International survey findings

Few comparative international studies describe the climate change policies people are willing to support and the reasons for their support of different policies. Using survey data from 664 economics and business undergraduates in Austria, Bangladesh, Finland, Germany, Norway, and the United States, we explore how perceived risk characteristics and mental models of climate change influence support for policy alternatives. General green policies such as funding research on renewable technologies and planting trees were the overwhelmingly most popular policy alternatives. Around half the students support carbon reduction policies such as requiring higher car fuel efficiency and increasing taxes on fossil fuels. Least popular were engineering alternatives such as fertilizing the oceans and replacing fossil fuels with nuclear power. Variations among nations are generally small. Support for different policy alternatives corresponds with different causal thinking. Those who hold a pollution model of the causes of climate change, tend to blame environmental harms (e.g., air pollution from toxic chemicals), see general green policy alternatives as effective, and support general green policies. Support of carbon reduction strategies is associated with seeing carbon emissions as the cause and reducing carbon emissions as effective solutions. Support of engineering solutions increases with identifying volcanoes among causes and regarding engineering solutions as effective. Although these international students agree that climate change is a threatening problem, their causal thinking correlates with support for different mitigative policy actions, with the most popular ones not necessarily the most effective.     

Fossil fuel addiction and the implications for climate change policy

This paper applies a behavioral economics model of cigarette addiction to the issue of fossil fuel usage and climate change. Both problems involve consumption of a currently beneficial product that causes detrimental effects in the distant future and for which current reductions in usage induces an adjustment cost. The paper argues that because fossil fuel control requires solving an international public goods problem as well as an addiction-like problem, breaking it will be more challenging. Using insights from the model, it also suggests that fossil fuel addiction, like cigarette addiction, may generate a long period of time in which people express sincere desire to convert to clean energy, but accomplish little to achieve that outcome. Finally the paper examines the history of the international anti-smoking campaign to draw insights for the campaign against global climate change. The analogy suggests that policies to reduce the present cost of non-carbon energy sources to induce voluntary adjustments in energy usage, or, policies that induce cleaner usage of fossil fuels, or geo-engineering policies that work to reverse the warming effects of higher CO₂ concentrations, may be more viable than policies that raise the cost of current fossil fuel consumption.     

Climate policies after Fukushima: three views

The 2011 Japanese earthquake and tsunami, and the consequent accident at the Fukushima nuclear power plant, have had consequences far beyond Japan itself. Reactions to the accident in three major economies Japan, the UK, and Germany, all of whom were committed to relatively ambitious climate change targets prior to the accident are examined. In Japan and Germany, the accident precipitated a major change of policy direction. In the UK, debate has been muted and there has been essentially no change in energy or climate change policies. The status of the energy and climate change policies in each country prior to the accident is assessed, the responses to the accident are described, and the possible impacts on their positions in the international climate negotiations are analysed. Finally, the three countries' responses are compared and some differences between them observed. Some reasons for their different policy responses are suggested and some themes, common across all countries, are identified

Policy relevance

The attraction of nuclear power has rested on the promise of low-cost electricity, low-carbon energy supply, and enhanced energy independence. The Fukushima accident, which followed the Japanese tsunami of March 2011, has prompted a critical re-appraisal of nuclear power. The responses to Fukushima are assessed for the UK, Germany, and Japan. Before the accident, all three countries considered nuclear as playing a significant part in climate mitigation strategies. Although the UK Government has continued to support nuclear new build following a prompt review of safety arrangements, Japan and Germany have decided to phase out nuclear power, albeit according to different timescales. The factors that explain the different decisions are examined, including patterns of energy demand and supply, the wider political context, institutional arrangements, and public attitudes to risk. The implications for the international climate negotiations are also assessed.     

Cutting with both arms of the scissors: the economic and political case for restrictive supply-side climate policies

Proponents of climate change mitigation face difficult choices about which types of policy instrument(s) to pursue. The literature on the comparative evaluation of climate policy instruments has focused overwhelmingly on economic analyses of instruments aimed at restricting demand for greenhouse gas emissions (especially carbon taxes and cap-and-trade schemes) and, to some extent, on instruments that support the supply of or demand for substitutes for emissions-intensive goods, such as renewable energy. Evaluation of instruments aimed at restricting the upstream supply of commodities or products whose downstream consumption causes greenhouse gas emissions—such as fossil fuels—has largely been neglected in this literature. Moreover, analyses that compare policy instruments using both economic and political (e.g. political “feasibility” and “feedback”) criteria are rare. This article aims to help bridge both of these gaps. Specifically, the article demonstrates that restrictive supply-side policy instruments (targeting fossil fuels) have numerous characteristic economic and political advantages over otherwise similar restrictive demand-side instruments (targeting greenhouse gases). Economic advantages include low administrative and transaction costs, higher abatement certainty (due to the relative ease of monitoring, reporting and verification), comprehensive within-sector coverage, some advantageous price/efficiency effects, the mitigation of infrastructure “lock-in” risks, and mitigation of the “green paradox”. Political advantages include the superior potential to mobilise public support for supply-side policies, the conduciveness of supply-side policies to international policy cooperation, and the potential to bring different segments of the fossil fuel industry into a coalition supportive of such policies. In light of these attributes, restrictive supply-side policies squarely belong in the climate policy “toolkit”.     

Challenges for hydropower-based nationally determined contributions: a case study for Ecuador

Hydropower is the dominant renewable energy source to date, providing over two-thirds of all renewable electricity globally. For countries with significant hydropower potential, the technology is expected to play a major role in the energy transition needed to meet nationally determined contributions (NDCs) for greenhouse gas (GHG) emission reductions as laid out in the Paris Agreement. For the Republic of Ecuador, large hydropower is currently considered as the main means for attaining energy security, reducing electricity prices and mitigating GHG emissions in the long-term. However, uncertainty around the impacts of climate change, investment cost overruns and restrictions to untapped resources may challenge the future deployment of hydropower and consequently impact decarbonization efforts for Ecuador’s power sector. To address these questions, a partial equilibrium energy system optimization model for Ecuador (TIMES-EC) is used to simulate alternative electricity capacity expansion scenarios up to 2050. Results show that the share of total electricity supplied by hydropower in Ecuador might vary significantly between 53% to 81% by 2050. Restricting large hydropower due to social-environmental constraints can cause a fourfold increase in cumulative emissions compared to NDC implied levels, while a 25% reduction of hydropower availability due to climate change would cause cumulative emissions to double. In comparison, a more diversified power system (although more expensive) which limits the share of large hydropower and natural gas in favour of other renewables could achieve the expected NDC emission levels. These insights underscore the critical importance of undertaking detailed whole energy system analyses to assess the long-term challenges for hydropower deployment and the trade-offs among power system configuration, system costs and expected GHG emissions in hydropower-dependent countries, states and territories.

Key policy insights

• Ecuador’s hydropower-based NDC is highly vulnerable to the occurrence of a dry climate scenario and restrictions to deployment of large hydropower in the Amazon region.

• Given Ecuador’s seasonal runoff pattern, fossil-fuel or renewable thermoelectric backup will always be required, whatever the amount of hydropower installed.

• Ecuador’s NDC target for the power sector is achievable without the deployment of large hydropower infrastructure, through a more diversified portfolio with non-hydro renewables.

     

Bioenergy in energy transformation and climate management

This study explores the importance of bioenergy to potential future energy transformation and climate change management. Using a large inter-model comparison of 15 models, we comprehensively characterize and analyze future dependence on, and the value of, bioenergy in achieving potential long-run climate objectives. Model scenarios project, by 2050, bioenergy growth of 1 to 10 % per annum reaching 1 to 35 % of global primary energy, and by 2100, bioenergy becoming 10 to 50 % of global primary energy. Non-OECD regions are projected to be the dominant suppliers of biomass, as well as consumers, with up to 35 % of regional electricity from biopower by 2050, and up to 70 % of regional liquid fuels from biofuels by 2050. Bioenergy is found to be valuable to many models with significant implications for mitigation and macroeconomic costs of climate policies. The availability of bioenergy, in particular biomass with carbon dioxide capture and storage (BECCS), notably affects the cost-effective global emissions trajectory for climate management by accommodating prolonged near-term use of fossil fuels, but with potential implications for climate outcomes. Finally, we find that models cost-effectively trade-off land carbon and nitrous oxide emissions for the long-run climate change management benefits of bioenergy. The results suggest opportunities, but also imply challenges. Overall, further evaluation of the viability of large-scale global bioenergy is merited.     

Climate policies can help resolve energy security and air pollution challenges

This paper assesses three key energy sustainability objectives: energy security improvement, climate change mitigation, and the reduction of air pollution and its human health impacts. We explain how the common practice of narrowly focusing on singular issues ignores potentially enormous synergies, highlighting the need for a paradigm shift toward more holistic policy approaches. Our analysis of a large ensemble of alternate energy-climate futures, developed using MESSAGE, an integrated assessment model, shows that stringent climate change policy offers a strategic entry point along the path to energy sustainability in several dimensions. Concerted decarbonization efforts can lead to improved air quality, thereby reducing energy-related health impacts worldwide: upwards of 2–32 million fewer disability-adjusted life years in 2030, depending on the aggressiveness of the air pollution policies foreseen in the baseline. At the same time, low-carbon technologies and energy-efficiency improvements can help to further the energy security goals of individual countries and regions by promoting a more dependable, resilient, and diversified energy portfolio. The cost savings of these climate policy synergies are potentially enormous: $100–600 billion annually by 2030 in reduced pollution control and energy security expenditures (0.1–0.7 % of GDP). Novel aspects of this paper include an explicit quantification of the health-related co-benefits of present and future air pollution control policies; an analysis of how future constraints on regional trade could influence energy security; a detailed assessment of energy expenditures showing where financing needs to flow in order to achieve the multiple energy sustainability objectives; and a quantification of the relationships between different fulfillment levels for energy security and air pollution goals and the probability of reaching the 2 °C climate target.