Arnulf Grubler

• Managing Director at International Institute for Applied Systems Analysis

Developing transformative pathways for industry's compliance with international climate targets requires model-based insights into how supply- and demand-side measures affect industry, material cycles, global supply chains, socioeconomic activities, and service provisioning that support societal well-being. We review the recent literature modeling...

Conventional supply-side approaches overlook potential benefits

Buildings are key in supporting human activities and well-being by providing shelter and other important services to their users. Buildings are, however, also responsible for major energy use and greenhouse gas (GHG) emissions during their life cycle. Improving the quality of services provided by buildings while reaching low energy demand (LED) lev...

Chapter 5 (Demand, services and social aspects of mitigation), explores how mitigation interacts with meeting human needs and access to services. It explores, inter alia: sustainable production and consumption; patterns of development and indicators of wellbeing; the role of culture, social norms, practices and behaviour changes; the sharing econom...

Mitigation solutions are often evaluated in terms of costs and greenhouse gas reduction potentials, missing out on the consideration of direct effects on human well-being. Here, we systematically assess the mitigation potential of demand-side options categorized into avoid, shift and improve, and their human well-being links. We show that these opt...

Climate mitigation solutions are often evaluated in terms of their costs and potentials. This accounting, however, shortcuts a comprehensive evaluation of how climate solutions affect human well-being, which, at best, may only be crudely related to cost considerations. Here, we systematically list key sectoral mitigation options on the demand side,...

Technological knowledge can be created via R&D investments, but it can also be eroded through depreciation. Knowing how fast knowledge depreciates is important for various reasons for practitioners and decision makers alike; especially if it comes to questions regarding how to “recharge” knowledge production processes within an ever changing global...

Smaller, modular energy technologies have advantages

This report assesses all the positive potential benefits digitalization brings to sustainable development for all. It also highlights the potential negative impacts and challenges going forward, particularly for those impacted by the ‘digital divide’ that excludes primarily people left behind during the Industrial Revolution like the billion that g...

We present a global dataset of anthropogenic carbon dioxide (CO2) emissions for 343 cities. The dataset builds upon data from CDP (187 cities, few in developing countries), the Bonn Center for Local Climate Action and Reporting (73 cities, mainly in developing countries), and data collected by Peking University (83 cities in China). The CDP data be...

Scenarios that limit global warming to 1.5 °C describe major transformations in energy supply and ever-rising energy demand. Here, we provide a contrasting perspective by developing a narrative of future change based on observable trends that results in low energy demand. We describe and quantify changes in activity levels and energy intensity in t...

Research on climate change mitigation tends to focus on supply-side technology solutions. A better understanding of demand-side solutions is missing. We propose a transdisciplinary approach to identify demand-side climate solutions, investigate their mitigation potential, detail policy measures and assess their implications for well-being.

The demand for energy in buildings varies strongly across countries and climatic zones. These differences result from manifold factors, whose future evolution is uncertain. In order to assess buildings' energy demand across the 21st century, we develop an energy demand model — EDGE — and apply it in an analytical scenario framework — the shared soc...

Research on climate change mitigation tends to focus on supply-side technology solutions. A better understanding of demand-side solutions is missing. We propose a transdisciplinary approach to identify demand-side climate solutions, investigate their mitigation potential, detail policy measures, and assess their implications for well-being.

Benjamin Sovacool (2016) has provided interesting food for thought in asking “how long will it take?” for the unfolding of energy transitions. Historical evidence of “grand” or global energy system transitions taking decades to centuries to unfold contrasted with highly selective recent and rapid examples of mostly incremental technological change...

This study looks at the historical reliability of the agent-based model of the global energy system. We present a mathematical framework for the agent-based model calibration and sensitivity analysis based on historical observations. Simulation consistency with the historical record is measured as a distance between two vectors of data points and i...

Lovering et al. (2016) present data on the overnight costs of more than half of nuclear reactors built worldwide since the beginning of the nuclear age. The authors claim that this consolidated data set offers more accurate insights than previous country-level assessments. Unfortunately, the authors make analytical choices that mask nuclear power's...

To have a >50% chance of limiting warming below 2 °C, most recent scenarios from integrated assessment models (IAMs) require large-scale deployment of negative emissions technologies (NETs). These are technologies that result in the net removal of greenhouse gases from the atmosphere. We quantify potential global impacts of the different NETs on va...

Continuation of the U.S.’s historical pattern addressing energy problems only in times of crisis is unlikely to catalyze a transition to an energy system with fewer adverse social impacts. Instead, the U.S. needs to bolster support for energy innovation when the perceived urgency of energy‐related problems appears to be receding. Because of the lag...

Arnulf Grubler examines a study of power output and spatial area [mdash] a key concept in discussing renewables.

Uncertainty is a pervasive characteristic of all research addressed at the International Institute for Applied Systems Analysis (IIASA) which is at the core of this Special Issue. The role of science in better coping with uncertainty is twofold. First, to describe uncertainties as comprehensively and well as possible, both quantitatively and qualit...

Raising basic living standards and growing affluence aren’t equivalent, and neither are their respective climate impacts.

Professor Arnulf Grubler is a Senior Research Scholar and Acting Program Leader of the Transitions to New Technologies Program at the International Institute for Applied Systems Analysis (Laxenburg, Austria), as well as a Professor in the Field of Energy and Technology at the School of Forestry and Environmental Studies at Yale University (CT, USA)...

Climate change is a major externality justifying government-sponsored R&D efforts into climate-friendly technologies. Current and near-term R&D is needed to develop new and improve existing technological options that will be needed in the long-term future to drastically reduce greenhouse gas emissions. The paper contrasts historical and current gov...

The case study reviews a range of methodologies and model-based applications that can assist policy decisions under irreducible technology innovation uncertainties. One approach uses scenario analysis. A scenario study that explored a range of salient future uncertainties identified energy efficiency and conservation as the single most important an...

Energy technology innovation - improving how we produce and use energy - is critical for a transition towards sustainability. This book presents a rich set of twenty case studies of energy technology innovation embedded within a unifying conceptual framework. It provides insights into why some innovation efforts have been more successful than other...

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...

Mitigating climate change requires directed innovation efforts to develop and deploy energy technologies. Innovation activities are directed towards the outcome of climate protection by public institutions, policies and resources that in turn shape market behaviour. We analyse diverse indicators of activity throughout the innovation system to asses...

Urban systems now house about half of the world's population, but determine some three quarters of the global economy and its associated energy use and resulting environmental impacts. The twenty-first century will be increasingly urban. Sustainable development therefore needs first to be defined and analyzed, and then realized in urban settings. E...

This short essay first reviews the pioneers of energy transition research both in terms of data as well as theories. Three major insights that have emerged from this nascent research fields are summarized highlighting the importance of energy end-use and services, the lengthy process of transitions, as well as the patterns that characterize success...

This article reviews the concept of an energy technology innovation system (ETIS). The ETIS is a systemic perspective on innovation comprising all aspects of energy transformations (supply and demand); all stages of the technology development cycle; and all the major innovation processes, feedbacks, actors, institutions, and networks. We use it as...

More than 50% of the global population already lives in urban settlements and urban areas are projected to absorb almost all the global population growth to 2050, amounting to some additional three billion people. Over the next decades the increase in rural population in many developing countries will be overshadowed by population flows to cities....

More than 50% of the global population already lives in urban settlements and urban areas are projected to absorb almost all the global population growth to 2050, amounting to some additional three billion people. Over the next decades the increase in rural population in many developing countries will be overshadowed by population flows to cities....

Future scenarios of the energy system under greenhouse gas emission constraints depict dramatic growth in a range of energy technologies. Technological growth dynamics observed historically provide a useful comparator for these future trajectories. We find that historical time series data reveal a consistent relationship between how much a technolo...

The development and introduction of heat pumps provides an interesting illustration of policy influence and effectiveness in relation to energy technology innovation. Heat pumps have been supported by several countries since the 1970s as a strategy to improve energy efficiency, support energy security, reduce environmental degradation, and combat c...

This paper provides a synthesis of current knowledge on the patterns, drivers, and characteristics of historical energy technology transitions. This historical evidence is then compared to the treatment of energy system dynamics in the scenario analysis on climate mitigation. The paper concludes with a discussion of generic implications for clean e...

Synthesising the Case Studies. The twenty case studies examined in this volume cover a wide range of innovation histories for both energy supply and energy end-use technologies of markedly different characteristics and vintages. The market and policy contexts in which these innovation histories unfold also differ hugely. Yet as the editors’ guides...

Authors’ Summary. Technological knowledge, like all knowledge, can be learned or accumulated, but it can also be lost or "unlearned." In other words, knowledge capital depreciates. This case study considers the different sources of knowledge depreciation including reasons knowledge is lost (e.g., staff turnover) as well as why knowledge becomes obs...

Guidelines for Innovation Policy. Most of the case studies examined in this book explicitly discuss the role public policy has played in their respective innovation histories. The editors’ guides in each case study distil key lessons learnt for policies to support innovation systems. In this final chapter, these lessons are drawn together and summa...

A Systemic Perspective on Energy Technology Innovation. Throughout this book, we argue the case for a systemic perspective on energy technology innovation. We set out an analytical framework with all the key elements of the energy technology innovation system. We show how a wide range of historical innovation case studies all validate this innovati...

Author’s Summary. The case study reviews the French nuclear Pressurised Water Reactor (PWR) programme as an example of successful scaling up of a complex and capital-intensive energy technology. Starting in the early 1970s, France built fifty-eight PWRs with a total gross installed capacity of sixty-six GWe. On completion in the year 2000, they pro...

Author’s Summary. The case study reviews patterns, drivers, and dynamics (rates of change) in energy systems from a historical as well as futures (scenario) perspective. From a historical perspective, two major energy transitions, each of which took up to a century to unfold, can be identified: the phase of growth in coal-fired steam power, and its...

Authors’ Summary. Investments in end-use technologies are integral to energy system objectives including climate change mitigation. Across a wide range of future scenarios, reducing energy intensity by improving the efficiency of end-use technologies and supporting their widespread diffusion is a lower-cost and nearer-term complement to decarbonisi...

Authors’ Summary. This case study provides a quantitative overview of the financial resources mobilised globally as fundamental inputs into the energy technology innovation system. Available data from a diverse range of sources are compiled and summarised throughout the innovation life cycle from research and development (R$D) through market format...

Rationale for a Case Study Approach. Our evolving understanding of energy technology innovation and its systemic nature highlights the importance of contextual factors and the specific characteristics of technologies’ relative advantages, of influential actors and institutions, and of the public policies that support the mobilisation of resources....

Energy technology innovation – improving how we produce and use energy – is critical for a transition towards sustainability. This book presents a rich set of twenty historical case studies of energy technology innovation embedded within a unifying conceptual framework. It provides insights into why some innovation efforts have been more successful...

Authors’ Summary. Brazil’s Ethanol Program (ProAlcool), launched in 1975, was a direct response to the dramatic rise in imported petroleum prices in 1973. The military government of the time saw this as a challenge to Brazil’s financial stability and energy security, as the country imported 80 percent of the fuel used by its transport sector. Moreo...

The paper reviews the history and the economics of the French PWR program, which is arguably the most successful nuclear-scale up experience in an industrialized country. Key to this success was a unique institutional framework that allowed for centralized decision making, a high degree of standardization, and regulatory stability, epitomized by co...

Estimates of recent fossil fuel CO2 emissions have been compared with the IPCC SRES (Special Report on Emission Scenarios) emission scenarios that had been developed for analysis of future climate change, impacts and mitigation. In some cases this comparison uses averages across subgroups of SRES scenarios and for one category of greenhouse gases (...

Chakravarty et al. (1) have proposed an original burden-sharing scheme for global CO2 emission reduction efforts whose underlying theme of “Eat the Rich” (or as it turns out, rather, the middle-class) might resonate well in current times of economic crises. The core methodological elements of Chakravarty et al.'s proposal include the construction o...

Methane hydrates, ice-like compounds in which methane is held in crystalline cages formed by water molecules, are widespread in areas of permafrost such as the Arctic and in sediments on the continental margins. They are a potentially vast fossil fuel energy source but, at the same time, could be destabilized by changing pressure–temperature condit...

Capturing the main interactions within the energy system through an integrated modelling framework, salient uncertainties of the future of fossil extractive industries are explored through a scenario approach. The results are summarised and then further analysed through further scenario/model sensitivity runs to highlight the influence of major pol...

This paper presents a stylized model of technology adoptions for sustainable development under the three potentially most important "stylized facts": increasing returns to adoption, uncertainty, and heterogeneous agents following diverse technology development and adoption strategies. The stylized model deals with three technologies and two heterog...

An important question for climate policy making is how much GHG emissions and energy can be saved, in which sectors and at what costs? Traditionally, studies looking at this question are often characterised as either using a Bottom-Up or a Top-Down approach. The differences between these approaches are far from clear-cut. The first approach tends t...

This paper provides the background and the context for the analyses presented in the seven papers of this Special Issue on Integrated Assessment of Uncertainties in Greenhouse Gas Emissions and their Mitigation. First, the main topic and content of the Special Issue is given, followed by an overall overview. Second, detailed overviews and summaries...

This paper presents an overview of the greenhouse gas (GHG) emissions scenarios that form the analytical backbone for other contributions to this Special Issue. We first describe the motivation behind this scenario exercise and introduce the main scenario features and characteristics, in both qualitative and quantitative terms. Altogether, we analy...

We report here spatially explicit scenario interpretations for population and economic activity (GDP) for the time period 1990 to 2100 based on three scenarios (A2, B1, and B2) from the IPCC Special Report on Emissions Scenarios (SRES). At the highest degree of spatial detail, the scenario indicators are calculated at a 0.5 by 0.5 degree resolution...

The more the world advances technologically, the more people realize that such progress has real costs, including dwindling material resources and the proliferation of wastes. The key to sustainable development is in productivity growth: engineering new solutions to reduce the environmental costs of human success.

Learning - i.e. the acquisition of new information that leads to changes in our assessment of uncertainty plays a prominent role in the international climate policy debate. For example, the view that we should postpone actions until we know more continues to be influential. The latest work on learning and climate change includes new theoretical mod...

This note is a final response to the debate raised by Mr. Castles and Mr. Henderson (for brevity, we refer here to the two authors simply as C&H) in this Journal ( vol 14, no 2&3, and no 4) on the issue of economic growth in developing countries in some of the emissions scenarios published in the IPCC Special Report on Emissions Scenarios (SRES) (N...

Technology and Global Change describes how technology has shaped society and the environment over the last 200 years. Technology has led us from the farm to the factory to the internet, and its impacts are now global. Technology has eliminated many problems, but has added many others (ranging from urban smog to the ozone hole to global warming). Th...

We agree with M.I. Hoffert et al. (Advanced technology paths to global climate stability: Energy for a greenhouse planet, Review, 1 Nov., p. 981) that stabilizing atmospheric CO2 concentrations at 550 parts per million (ppm) or below will require investment in energy research and development well in excess of current levels. However, their that kno...

We need to research all the potential outcomes, not try to guess which is likeliest to occur.

This communication summarizes the main findings of INASUD, an Europeanwide research project on integrated assessment of climate policies. The project aimed at improving the framing of climate policy analysis through the parallel use of various existing integrated assessment models. It provides a comprehensive examination of the link between uncerta...

Time-dependent geographical distributions of surface-air temperature change relative to year 2000 are constructed for four scenarios of greenhouse gas (GHG) and sulfur dioxide (SO2) emissions, and are compared to the IS92a scenario. The four new scenarios have been developed by four different modeling teams. The four scenarios are noninterventionis...

The conference was stimulated by concern that policy makers increasingly have to make environmental management decisions in the absence of solidly established scientific consensus about ecological processes and the consequences of human actions. Often, as in the case of climate change, some decisions may have to be made in the absence of informatio...

This study explores the concept of new energy infrastructures (in particular gas pipelines) in Eurasia and discusses its implications on future energy systems, gas trade, and the environment. Overall resource availability is not expected to be a real constraint in meeting growing energy demand within the next 100 years, but the geographical concent...

The GIS approach presented links night satellite imagery data of visible, near-infrared light with other spatially explicit data on topography, infrastructure availability and well as demographics. These data set are used in a stochastic gravity model of spatial interactions to simulate geographic patterns of growth in nocturnal lighting. The simul...

The essay reviews major environmental problems of energy development within a broader development and sustainability context. The role of energy in human development and major historical trends as well as their implications for carbon dioxide emissions are discussed. After summarising the scientific understanding of current and possible future clim...

In 1992 the IPCC released emission scenarios to be used for driving global circulation models to develop climate change scenarios. The so-called IS92 scenarios were path breaking. They were the first global scenarios to provide estimates for the full suite of greenhouse gases. Much has changed since then in our understanding of possible future gree...

Abstract Technology largely determines economic development and its impact on the environment; yet technological change is one of the least developed parts of existing global change models. This paper reviews two approaches developed at the International Institute for Applied Systems Analysis, both of which use the concept of technological learning...

Technological choices largely determine the long-term characteristics of industrial society, including impacts on the natural environment. However, the treatment of technology in existing models that are used to project economic and environmental futures remains highly stylized. Based on work over two decades at IIASA, we present a useful typology...

The paper reviews base year emission inventories, driving forces, and long-term scenarios of sulfur emissions as background material for developing a new set of IPCC emissions scenarios. The paper concludes that future sulfur emission trends will be spatially heterogeneous (decline in OECD countries, rapid increase particularly in Asia) and therefo...

Global energy needs are expanding substantially as populations grow and economies develop around the world. There is clear evidence that continued use of fossil fuels as the world's dominant energy supply is damaging the environment and causing changes in global climate patterns. People want higher levels of more efficient, cleaner, and less obtrus...