• Energy Research

While national climate policy can address countries’ production or consumption, climate mitigation via changes in consumption has previously received relatively little attention in climate policy literature. In the absence of an effective international climate policy, the focus on consumption is gaining relevance since it has advantages regarding carbon leakage and competitiveness concerns. In addition, consumption oriented climate policy allows for low cost climate mitigation because of behavioral market failures. Therefore, a systematic evaluation of low greenhouse gas consumption options is needed. This article reviews the carbon footprint of products in the five main consumption categories (food, shelter, travel, goods and service) and compares their compatibility with the greenhouse gas intensity required in 2050 to meet the 2° climate target. The evaluation then identifies consumption options compatible with this climate target in all categories. The description of these consumption options allows for the recognition of barriers to their selection. In contrast to production oriented climate policy, besides costs, relevant barriers include consumer preferences, the skills required to find or adopt the product and high initial investments. We conclude that there is substantial climate mitigation potential from changing consumption choices which can be tapped through climate policy by addressing non-cost barriers.

The past few years have seen the emergence of several global multiregional input–output (MRIO) databases. Due to the cost and complexity of developing such extensive tables, industry sectors are generally represented at a rather aggregate level. Currently, one of the most important applications of input–output analysis is environmental assessments, for which highly aggregate sectors may not be sufficient to yield accurate results. We experiment with four of the most important global MRIO systems available, analyzing the sensitivity of a set of aggregate CO2 multipliers to aggregations in the MRIO tables used to calculate them. Across databases, we find (a) significant sensitivity to background system detail and (b) that sub-sectors contained within the same aggregate MRIO sector may exhibit highly different carbon multipliers. We conclude that the additional information provided by the extra sector detail may warrant the additional costs of compilation, due to the heterogeneous nature of economic sectors ...

Abstract Energy systems are major contributors to critical environmental problems including climate change and air pollution. Over half of global energy end use is in the form of heat, three-quarters of which is from fossil fuels. We assess different ways to provide heat, cooling, and electricity to a university campus, comparing lifecycle primary energy requirements, greenhouse gas (GHG) emissions, and particulate matter impacts. For this case study, replacing cogeneration of cooling, heat, and power with grid electricity and building level heating and cooling can reduce GHG emissions by 30%, while cogeneration of heating and cooling in an electrically powered heat recovery chiller system with thermal energy storage can reduce GHG emissions by 45%. GHG reductions from grid electricity remain even if it is assumed to come from more carbon intensive marginal electricity generation. Prominent factors affecting the environmental benefits of polygeneration are identified, most notably the fuel mix and energy efficiency of regional grid electricity, and combined heat and power system efficiency. Thermal energy storage adds resilience to the system while reducing environmental impacts. A heuristic charts the viability of combined versus separate heat and power production for a general case, based on cogeneration efficiency and regional electricity carbon intensity. Low carbon grid electricity strengthens the case for a shift in polygeneration systems from combined heat and power to combined heating and cooling.

Abstract False narratives cloud our understanding of Europe’s energy crisis and its relationship to climate change and climate policy. A clear-eyed understanding, based on factual knowledge and the insights of scientific research can help resolve the seeming contradiction between security of supply, affordability, and environmental sustainability.

Abstract The decarbonization of the transport sector requires a rapid expansion of global battery production and an adequate supply with raw materials currently produced in small volumes. We investigate whether battery production can be a bottleneck in the expansion of electric vehicles and specify the investment in capital and skills required to manage the transition. This may require a battery production rate in the range of 4–12 TWh/year, which entails the use of 19–50 Mt/year of materials. Strengthening the battery value chain requires a global effort in many sectors of the economy that will need to grow according to the battery demand, to avoid bottlenecks along the supply chains. Significant investment for the establishment of production facilities (150–300 billion USD in the next 30 years) and the employment of a large global workforce (400k–1 million) with specific knowledge and skillset are essential. However, the employment and investment required are uncertain given the relatively early development stage of the sector, the continuous advancements in the technology and the wide range of possible future demand. Finally, the deployment of novel battery technologies that are still in the development stage could reduce the demand for critical raw materials and require the partial or total redesign of production and recycling facilities affecting the investment needed for each factory.

A flowsheet for the production of the substitutable transportation fuel dimethyl ether through biomass steam gasification to fuel (BSGtF) was constructed including heat integration. A quasi-equilibrium model was applied to simulate the whole process based on rigorous thermodynamic property prediction models. The carbon and hydrogen flows of the process showed that the atom utilization efficiency of carbon from the biomass to fuel process was 38.47%, and 39.75% of the total hydrogen was converted to the fuel product. The exergy flows of the total process and the exergy loss taking place in each process section were calculated based on the second law of thermodynamics. The results indicated that the total energy and exergy efficiencies from biomass to fuel were 51.3% and 43.5%, respectively, with a negative CO(2) emission effect. The effects of gasification temperature, combustion temperature, and steam/biomass ratio on the gasification performance were investigated. The causes of exergy losses were analyzed to identify the areas of improvement so that a high energy utilization efficiency could be achieved.

Climate change mitigation demands large-scale technological change on a global level and, if successfully implemented, will significantly affect how products and services are produced and consumed. In order to anticipate the life cycle environmental impacts of products under climate mitigation scenarios, we present the modeling framework of an integrated hybrid life cycle assessment model covering nine world regions. Life cycle assessment databases and multiregional input-output tables are adapted using forecasted changes in technology and resources up to 2050 under a 2 °C scenario. We call the result of this modeling "technology hybridized environmental-economic model with integrated scenarios" (THEMIS). As a case study, we apply THEMIS in an integrated environmental assessment of concentrating solar power. Life-cycle greenhouse gas emissions for this plant range from 33 to 95 g CO2 eq./kWh across different world regions in 2010, falling to 30-87 g CO2 eq./kWh in 2050. Using regional life cycle data yields insightful results. More generally, these results also highlight the need for systematic life cycle frameworks that capture the actual consequences and feedback effects of large-scale policies in the long term.

Change in home heating to more efficient and renewable systems is important for a sound climate policy. The present paper aims to identify potential interventions for the uptake of wood-pellet heating in Norway using an agent-based model (ABM). The theoretically based, empirically founded, agent-based simulation demonstrates that financial support, i.e., a stable wood-pellet price, and technical development, i.e., functional reliability improvement, have to be established all at the same time for a successful wood-pellet market to start. Furthermore, a soft intervention through persuading households to use environmentally beneficial heating system is not a promising driver for wood-pellet diffusion. Limitations and suggestions for future work are also discussed.