Sectoral trends in global energy use and greenhouse gas emissions

Integrated assessment models have been used to project both baseline and mitigation greenhouse gas emissions scenarios. Results of these scenarios are typically presented for a number of world regions and end-use sectors, such as industry, transport, and buildings. Analysts interested in particular technologies and policies, however, require more detailed information to understand specific mitigation options in relation to business-as-usual trends. This paper presents sectoral trend for two of the scenarios produced by the Intergovernmental Panel on Climate Change's Special Report on Emissions Scenarios. Global and regional historical trends in energy use and carbon dioxide emissions over the past 30 years are examined and contrasted with projections over the next 30 years. Macro-activity indicators are analyzed as well as trends in sectoral energy and carbon demand. This paper also describes a methodology to calculate primary energy and carbon dioxide emissions at the sector level, accounting for the full energy and emissions due to sectoral activities.     

Prospects of India's energy and emissions for a long time frame

For any nation, sector-wise forecasts of energy demand and emissions are becoming valuable elements in devising its national and international policies relating to energy security, local environment, and global climate change. It is in this context that this work attempts to forecast India's possible energy demands and emissions adopting a key indicator approach on least cost generation expansion optimization methodology for a long time frame. This study developed key indicators for useful-energy demand for end-use sectors such as industry, commerce, and residence. Key indicators for transport sector and non-energy use sectors were developed on transport mobility demand and end-use fuel demand. The main drivers of these key indicators are socio-economic parameters. This work was conducted in a linear programmed (LP) TIMES G5 model on TIMES modeling framework for model horizon of 1990–2100. By the end of the 21st-century, India's energy demands are projected to be about 1825 Mtoe of primary energy, 1263 Mtoe of final energy consumption, 4840 TWh of electricity generations, 723 Mtoe of energy import, and 4414 Mt of CO₂ emissions.     

Reduction potentials of energy demand and GHG emissions in China's road transport sector

Rapid growth of road vehicles, private vehicles in particular, has resulted in continuing growth in China's oil demand and imports, which has been widely accepted as a major factor effecting future oil availability and prices, and a major contributor to China's GHG emission increase. This paper is intended to analyze the future trends of energy demand and GHG emissions in China's road transport sector and to assess the effectiveness of possible reduction measures. A detailed model has been developed to derive a reliable historical trend of energy demand and GHG emissions in China's road transport sector between 2000 and 2005 and to project future trends. Two scenarios have been designed to describe the future strategies relating to the development of China's road transport sector. The ‘Business as Usual’ scenario is used as a baseline reference scenario, in which the government is assumed to do nothing to influence the long-term trends of road transport energy demand. The ‘Best Case’ scenario is considered to be the most optimized case where a series of available reduction measures such as private vehicle control, fuel economy regulation, promoting diesel and gas vehicles, fuel tax and biofuel promotion, are assumed to be implemented. Energy demand and GHG emissions in China's road transport sector up to 2030 are estimated in these two scenarios. The total reduction potentials in the ‘Best Case’ scenario and the relative reduction potentials of each measure have been estimated.     

Genetic algorithm approach to estimate transport energy demand in Turkey

Transport energy modeling is a subject of current interest among transport engineers and scientists concerned with problems of sustainable transport. Transport energy planning is not possible without a reasonable knowledge of past and present energy consumption and likely future demands. In this study, three forms of the energy demand equations are developed in order to improve transport energy demand estimation efficiency for future projections based on genetic algorithm (GA) notion. The Genetic Algorithm Transport Energy Demand Estimation (GATEDE) model is developed using population, gross domestic product and vehicle-km. All equations proposed here are linear and non-linear, of which one is linear, second is exponential and third is quadratic. The quadratic form of the GATEDE model provided better-fit solution to the observed data and can be used with a high correlation coefficient for Turkey's future transport energy projections. It is expected that this study will be helpful in developing highly applicable and productive planning for transport energy policies. The GATEDE gives transport energy demand in comparison with the other transport energy demand projections. The GATEDE model plans the sectoral energy demand of Turkey until 2020.     

A review on emissions and mitigation strategies for road transport in Malaysia

The emissions from road transport are serious threats to urban air quality and global warming. The first step to develop effective policies is to determine the source and amount of emissions produced. This paper attempts to review emissions from road transport using COPERT 4 model and examined possible emission mitigation strategies. In road transport, results have show that passenger cars are the main cause of CO₂, N₂O and CO emissions, while motorcycles are main source of hydrocarbon (HC) emissions. However, light duty vehicles and heavy duty vehicles are the main contribution of particulate matters. The total CO₂ equivalent emissions for road transport in Malaysia are 59,383.51 ktonnes for year 2007. Further results show that CO₂ emission is the primary source of greenhouse gas pollution which is 71% of the total CO₂ equivalent. A parametric study was conducted to estimate the potential emission mitigation strategies for road transport by taking the emissions in 2007 as a reference year. It was observed that promoting the public transport is an effective strategy to reduce emissions and fuel consumption from the technical view point. It can totally save up to 1044 ktonnes of fuel consumption and total CO₂ equivalents emissions can be decreased by 7%. It was noted that, fleet renewal and promoting natural gas vehicles will significantly contribute in the reduction of emissions in Malaysia.     

Policies to reduce energy use and environmental emissions in the transport sector : A case of Delhi city

This paper aims to analyze factors influencing energy consumption pattern and emission levels in the transport sector of Delhi, and extrapolates total energy demand and the vehicular emissions, using a computer-based software called ‘Long Range Energy Alternative Planning’ (LEAP) and the associated ‘Environmental Database (EDB)’. The study is restricted to passenger modes of transport in Delhi and does not include the freight model. Travel demand is first estimated by analyzing data on vehicle population, average distance travelled, and occupancy level. Next, data on travel demand, proportion of travel demand catered by road and rail, modal split, occupancy and fuel efficiency are compiled within the LEAP framework, in order to estimate the energy demand in Delhi. In addition, emission factors are compiled under EDB module of the LEAP structure to estimate the resultant pollution loading. The LEAP model is run under five alternative scenarios to estimate the current consumption of gasoline and diesel oil in Delhi and forecast the same for the years 1994/1995, 2000/2001, 2004/2005 and 2009/2010, respectively. Under each scenario, the model also estimates emissions of CO, HC, NO_x, SO₂, Pb and TSP. The total emissions are translated into concentration levels attributable to the passenger transport to get an indication of air quality in Delhi. This is accomplished by the use of proportional air quality model. Finally, scenario results are analyzed to study the impact of different urban transport policy initiatives that will reduce the growth of fuel demand and emissions. The prime objective is to arrive at an optimal transport policy that limits the future growth of fuel consumption as well as air pollution.     

China's transportation energy consumption and CO2 emissions from a global perspective

Rapidly growing energy demand from China's transportation sector in the last two decades have raised concerns over national energy security, local air pollution, and carbon dioxide (CO₂) emissions, and there is broad consensus that China's transportation sector will continue to grow in the coming decades. This paper explores the future development of China's transportation sector in terms of service demands, final energy consumption, and CO₂ emissions, and their interactions with global climate policy. This study develops a detailed China transportation energy model that is nested in an integrated assessment model—Global Change Assessment Model (GCAM)—to evaluate the long-term energy consumption and CO₂ emissions of China's transportation sector from a global perspective. The analysis suggests that, without major policy intervention, future transportation energy consumption and CO₂ emissions will continue to rapidly increase and the transportation sector will remain heavily reliant on fossil fuels. Although carbon price policies may significantly reduce the sector's energy consumption and CO₂ emissions, the associated changes in service demands and modal split will be modest, particularly in the passenger transport sector. The analysis also suggests that it is more difficult to decarbonize the transportation sector than other sectors of the economy, primarily owing to its heavy reliance on petroleum products.     

Energy demand and greenhouse gas emissions from urban passenger transportation versus availability of renewable energy: The example of the Canadian Lower Fraser Valley

The energy consumption and greenhouse gas emissions of all private and transit vehicles from the Lower Fraser Valley, British Columbia, Canada are analysed for the year 2000. The energy figures are then compared with the Province's renewable energy potential. Results indicate that electric trolley buses and the automated rapid transit SkyTrain were eight times as energy efficient as private vehicles. These two modes were also 100 times as emission efficient as private vehicles in terms of greenhouse gas emitted per passenger-kilometer. Analysis of a minimal greenhouse gas emissions scenario, based on local renewable energy resources, electrolytic hydrogen production, and conversion of all private vehicles to fuel-cell technology indicates that such a strategy would utilize between 40% and 60% of the Province's renewable energy resources. We conclude that, if the use of renewable energy resources is chosen to reduce emissions from urban passenger transportation, probability of success will be increased by reducing the sector's energy demand through a transfer of ridership to the most energy efficient modes.     

A system dynamics approach to scenario analysis for urban passenger transport energy consumption and CO2 emissions: A case study of Beijing

With the accelerating process of urbanization, developing countries are facing growing pressure to pursue energy savings and emission reductions, especially in urban passenger transport. In this paper, we built a Beijing urban passenger transport carbon model, including an economy subsystem, population subsystem, transport subsystem, and energy consumption and CO₂ emissions subsystem using System Dynamics. Furthermore, we constructed a variety of policy scenarios based on management experience in Beijing. The analysis showed that priority to the development of public transport (PDPT) could significantly increase the proportion of public transport locally and would be helpful in pursuing energy savings and emission reductions as well. Travel demand management (TDM) had a distinctive effect on energy savings and emission reductions in the short term, while technical progress (TP) was more conducive to realizing emission reduction targets. Administrative rules and regulations management (ARM) had the best overall effect of the individual policies on both energy savings and emission reductions. However, the effect of comprehensive policy (CP) was better than any of the individual policies pursued separately. Furthermore, the optimal implementation sequence of each individual policy in CP was TP→PDPT→TDM→ARM.     

Examining the role of energy efficiency and non-economic factors in energy demand and CO2 emissions in Nigeria: Policy implications

This paper examines the role of energy efficiency and non-economic factors such as consumers' preferences, lifestyles and values (which have hitherto been ignored) in energy demand and CO₂ emissions modelling for Nigeria. We use a structural time series model to estimate various energy demand and CO₂ intensity models that take account of the aforementioned factors. We adopt preferred models from these estimates to analyse how energy demand and CO₂ emissions in Nigeria might evolve by generating three different future scenarios to 2025. We find energy efficiency and non-economic factors to influence energy demand and CO₂ emissions. The long-run income and price elasticities obtained differ significantly from those in existing studies that have ignored these salient factors. In a business-as-usual scenario, the results indicate that energy demand will continue to grow. Consequently, present policies do not sufficiently mitigate aggregate CO₂ emissions in Nigeria. The lesson for policy makers is that the extant policies introduced to restrain CO₂ emissions (from a production perspective) have to be combined with new policies that influence consumers' lifestyles and behaviours, develop energy efficient technologies and apply low tariffs on imported energy efficient appliances, to drive down CO₂ emissions from a consumption perspective.     

Scenario analysis on alternative fuel/vehicle for China’s future road transport: Life-cycle energy demand and GHG emissions

The rapid growth of vehicles has resulted in continuing growth in China’s oil demand. This paper analyzes future trends of both direct and life cycle energy demand (ED) and greenhouse gas (GHG) emissions in China’s road transport sector, and assesses the effectiveness of possible reduction measures by using alternative vehicles/fuels. A model is developed to derive a historical trend and to project future trends. The government is assumed to do nothing additional in the future to influence the long-term trends in the business as usual (BAU) scenario. Four specific scenarios are used to describe the future cases where different alternative fuel/vehicles are applied. The best case scenario is set to represent the most optimized case. Direct ED and GHG emissions would reach 734 million tonnes of oil equivalent and 2384 million tonnes carbon dioxide equivalent by 2050 in the BAU case, respectively, more than 5.6 times of 2007 levels. Compared with the BAU case, the relative reductions achieved in the best case would be 15.8% and 27.6% for life cycle ED and GHG emissions, respectively. It is suggested for future policy implementation to support sustainable biofuel and high efficient electric-vehicles, and the deployment of coal-based fuels accompanied with low-carbon technology.     

Projection of future transport energy demand of Thailand

The objective of this study is to project transport energy consumption in Thailand for the next 20 years. The study develops log-linear regression models and feed-forward neural network models, using the as independent variables national gross domestic product, population and the numbers of registered vehicles. The models are based on 20-year historical data between years 1989 and 2008, and are used to project the trends in future transport energy consumption for years 2010–2030. The final log-linear models include only gross domestic product, since all independent variables are highly correlated. It was found that the projection results of this study were in the range of 54.84–59.05 million tonnes of oil equivalent, 2.5 times the 2008 consumption. The projected demand is only 61–65% of that predicted in a previous study, which used the LEAP model. This major discrepancy in transport energy demand projections suggests that projects related to this key indicator should take into account alternative projections, because these numbers greatly affect plans, policies and budget allocation for national energy management.     

Electricity sector reforms in four Latin-American countries and their impact on carbon dioxide emissions and renewable energy

This paper analyzes carbon dioxide (CO₂) emissions related to energy consumption for electricity generation in four Latin-American countries in the context of the liberalization process. From 1990 to 2006, power plants based on renewable energy sources decreased its share in power installed capacity, and the carbon index defined as CO₂ emission by unit of energy for electricity production stayed almost constant for all countries with the exception of Colombia, where the index reduced due to increase in hydroelectricity generation in the last years. The paper also presents a new set of policies to promote renewable energy sources that have been developed in the four countries. The paper concludes that restructuring did not bring about environmental benefits related to a decrease in CO₂ emissions because this depend on the existence of committed policies, and dedicated institutional and regulatory frameworks.     

China's energy and emissions outlook to 2050: Perspectives from bottom-up energy end-use model

Although China became the world's largest CO₂ emitter in 2007, the country has also taken serious actions to reduce its energy and carbon intensity. This study uses the bottom-up LBNL China End-Use Energy Model to assess the role of energy efficiency policies in transitioning China to a lower emission trajectory and meeting its 2020 intensity reduction goals. Two scenarios – Continued Improvement and Accelerated Improvement – were developed to assess the impact of actions already taken by the Chinese government as well as planned and potential actions, and to evaluate the potential for China to reduce energy demand and emissions. This scenario analysis presents an important modeling approach based in the diffusion of end-use technologies and physical drivers of energy demand and thereby help illuminate China's complex and dynamic drivers of energy consumption and implications of energy efficiency policies. The findings suggest that China's CO₂ emissions will not likely continue growing throughout this century because of saturation effects in appliances, residential and commercial floor area, roadways, fertilizer use; and population peak around 2030 with slowing urban population growth. The scenarios also underscore the significant role that policy-driven efficiency improvements will play in meeting 2020 carbon mitigation goals along with a decarbonized power supply.     

Integrated energy and carbon modeling with a decision support system: Policy scenarios for low-carbon city development in Bangkok

Energy use in Bangkok accounts for a large portion of the total energy consumption in Thailand. Few energy and carbon studies, however, have focused on the level of the city. International research indicates that cities are the key drivers of energy usage and the associated carbon emissions. This paper presents a study on the options for energy and carbon development for the city of Bangkok. The Long-range Energy Alternatives Planning System (LEAP) model is used to simulate a range of policy interventions and to predict how these would change energy and carbon development from 2000 to 2025. The planning period is assumed to start in 2005, and 2000 is used as the baseline year. Sustainability of the sixteen proposed policies and scenarios is analyzed using a multi-criteria decision-making approach. Results of this study provide an insight into Bangkok's energy and carbon future and highlight the steps required to promote a sustainable low-carbon society. The most significant energy savings are in the transport sector, where a modal shift from private passenger vehicles to mass transit systems has the potential to significantly reduce energy demand, carbon emissions, and local air pollutants.     

Comparative life cycle assessment of hydrogen pathways from fossil sources in China

Emissions of multiple hydrogen production pathways from fossil sources were evaluated and compared with that of fossil fuel production pathways in China by using the life cycle assessment method. The considered hydrogen pathways are gasoline reforming, diesel reforming, natural gas reforming, soybean‐derived biodiesel (s‐biodiesel) reforming, and waste cooking oil‐derived biodiesel reforming. Moreover, emissions and energy consumption of fuel cell vehicles utilizing hydrogen from different fossil sources were presented and compared with those of the electric vehicle, the internal combustion engine vehicle, and the compression ignition engine vehicle. The results indicate both fuel cell vehicles and the electric vehicle have less greenhouse gas emissions and energy consumption compared with the traditional vehicle technologies in China. Based on an overall performance comparison of five different fuel cell vehicles and the electric vehicle in China, fuel cell vehicles operating on hydrogen produced from natural gas and waste cooking oil‐derived biodiesel show the best performance, whereas the electric vehicle has the worse performance than all the fuel cell vehicles because of very high share of coal in the electricity mix of China. The emissions of electric vehicle in China will be in the same level with that of natural gas fuel cell vehicle if the share of coal decreases to around 40% and the share of renewable energy increases to around 20% in the electricity mix of China. Copyright © 2016 John Wiley & Sons, Ltd.     

Light vehicle energy efficiency programs and their impact on Brazilian CO2 emissions

This paper analyses the impact of an energy efficiency program for light vehicles in Brazil on emissions of carbon dioxide (CO₂), the main greenhouse gas in the atmosphere. Several energy efficiency programs for light vehicles around the world are reviewed. The cases of Japan and Europe were selected for presentation here given their status as current and future world leaders in the control of passenger vehicle fuel consumption. The launching of the National Climate Change Plan and the pressure on the Brazilian car industry due to the world financial crisis make it a good time for the Brazilian government to implement such a program, and its various benefits are highlighted in this study. Three scenarios are established for Brazil covering the 2000–2030 period: the first with no efficiency goals, the second with the Japanese goals applied with a 10 years delay, and the third, with the Japanese goals applied with no delay. The consequences of a vehicular efficiency program and its middle and long-term effects on the consumption of energy and the CO₂ emissions are quantified and discussed. The simulation results indicate that efficiency goals may make an important contribution to reducing vehicular emissions and fuel consumption in Brazil, compared to a baseline scenario.     

Impact of urban development on residents’ public transportation travel energy consumption in China: An analysis of hydrogen fuel cell vehicles alternatives

Urban development has an important influence on the energy consumption of transportation. To develop public transportation is one of the important ways to decrease the energy consumption of urban transportation. It is very urgent to upgrade technology to reduce the energy consumption and emissions of the vehicles constantly. The popularization of hydrogen fuel cell vehicles is the trend of the future automobile industry, which can effectively reduce traffic energy consumption and alleviate urban pollution. This article analyzes the impact of urban development on public transport and private transportation energy consumption from 2013 to 2015; and uses hydrogen fuel cell vehicles alternatives in urban public transport as a scenario. It shows that urban economic development can effectively reduce public transport. Population growth will increase greatly energy consumption of public transport, while larger cities with reasonable spatial density can reduce traffic energy consumption. Moreover, hydrogen fuel cell vehicles can effectively reduce the energy consumption and pollution emissions of urban transportation during operating. Based on the above conclusions, this article will eventually provide targeted recommendations for the development of Chinese cities, public transport, and hydrogen fuel cell vehicles.     

Energy demand and CO2 emissions reduction options in Nigeria

This paper presents policy options for reducing CO₂ emissions in Nigeria. The policies were formulated based on a thorough analysis of Nigeria's current energy consumption patterns and the projected evolution of key parameters that drive Nigeria's energy demand — primarily the rate of industrialization, the demand for transportation services, and the expansion of Nigeria's population. The study shows that the most promising options for reducing CO₂ emissions in Nigeria are improving energy efficiency and increasing the use of natural gas and renewable energy sources.     

Energy demand and emissions from road transportation vehicles in China

Rapidly growing energy demand and emissions from China's road transportation vehicles in the last two decades have raised concerns over oil security, urban air pollution and global warming. This rapid growth will be likely to continue in the next two to three decades as the vehicle ownership level in China is still very low. The current status of China's road transport sector in terms of vehicles, infrastructure, energy use and emissions is presented. Mitigation measures implemented and those that can reasonably be expected to be adopted in the near future are analysed. Recent studies exploring the future trends of road vehicle energy demand and emissions under various strategies are reviewed. Moreover, those studies which assessed various fuel/propulsion options in China from a life cycle perspective are examined to present an overview of the potential for reducing energy use and emissions. Recommendations for further developments are also made. It is concluded that comprehensive and appropriate strategies will be needed to minimise the adverse impacts of China's road vehicles on energy resources and the environment. Fortunately, China appears to be heading in this direction.