CO2 emissions from electricity generation in seven Asia-Pacific and North American countries: A decomposition analysis

The Logarithmic Mean Divisia Index (LMDI) method of complete decomposition is used to examine the role of three factors (electricity production, electricity generation structure and energy intensity of electricity generation) affecting the evolution of CO₂ emissions from electricity generation in seven countries. These seven countries together generated 58% of global electricity and they are responsible for more than two-thirds of global CO₂ emissions from electricity generation in 2005. The analysis shows production effect as the major factor responsible for rise in CO₂ emissions during the period 1990–2005. The generation structure effect also contributed in CO₂ emissions increase, although at a slower rate. In contrary, the energy intensity effect is responsible for modest reduction in CO₂ emissions during this period. Over the 2005–2030 period, production effect remains the key factor responsible for increase in emissions and energy intensity effect is responsible for decrease in emissions. Unlike in the past, generation structure effect contributes significant decrease in emissions. However, the degree of influence of these factors affecting changes in CO₂ emissions vary from country to country. The analysis also shows that there is a potential of efficiency improvement of fossil-fuel-fired power plants and its associated co-benefits among these countries.     

Modeling the prospects of plug-in hybrid electric vehicles to reduce CO2 emissions

This study models the CO₂ emissions from electric (EV) and plug-in hybrid electric vehicles (PHEV), and compares the results to published values for the CO₂ emissions from conventional vehicles based on internal combustion engines (ICE). PHEVs require fewer batteries than EVs which can make them lighter and more efficient than EVs. PHEVs can also operate their onboard ICEs more efficiently than can conventional vehicles. From this, it was theorized that PHEVs may be able to emit less CO₂ than both conventional vehicles and EVs given certain power generation mixes of varying CO₂ intensities. Amongst the results it was shown that with a highly CO₂ intensive power generation mix, such as in China, PHEVs had the potential to be responsible for fewer tank to wheel CO₂ emissions over their entire range than both a similar electric and conventional vehicle. The results also showed that unless highly CO₂ intensive countries pursue a major decarbonization of their power generation, they will not be able to fully take advantage of the ability of EVs and PHEVs to reduce the CO₂ emissions from automotive transport.     

Examining the driving forces for improving China’s CO2 emission intensity using the decomposing method

This paper examines the driving forces for reducing China’s CO₂ emission intensity between 1998 and 2008, utilizing the logarithmic mean divisia index (LMDI) technique. By first grouping the CO₂ emissions into two categories, those arising from activities related to the electric power industry and those from other sources, emission intensity is further broken down into the effects of the CO₂ emission coefficient, energy intensity of power generation, power generation and consumption ratio, electricity intensity of the gross domestic product (GDP), provincial structural change, and the energy intensity of the GDP for other activities. The decomposition results show that improvements in the energy intensity of power generation, electricity intensity of GDP, and energy intensity of GDP for other activities were mainly responsible for the success in reducing China’s CO₂ emission intensity and that activities related to the electric power industry played a key role. It is also revealed that performance varied significantly at the individual province level. The provinces with higher emission levels contributed the most to China’s improvements in CO₂ emission intensity.     

Assessing the cost-effectiveness of electric vehicles in European countries using integrated modeling

Electric vehicles (EVs) are considered alternatives to internal combustion engines due to their energy efficiency and contribution to CO₂ mitigation. The adoption of EVs depends on consumer preferences, including cost, social status and driving habits, although it is agreed that current and expected costs play a major role. We use a partial equilibrium model that minimizes total energy system costs to assess whether EVs can be a cost-effective option for the consumers of each EU27 member state up to 2050, focusing on the impact of different vehicle investment costs and CO₂ mitigation targets. We found that for an EU-wide greenhouse gas emission reduction cap of 40% and 70% by 2050 vis-à-vis 1990 emissions, battery electric vehicles (BEVs) are cost-effective in the EU only by 2030 and only if their costs are 30% lower than currently expected. At the EU level, vehicle costs and the capability to deliver both short- and long-distance mobility are the main drivers of BEV deployment. Other drivers include each state’s national mobility patterns and the cost-effectiveness of alternative mitigation options, both in the transport sector, such as plug-in hybrid electric vehicles (PHEVs) or biofuels, and in other sectors, such as renewable electricity.     

对我国发展纯电动汽车的质疑与思考

近年来国家对纯电动汽车的扶持力度正在不断加大。然而纯电动汽车、混合动力汽车等以电力作燃料,并非真正意义上的新能源汽车。纯电动汽车所消耗的电力需要由发电厂提供,相当于以煤代油,其外部负效应表现在燃煤电厂的负效应上。燃油汽车和纯电动汽车每辆车每年的能耗折算成标煤分别为1.53t和1.6t,基本上相等,但燃油排放的二氧化碳比燃煤少,所以纯电动汽车并不是低碳汽车。用纯电动汽车替代燃油汽车,很可能是减少了石油进口,但却要增加煤炭进口,并不能从根本上提高我国能源的安全性。发展纯电动汽车需要大量投资,再加上环境污染,经济性很差。鉴于此,建议我国应重新定义新能源汽车,要真正利用新能源作为汽车的动力,寻找适合我国能源资源条件的真正的新能源汽车或替代能源汽车;中国在相当长的时间里节能减排还是主要依靠传统燃油汽车,在重视研发新能源汽车、研究替代燃油汽车的同时,应重视传统燃油汽车的节能降耗;控制汽车消费是最有效的节油措施;节能减排必须要从一次能源算起,我国电源结构以煤电为主,并不适宜发展纯电动汽车。中国要等到第一次和第二次能源大转换完成之后,当天然气、水电、核电在电源结构中占据主体地位时,纯电动汽车才会有广阔的发展前景。     

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.     

Foreign trade and declining pollution in Sweden: a decomposition analysis of long-term structural and technological effects

This article examines whether there exists any causal relationship between foreign trade and declining pollution in developed countries. In other words, do developed countries outsource their problems to less developed countries rather than solve them? The case study is the Swedish economy and the two environmental indicators employed are energy consumption and CO₂ emissions. No causal relationships are found, since Sweden has long been a net exporter of embodied energy and CO₂ and continues to be so after 1970, when energy consumption stabilizes and CO₂ emissions decline. In addition, the ratios of net exported energy and CO₂ to total consumption remain stable, which means there were no effects on the energy intensity or CO₂ intensity either. These results suggest that internal forces, like efficiency improvements, changed consumption patterns and transformation of the energy system, have been crucial for relative environmental improvement in Sweden, while foreign trade has played no role.     

US marginal electricity grid mixes and EV greenhouse gas emissions

Battery electric vehicles (BEVs) are often portrayed as “green,” implying negligible greenhouse gas (GHG) emissions. While BEVs are zero emission vehicles, the electrical power generators used to recharge vehicle batteries do emit copious GHGs. Some analysts have estimated the power plant GHG emissions due to charging EV batteries using the average electrical generator grid mix for a given region. However, the GHG protocol specifies that analysts should use the marginal grid mixes to accurately calculate GHG emissions from adding EVs to the vehicle fleet. This paper utilizes the marginal grid mixes for each electrical power region in the US, and calculates the vehicle-weighted average GHG emissions for the entire country. These calculations demonstrate that, on the average, each BEV that displaces a gasoline hybrid electric vehicle (HEV) will increase GHGs by more than 7% and each PHEV put in service will increase GHGs by an average of 10% compared to a gasoline HEV.     

Factors affecting CO2 emission from the power sector of selected countries in Asia and the Pacific

This study analyzes the key factors behind the CO₂ emissions from the power sector in fifteen selected countries in Asia and the Pacific using the Log-Mean Divisia Index method of decomposition. The roles of changes in economic output, electricity intensity of the economy, fuel intensity of power generation and generation structure are examined in the evolution of CO₂ emission from the power sector of the selected countries during 1980–2004. The study shows that the economic growth was the dominant factor behind the increase in CO₂ emission in ten of the selected countries (i.e., Australia, China, India, Japan, Malaysia, Pakistan, South Korea, Singapore, Thailand and Vietnam, while the increasing electricity intensity of the economy was the main factor in three countries (Bangladesh, Indonesia and Philippines). Structural changes in power generation were found to be the main contributor to changes in the CO₂ emission in the case of Sri Lanka and New Zealand.     

Effects of nuclear power plant shutdowns on electricity consumption and greenhouse gas emissions after the Tohoku Earthquake

This study analyzes how the substitution of fossil fuels for nuclear power due to the shutdown of nuclear power plants after the Tohoku Earthquake affects electricity consumption and greenhouse gas emissions in Japan. Results indicate that Japan generated 4.3 million metric tons (or 0.3%, with a 95% confidence interval) of additional CO₂ emissions in 2011 following the earthquake. The increase in CO₂ emissions stemmed from the combined effects of decreased electricity consumption due to energy conservation efforts and the substitution of fossil fuels for nuclear power following the Tohoku Earthquake. Results also show considerable spatial variation in the impacts of the earthquake on net CO₂ emissions. A majority of the prefectures (40 of 47 prefectures, or 85%) were predicted to experience higher CO₂ emissions after the Tohoku Earthquake while the remaining (7 prefectures) were predicted to experience lower CO₂ emissions. Our findings suggest that Japan and countries under similar risks may want to reformulate energy policy by emphasizing utilization of diverse power and energy sources, including more renewable energy production and electricity conservation. The policy reform should also consider spatial variation in the combined effects of reduced reliance on nuclear power and increased CO₂ conversion factors.     

Can EV (electric vehicles) address Ireland’s CO2 emissions from transport?

In the period 1990–2007, CO₂ emissions from Ireland’s Transport sector increased by 181%. It has been proposed that a transition to EV (electrically-powered vehicles) – either BEV (battery-powered) or PHEV (plug-in hybrids) – offers the potential for significant reductions in these emissions. However, the benefits of PHEV – and of plug-in vehicles generally – accrue because some fraction of the fossil fuel normally consumed by the vehicle is displaced by electricity extracted from the national grid. The net benefit therefore depends on many factors, including the characteristics of the electricity generation and distribution system, and the proportion of vkm (vehicle-kilometres) completed under electric power.     

Determinants of carbon dioxide emissions: Empirical evidence from 69 countries

This study investigates the determinants of carbon dioxide emissions (CO₂) for a global panel consisting of 69 countries using a dynamic panel data model. To make the panel data analysis more homogenous, we also investigate the determinants of CO₂ emissions for a number of sub-panels. These sub-panels are constructed based on the income level of countries. In this way, we end up with three income panels; namely, high income, middle income, and low income panels. The time component of our dataset is 1985–2005 inclusive. Our main findings are that trade openness, per capita GDP, and energy consumption, proxied by per capita electric power consumption and per capita total primary energy consumption, have positive effects on CO₂ emissions. Urbanisation is found to have a negative impact on CO₂ emissions in high income, middle income, and low income panels. For the global panel, only GDP per capita and per capita total primary energy consumption are found to be statistically significant determinants of CO₂ emission, while urbanisation, trade openness, and per capita electric power consumption have negative effects on the CO₂ emissions.     

An integral evaluation of dieselisation policies for households’ cars

Reducing energy consumption and CO₂ emissions in the transport sector is a priority for Great Britain and other European countries as part of their agreements made in the Kyoto protocol and the Voluntary Agreement. To achieve these goals, it has been proposed to increase the market share of diesel vehicles which are more efficient than petrol ones. Based on partial approaches, previous research concluded that increasing the share of diesel vehicles will decrease CO₂ emissions (see 1 and 18; Zervas, 2006). Unlike these approaches, I use an integral approach based on discrete choice models to analyse diesel vehicle penetration in a broader context of transport in Great Britain. I provide for the first time, empirical evidence which is in line with Bonilla's (2009) argument that only improvements in vehicle efficiency will not be enough to achieve their goals of mitigation of energy consumption and CO₂ emissions. The model shows the technical limitations that the penetration of diesel vehicles faces and that a combination of improvements in public transportation and taxes on fuel prices is the most effective policy combination to reduce the total amount of energy consumption and CO₂ emissions among the analysed dieselisation polices.     

Analysis of the vehicle mix in the passenger-car sector in Japan for CO2 emissions reduction by a MARKAL model

Carbon dioxide (CO₂) emissions from the passenger-car sector in Japan are increasing rapidly and should be reduced cost-effectively in order to stabilize energy-related CO₂ emissions in Japan. The purpose of the present paper is to clarify the most cost-effective mix of vehicles for reducing CO₂ emissions and to estimate the subsidy that is necessary to achieve this vehicle mix. For this analysis, the energy system of Japan from 1988 to 2032 is modeled using a MARKAL model. The most cost-effective mix of vehicles is estimated by minimizing the total energy system cost under the constraint of an 8% energy-related CO₂ emissions reduction nationally by 2030 from the CO₂ emissions of 1990. Based on the results of the analysis, hybrid vehicles are the only type of clean-energy vehicle, and their share of the passenger car sector in 2030 will be 62%. By assuming the subsidization of hybrid vehicles, the same vehicle mix can be achieved without constraining CO₂ emissions. The peak of the total subsidy estimated to be necessary is 1.225 billion US$/year in 2020, but the annual revenue of the assumed 31 US$/t-C carbon tax from the passenger car sector is sufficient to finance the estimated subsidy. This suggests that we should support the dissemination of hybrid vehicles through subsidization based on carbon tax.     

Plug-in hybrid fuel cell vehicles market penetration scenarios

The main objective of this research is to analyze the impact of the market share increase of hydrogen based road vehicles in terms of energy consumption and CO₂, on today's Portuguese light-duty fleet. Actual yearly values of energy consumption and emissions were estimated using COPERT software: 167112 TJ of fossil fuel energy, 12213 kton of CO₂ emission and 141 kton of CO, 20 kton of HC, 46 kton of NO_x and 3 kton of PM. These values represent 20–40% of countries total emissions. Additionally to base fleet, three scenarios of introduction of 10–30% fuel cell vehicles including plug-in hybrids configurations were analysed. Considering the scenarios of increasing hydrogen based vehicles penetration, up to 10% life cycle energy consumption reduction can be obtained if hydrogen from centralized natural gas reforming is considered. Full life cycle CO₂ emissions can also be reduced up to 20% in these scenarios, while local pollutants reach up to 85% reductions. For the purpose of estimating road vehicle technologies energy consumption and CO₂ emissions in a full life cycle perspective, fuel cell, conventional full hybrids and hybrid plug-in technologies were considered with diesel, gasoline, hydrogen and biofuel blends. Energy consumption values were estimated in a real road driving cycle and with ADVISOR software. Materials cradle-to-grave life cycle was estimated using GREET database adapted to Europe electric mix. The main conclusions on CO₂ full life cycle analysis is that light-duty vehicles using fuel cell propulsion technology are highly dependent on hydrogen production pathway. The worst scenario for the current Portuguese and European electric mix is hydrogen produced from on-site electrolysis (in the refuelling stations). In this case full life cycle CO₂ is 270 g/km against 190 g/km for conventional Diesel vehicle, for a typical 150,000 km useful life.     

Integration of plug-in hybrid electric vehicles in a regional wind-thermal power system

This study investigates consequences of integrating plug-in hybrid electric vehicles (PHEVs) in a wind-thermal power system supplied by one quarter of wind power and three quarters of thermal generation. Four different PHEV integration strategies, with different impacts on the total electric load profile, have been investigated. The study shows that PHEVs can reduce the CO₂-emissions from the power system if actively integrated, whereas a passive approach to PHEV integration (i.e. letting people charge the car at will) is likely to result in an increase in emissions compared to a power system without PHEV load. The reduction in emissions under active PHEV integration strategies is due to a reduction in emissions related to thermal plant start-ups and part load operation. Emissions of the power sector are reduced with up to 4.7% compared to a system without PHEVs, according to the simulations. Allocating this emission reduction to the PHEV electricity consumption only, and assuming that the vehicles in electric mode is about 3 times as energy efficient as standard gasoline operation, total emissions from PHEVs would be less than half the emissions of a standard car, when running in electric mode.     

Long-term trends of electric efficiencies in electricity generation in developing countries

This analysis provides time-series data on electric efficiencies for 138 countries and regions, covering all fossil fuels for the period 1971–2005, with an emphasis on non-Organization for Economic Cooperation and Development (OECD) countries. Fossil fuel consumption for electricity generation in non-OECD countries now exceeds that in the OECD. The historical performance of the top five non-OECD consumers of each fossil fuel for which reliable data are available is presented and discussed. For each fuel, the countries that lead the world in efficiency are used for benchmarks; bringing the rest of the world up to these standards would result in energy savings of 26 EJ (equivalent to 5% of global energy consumption) and CO₂ emissions reduction of 2.1 Pg (equivalent to 8% of global CO₂ emissions). Coal showed the largest potential margin of improvement for both energy and CO₂, with possible savings equivalent to 3% of current global energy consumption and 5% of global CO₂ emissions. The gap in electric efficiency between OECD and non-OECD countries over the past 35 years has widened for coal-fired generation, stayed relatively constant for natural gas, but has shrunk for petroleum. The results show the very gradual nature of overall efficiency improvements and the significant differences among regions and countries.     

The feasibility of long range battery electric cars in New Zealand

New Zealand transport accounts for over 40% of the carbon emissions with private cars accounting for 25%. In the Ministry of Economic Development's recently released “New Zealand Energy Strategy to 2050”, it proposed the wide scale deployment of electric vehicles as a means of reducing carbon emissions from transport. However, New Zealand's lack of public transport infrastructure and its subsequent reliance on private car use for longer journeys could mean that many existing battery electric vehicles (BEVs) will not have the performance to replace conventionally fuelled cars.As such, this paper discusses the potential for BEVs in New Zealand, with particular reference to the development of the University of Waikato's long-range UltraCommuter BEV. It is shown that to achieve a long range at higher speeds, BEVs should be designed specifically rather than retrofitting existing vehicles to electric. Furthermore, the electrical energy supply for a mixed fleet of 2 million BEVs is discussed and conservatively calculated, along with the number of wind turbines to achieve this. The results show that approximately 1350 MW of wind turbines would be needed to supply the mixed fleet of 2 million BEVs, or 54% of the energy produced from NZ's planned and installed wind farms.     

Impact of electric vehicles on a future renewable energy‐based power system in Europe with a focus on Germany

Electric mobility is expected to play a key role in the decarbonisation of the energy system. Continued development of battery electric vehicles is fundamental to achieving major reductions in the consumption of fossil fuels and of CO₂ emissions in the transport sector. Hydrogen can become an important complementary synthetic fuel providing electric vehicles with longer ranges. However, the environmental benefit of electric vehicles is significant only if their additional electricity consumption is covered by power production from renewable energy sources. Analysing the implications of different scenarios of electric vehicles and renewable power generation considering their spatial and temporal characteristics, we investigate possible effects of electric mobility on the future power system in Germany and Europe. The time horizon of the scenario study is 2050. The approach is based on power system modelling that includes interchange of electricity between European regions, which allows assessing long‐term structural effects in energy systems with over 80% of renewable power generation. The study exhibits strong potential of controlled charging and flexible hydrogen production infrastructure to avoid peak demand increases and to reduce the curtailment of renewable power resulting in reduced system operation, generation, and network expansion costs. A charging strategy that is optimised from a systems perspective avoids in our scenarios 3.5 to 4.5 GW of the residual peak load in Germany and leads to efficiency gains of 10% of the electricity demand of plug‐in electric vehicles compared with uncontrolled loading.     

Structural decomposition analysis of energy-related CO<Subscript>2</Subscript> emissions in China from 1997 to 2010

The energy-related CO₂ emissions in China have increased dramatically from 3384 to 8333?×?10⁶ t during the last decade. To interpret these drastic changes, we undertake a structural decomposition analysis to decompose the changes in CO₂ emissions from 1997 to 2010 into the following six driving forces: emission coefficient, energy intensity, Leontief, sectoral structure, demand allocation (the shares of consumption, investments, and exports in final demand), and final demand effects. The results show that declines in energy intensity had a decrease impact on CO₂ emissions during the studied period. Changes in the relative importance of intermediate production in total output (the Leontief effect) contributed to decrease CO₂ emissions in the 2000–2002 period and to increase emissions in the other periods. The most important driver behind the steady increase in CO₂ emissions is the large increase in final demand. A further analysis at the sectoral level revealed differences and fluctuations between sectors. Energy intensity fell most strongly in the electric power sector and the coking, gas, and petroleum production sector (two energy-intensive sectors). The shift toward exports and investment increased CO₂ emissions (demand allocation effect). Part of the increases in CO₂ emissions thus stem from production activities for consumption activities elsewhere.