Transport demand for energy: a case study for Kuwait

This paper presents a model for the demand for oil products in the transport sector of Kuwait using a time‐series data for the period 1975–1995. The results indicate that the demand for gasoline is inelastic with respect to price and income in the short and long run. The demand has a short‐run elasticity which approaches unity when it comes to the average fuel economy of the fleet of automobiles which indicate a rapid response to changes in the automobiles technology. Furthermore, the results reveal that diesel fuel consumption is price and income inelastic in the short‐run but exceed perfectly elasticity in the long‐run. As for the case of aviation fuel, the demand is inelastic with respect to the price in the short run but it exceeds unit elasticity with respect to the number of flights landed in Kuwait which indicate that the activity variable is more significant in determining the demand for aviation fuel than its own price. Copyright © 1999 John Wiley & Sons, Ltd.     

中国农村能源温室气体主要减排技术评价及潜力分析

农村能源减排技术是优化能源结构,减少温室气体排放的重要途径之一,有利于实现国家温室气体减排的目标。文章综合分析评价了农村能源温室气体减排技术,计算减排效果并估算未来的减排潜力。结果表明,2009年中国主要农村能源技术温室气体减排量为8 529万tCO2,测算到2020年,中国农村能源温室气体的减排潜力约为2.97亿t CO2。农村户用沼气、生物质固体成型燃料、太阳能热利用等农村节能减排技术已基本成熟,实现了产业化应用,且减排潜力较大,是未来推广的重点。     

Potential benefits of cool roofs on commercial buildings: conserving energy, saving money, and reducing emission of greenhouse gases and air pollutants

Cool roofs—roofs that stay cool in the sun by minimizing solar absorption and maximizing thermal emission—lessen the flow of heat from the roof into the building, reducing the need for space cooling energy in conditioned buildings. Cool roofs may also increase the need for heating energy in cold climates. For a commercial building, the decrease in annual cooling load is typically much greater than the increase in annual heating load. This study combines building energy simulations, local energy prices, local electricity emission factors, and local estimates of building density to characterize local, state average, and national average cooling energy savings, heating energy penalties, energy cost savings, and emission reductions per unit conditioned roof area. The annual heating and cooling energy uses of four commercial building prototypes—new office (1980+), old office (pre-1980), new retail (1980+), and old retail (pre-1980)—were simulated in 236 US cities. Substituting a weathered cool white roof (solar reflectance 0.55) for a weathered conventional gray roof (solar reflectance 0.20) yielded annually a cooling energy saving per unit conditioned roof area ranging from 3.30 kWh/m² in Alaska to 7.69 kWh/m² in Arizona (5.02 kWh/m² nationwide); a heating energy penalty ranging from 0.003 therm/m² in Hawaii to 0.14 therm/m² in Wyoming (0.065 therm/m² nationwide); and an energy cost saving ranging from 0.126/m < sup > 2 < /sup > in West Virginia to0.126/m² in West Virginia to 1.14/m² in Arizona ($0.356/m² nationwide). It also offered annually a CO₂ reduction ranging from 1.07 kg/m² in Alaska to 4.97 kg/m² in Hawaii (3.02 kg/m² nationwide); an NO_x reduction ranging from 1.70 g/m² in New York to 11.7 g/m² in Hawaii (4.81 g/m² nationwide); an SO₂ reduction ranging from 1.79 g/m² in California to 26.1 g/m² in Alabama (12.4 g/m² nationwide); and an Hg reduction ranging from 1.08 μg/m² in Alaska to 105 μg/m² in Alabama (61.2 μg/m² nationwide). Retrofitting 80% of the 2.58 billion square meters of commercial building conditioned roof area in the USA would yield an annual cooling energy saving of 10.4 TWh; an annual heating energy penalty of 133 million therms; and an annual energy cost saving of $0.356/m² nationwide). It also offered annually a CO₂ reduction ranging from 1.07 kg/m² in Alaska to 4.97 kg/m² in Hawaii (3.02 kg/m² nationwide); an NO_x reduction ranging from 1.70 g/m² in New York to 11.7 g/m² in Hawaii (4.81 g/m² nationwide); an SO₂ reduction ranging from 1.79 g/m² in California to 26.1 g/m² in Alabama (12.4 g/m² nationwide); and an Hg reduction ranging from 1.08 μg/m² in Alaska to 105 μg/m² in Alabama (61.2 μg/m² nationwide). Retrofitting 80% of the 2.58 billion square meters of commercial building conditioned roof area in the USA would yield an annual cooling energy saving of 10.4 TWh; an annual heating energy penalty of 133 million therms; and an annual energy cost saving of 735 million. It would also offer an annual CO₂ reduction of 6.23 Mt, offsetting the annual CO₂ emissions of 1.20 million typical cars or 25.4 typical peak power plants; an annual NO_x reduction of 9.93 kt, offsetting the annual NO_x emissions of 0.57 million cars or 65.7 peak power plants; an annual SO₂ reduction of 25.6 kt, offsetting the annual SO₂ emissions of 815 peak power plants; and an annual Hg reduction of 126 kg.     

Long term perspectives of the U.S. energy demand: Application of the MEDEE 2 model to the U.S.

This paper gives a brief outline of a model, MEDEE 2, designed to evaluate the long term energy demand of a country and describes how it has been applied to the United States. The energy demand projections were carried out for the years 1985 and 2000 based upon three scenarios. According to these scenarios, the final energy demand will grow from 60 quads in 1975 to a value between 76 and 88 quads in 2000 (a quad is very close to 10¹⁸ joules), which implies a growth of the per capita energy demand from 10 kW to a value between 10.8 and 12.5 in 2000.     

ACROPOLIS: An example of international collaboration in the field of energy modelling to support greenhouse gases mitigation policies

Energy models are considered as valuable tools to assess the impact of various energy and environment policies. The ACROPOLIS initiative, supported by the European Commission and the International Energy Agency, used up to 15 energy models to simulate and evaluate selected policy measures and instruments and then compare their impacts on energy systems essentially in terms of costs of greenhouse gas emissions (GHG) reduction and energy technology choice. Four case studies are formulated considering policies and measures on renewable portfolio schemes and internationally tradable green certificates, emissions trading and global GHG abatement target, energy efficiency standards and internalisation of external costs. The main focus of the project is on the electricity sector. From a large set of quantified results, ACROPOLIS provides an international scientific consensus, on some key issues, which could be useful in assessing and designing energy and environment policies at the world, European and national/regional levels. It concludes that the Kyoto targets (and their continuation beyond 2010 in specific scenarios) could be achieved at a cost around 1% of GDP through global emissions trading, indicating also that this flexibility mechanism is a more cost-effective instrument for GHG mitigation than meeting the goal domestically without trade. It demonstrates that internalising external costs through a price increase reduces local pollutants (SO_x, NO_x, and others) and it produces other benefits such as triggering the penetration of clean technologies in addition to the curbing of CO₂ emissions.     

Transport and recombination in solar cells: New perspectives

The functioning of the solar cells relies on the photo-generation of carriers in p–n junctions and their subsequent recombination in the quasi-neutral regions. A number of basic issues concerning the physics of the operation of solar cells still remain obscure. This paper reports on some unsolved basic problems, namely: a model of the recombination processes that does not contradict Maxwell's equations; the role played by space charges in the transport phenomena, and the formation of quasi-neutral regions under the presence of non-equilibrium photo-generated carriers. In this work, a new formulation of the theory that explains the underlying physical phenomena involved in the generation of a photo-e.m.f. is presented.     

Transport demand,harmful emissions,environment and health co-benefits in China

The Chinese residents' travel demand has been increasing dramatically. As a result, emissions from motor vehicles have been found as one main source of air pollution in China, which consequently influences the residents' health. To better understand the environmental deterioration and health losses caused by the transport sector in China, in current circumstances, one must know how the changes in residents' travel demand and alternative transport modes affect environment and health co-benefits in China. We first of all calculate the demand from nearly all the residents' travel means, including road, rail, water, and air transport. Besides, based on the results, this paper further makes projections for a business-as-usual scenario for 2050 with several alternative transport scenarios to reduce harmful emissions and improve the welfare of the residents' health in China. Our integrated framework includes the harmful emissions models, the fixed box model and the exposure-response models, to link transport demand with possible environmental and health outcomes. The findings suggest that significant environment and health co-benefits are possible if alternative transport replaces. This research, to the best of our knowledge, is the first attempt to estimate the total resident's travel demand under different scenarios and the consequent environment and health co-benefits in the transitional China.     

Solar energy in India: Strategies, policies, perspectives and future potential

Renewable energy sources and technologies have potential to provide solutions to the longstanding energy problems being faced by the developing countries like India. Solar energy can be an important part of India's plan not only to add new capacity but also to increase energy security, address environmental concerns, and lead the massive market for renewable energy. Solar thermal electricity (STE) also known as concentrating solar power (CSP) are emerging renewable energy technologies and can be developed as future potential option for electricity generation in India. In this paper, efforts have been made to summarize the availability, current status, strategies, perspectives, promotion policies, major achievements and future potential of solar energy options in India.     

Renewable energy sources in the Colombian energy policy, analysis and perspectives

In this work; five basic elements for the formulation of a policy on renewable energy sources for Colombia, are discussed. A balance of the institutions of the energy sector related to the formulation, elaboration and execution of plans, programs and projects on renewable energy sources is carried out. The technology costs that take advantage of such sources are compared and the 967 Law issued in 2001 and its regulatory decree are analyzed. This law promotes the efficient and rational use of energy and also promotes the alternative energies.     

Breaking down the silos: the integration of energy efficiency, renewable energy, demand response and climate change

This paper explores the feasibility of integrating energy efficiency program evaluation with the emerging need for the evaluation of programs from different “energy cultures” (demand response, renewable energy, and climate change). The paper reviews key features and information needs of the energy cultures and critically reviews the opportunities and challenges associated with integrating these with energy efficiency program evaluation. There is a need to integrate the different policy arenas where energy efficiency, demand response, and climate change programs are developed, and there are positive signs that this integration is starting to occur.

Energy demand and supply,energy policies,and energy security in the Republic of Korea

The Republic of Korea (ROK) has enjoyed rapid economic growth and development over the last 30 years. Rapid increases in energy use—especially petroleum, natural gas, and electricity, and especially in the industrial and transport sectors—have fueled the ROK's economic growth, but with limited fossil fuel resources of its own, the result has been that the ROK is almost entirely dependent on energy imports. The article that follows summarizes the recent trends in the ROK energy sector, including trends in energy demand and supply, and trends in economic, demographic, and other activities that underlie trends in energy use. The ROK has been experiencing drastic changes in its energy system, mainly induced by industrial, supply security, and environmental concerns, and energy policies in the ROK have evolved over the years to address such challenges through measures such as privatization of energy-sector activities, emphases on enhancing energy security through development of energy efficiency, nuclear power, and renewable energy, and a related focus on reducing greenhouse gas emissions. The assembly of a model for evaluating energy futures in the ROK (ROK2010 LEAP) is described, and results of several policy-based scenarios focused on different levels of nuclear energy utilization are described, and their impacts on of energy supply and demand in the ROK through the year 2030 are explored, along with their implications for national energy security and long-term policy plans. Nuclear power continues to hold a crucial position in the ROK's energy policy, but aggressive expansion of nuclear power alone, even if possible given post-Fukushima global concerns, will not be sufficient to attain the ROK's “green economy” and greenhouse gas emissions reduction goals.     

Asean energy demand: Current trends and future outlook

We analyze trends in commercial energy consumption, changes in the fuel-mix, and the relation between energy consumption and economic growth in the ASEAN region from 1960 to 1986. The structure of energy demand is examined at the sectoral level to identify systematic variations over time and across countries. Factors responsible for high demand growth changes in the demand structure are identified. The oil substitution that has taken place since 1980 is studied, and the potential for further substitution analyzed. Finally, a median projection of energy demand to the year 2000 is presented.     

World transport energy demand modelling : Methodology and elasticities

This paper presents the International Energy Agency's (IEA) approach of modelling transport energy demand. Fuel demand, which is not a demand per se, is derived, whenever possible, from the economic activity in the transport sector and not estimated directly, ie using one equation or (simultaneous) equation system. In general, the transport models employ a ‘two-step-approach’: in the first step, transport activity, the sector's relevant energy service, is estimated econometrically. In the second step, the transport activity projections are then combined with estimates of efficiency improvements, car turnover rates and diesel/gasoline penetration assumptions in order to arrive at projections of fuel demand. The principal advantages of this approach are that the relevant energy services are modelled and that, for model simulation, efficiency improvements can be dealt with explicitly. The effectiveness of economic instruments is a function of the reaction of consumers (and businesses) to income and price changes. An in-depth understanding of income and price elasticities of transport demand and transport energy demand is important in order to be able to assess the effectiveness of policies considered. The paper also shows the underlying long-term income and price elasticities for OECD and non-OECD regions.     

Biomass energy in Brazil : Past activities and perspectives

Historically, biomass has provided a large share of Brazil's energy supply. Despite its relevance, the success of some biomass programs has been constrained by short-term priorities to the detriment of long-term policies. The potential of biomass will only be accomplished if further activities are focused on sustainability in a broader sense. Arnaldo Walter, State University of Campinas, Brazil assesses bioenergy use in the country, highlighting past programs, activities and barriers to accomplishing future goals.     

Renewable energy development in China: Resource assessment, technology status, and greenhouse gas mitigation potential

China has become the third largest energy user in the world, and its coal-dominated energy structure implies high CO₂ emissions. The amount of CO₂ emissions from China may surpass that of the United States within 20–30 years, making China the world's largest source of greenhouse gases by 2020.

Currently, renewable energy resources (except for hydropower) account for only a fraction of China's total energy consumption. However, China has abundant solar energy resources. More than two thirds of China receives an annual total insolation that exceeds 5.9 GJ/m2 (1,639 kWh/m²) with more than 2,200 hours of sunshine a year. Wind energy potential in China is about 3,200 GW, of which 253 GW is deemed technically exploitable. China has a wide range of biomass resources that can be used for energy supply and high temperature geothermal resources suitable for power generation located mainly in Tibet and Yunnan provinces.

Renewable energy technologies have been actively deployed in China. Although PV power stations have not being connected to the national grid, total installed capacity was 3 MW in 1994. Solar water heaters are by far the largest solar thermal application in China with a total installed capacity of 3.3 million m² in 1994. By the end of 1995, total installed capacity of grid-connected wind power plants had reached 36 MW. Also, over 140,000 small wind generators ranging in size from 50 W to 5 kW have been deployed with a total installed capacity of 17 MW. China is a world leader in the development and application of anaerobic technologies for the production of fuel gas and waste treatment and has by far the largest biomass gasification R&D capacity in the.

Although renewable energy is projected to play a small role in future electricity generation, it is expected to be much more significant in the total energy sector. Under one scenario, renewable energy other than hydro provides up to 4% of the total energy supply and 88 million tons of carbon emission reduction by 2020. The estimated growth in greenhouse gas emissions, as well as serious local and regional environmental pollution problems caused by combustion of fossil fuels, provide strong arguments for the development of renewable energy resources.