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Primary Energy Consumption (primary + energy_consumption)

Distribution by Scientific Domains
Engineering50%

Selected Abstracts

Fixed Energy Storage Technology Applied for DC Electrified Railway

IEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 3 2010
Takeshi Konishi Member
Abstract The fixed energy storage system solves the problem of rising energy costs by reducing primary energy consumption. Without a fixed energy storage system, the energy generated by a braking vehicle would be simply converted into waste heat by its braking resistors if no other vehicles are powered simultaneously. Because, as a rule, such synchronized braking and powering cannot be coordinated, the energy storage system stores the energy generated during braking and discharges it again when a vehicle is powered. This greatly reduces primary energy demand in the substation. However, in addition to this energy saving, the energy storage system contributes to the reduction of CO2 emissions. The energy storage system also stabilizes the system voltage. Recent years have witnessed an advance in the energy storage media technology. Developments of energy storage media, lithium ion battery, nickel-metal hydride battery, and electric double-layer capacitors (EDLCs) have been remarkable. This study introduces technologies of fixed energy storage system applicable for DC electrified railway in Japan, and describes two examples of charge/discharge characteristics. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source]

A review on energy, economical, and environmental benefits of the use of CHP systems for small commercial buildings for the North American climate

INTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 14 2009
P. J. Mago
Abstract The use of combined heating and power (CHP) systems to produce both electricity and heat is increasing rapidly due to their high potential of reducing primary energy consumption (PEC), cost, and emissions in domestic, commercial, and industrial applications. In addition to producing both electricity and heat, CHP systems can be coupled with vapor compression systems to provide cooling. This paper analyzes a natural gas engine CHP system together with a vapor compression system for different American climate zones. Performance is measured in terms of operational costs, PEC, and carbon dioxide emissions as a percent of a reference building. The objective of this paper is to compare the performance of a CHP system operating 24,h a day with a system that only operates during typical office hours. Furthermore, the system is optimized based on reducing PEC, minimizing costs, and reducing emissions. In addition, the benefits of CHP systems based on the Energy Star program and the Leadership in Energy and Environmental Design (LEED) program are presented. Results show that, in general, it is more beneficial to operate the CHP system during typical office hours than to operate the system 24,h a day. Also, the CHP system performance strongly depends on the location where it is installed. In addition to reductions in cost, primary energy, and emissions, CHP systems can help achieve the Energy Star label for commercial office buildings and help obtain LEED points that go toward achieving LEED certification status. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Energy Efficiency and Structural Change in the Netherlands, 1980,1995

JOURNAL OF INDUSTRIAL ECOLOGY, Issue 1 2000
Dematerialization, Economic Structure on National Energy Consumption, Influence of Energy Efficiency
Summary International agreement has been reached to reduce greenhouse gas emissions worldwide. One important way of decoupling CO2 emissions from economic growth is by introducing technical measures to improve energy efficiency. In this article, we assess the influence of developments in energy efficiency and economic structure on the total primary energy consumption in the Netherlands over the period 1980, 1995. We find a distinct decoupling of the economic growth and energy consumption of 1.5% per year in the 15-year analysis period. We measure (technical) changes in energy efficiency by changes in the energy consumption per physical unit of production or activity. The aggregate rate of (technical) energy-efficiency improvement was 1.4% per year over the period 1980,1995. The use of physical production indicators makes it possible to measure energy-efficiency developments without detailed surveys at a very low level of aggregation. When we look at economic structural changes over this period, we find that (i) no substantial shift took place at the level of the economic sectors that we distinguish; (ii) the most energy intensive subsectors grew much faster than the total economy; and (iii) at the subsector level, on average, a sizable decoupling of physical production and value added occurred. We conclude that structural changes, that is, changes in the composition of the economy, did not lead to a net decrease in the energy intensity of the Netherlands over the period 1980,1995. [source]

Marginal Land-based Biomass Energy Production in China

JOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 1 2010
Ya Tang
Fast economic development in China has resulted in a significant increase in energy demand. Coal accounts for 70% of China's primary energy consumption and its combustion has caused many environmental and health problems. Energy security and environmental protection requirements are the main drivers for renewable energy development in China. Small farmland and food security make bioenergy derived from corn or sugarcane unacceptable to China: the focus should be on generating bioenergy from ligno-cellulosic feedstock sources. As China cannot afford biomass energy production from its croplands, marginal lands may play an important role in biomass energy production. Although on a small scale, marginal land has already been used for various purposes. It is estimated that some 45 million hm2 of marginal land could be brought into high potential biomass energy production. For the success of such an initiative, it will likely be necessary to develop multipurpose plants. A case study, carried out on marginal land in Ningnan County, Sichuan Province with per capita cropland of 0.07 ha, indicated that some 380 000 tons of dry biomass could be produced each year from annual pruning of mulberry trees. This study supports the feasibility of producing large quantities of biomass from marginal land sources. [source]