Energies

19 pages, 427 KB

Open AccessArticle

Affects of Mechanical Milling and Metal Oxide Additives on Sorption Kinetics of 1:1 LiNH₂/MgH₂ Mixture

by Donald L. Anton, Christine J. Price and Joshua Gray

Energies 2011, 4(5), 826-844; https://doi.org/10.3390/en4050826 - 20 May 2011

Cited by 10 | Viewed by 8646

The destabilized complex hydride system composed of LiNH₂:MgH₂ (1:1 molar ratio) is one of the leading candidates of hydrogen storage with a reversible hydrogen storage capacity of 8.1 wt%. A low sorption enthalpy of ~32 kJ/mole H₂ was first [...] Read more.

The destabilized complex hydride system composed of LiNH₂:MgH₂ (1:1 molar ratio) is one of the leading candidates of hydrogen storage with a reversible hydrogen storage capacity of 8.1 wt%. A low sorption enthalpy of ~32 kJ/mole H₂ was first predicted by Alapati et al. utilizing first principle density function theory (DFT) calculations and has been subsequently confirmed empirically by Lu et al. through differential thermal analysis (DTA). This enthalpy suggests that favorable sorption kinetics should be obtainable at temperatures in the range of 160 °C to 200 °C. Preliminary experiments reported in the literature indicate that sorption kinetics are substantially lower than expected in this temperature range despite favorable thermodynamics. Systematic isothermal and isobaric sorption experiments were performed using a Sievert’s apparatus to form a baseline data set by which to compare kinetic results over the pressure and temperature range anticipated for use of this material as a hydrogen storage media. Various material preparation methods and compositional modifications were performed in attempts to increase the kinetics while lowering the sorption temperatures. This paper outlines the results of these systematic tests and describes a number of beneficial additions which influence kinetics as well as NH₃ formation. Full article

(This article belongs to the Special Issue Hydrogen Storage)

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8 pages, 1465 KB

Open AccessEditorial

Fukushima: There Are Lessons to Be Learnt, on Both Sides

by Enrico Sciubba

Energies 2011, 4(5), 818-825; https://doi.org/10.3390/en4050818 - 17 May 2011

Cited by 4 | Viewed by 6254

Abstract

On Friday March 11, at 2.46pm (5.46am GMT), an earthquake of magnitude between 8.9 and 9.1 (Richter scale) hit the superficial submarine crust, about 10 km below sea level and about 120 km south-east of the east coast of Japan. Minutes later, a [...] Read more.

On Friday March 11, at 2.46pm (5.46am GMT), an earthquake of magnitude between 8.9 and 9.1 (Richter scale) hit the superficial submarine crust, about 10 km below sea level and about 120 km south-east of the east coast of Japan. Minutes later, a tsunami wave of up to 10 m reached the north-east coast of Japan. Less than two hours later, the Tokyo Electric Power Company (TEPCO) announced that over 4 million households were without power because of the quake-induced power generation and transmission failures. In particular, TEPCO stated that units 1, 2 and 3 at the Fukushima Daiichi nuclear plant and units 1 to 4 at Fukushima Daini stopped automatically because of the quake. This was the beginning of the worst nuclear accident of the last two decades (the Tschernobyl tragedy dates back to 1986). [...] Full article

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14 pages, 161 KB

Open AccessReview

Utilization of Natural Farm Resources for Promoting High Energy Efficiency in Low-Input Organic Farming

by Veronica Arthurson and Lotta Jäderlund

Energies 2011, 4(5), 804-817; https://doi.org/10.3390/en4050804 - 12 May 2011

Cited by 14 | Viewed by 9956

Abstract

Both organic and conventional farming processes require energy input in the form of diesel fuel for farming equipment, animal feed, and fertilizer compounds. The most significant difference between the two methods is the use in conventional farming of mineral fertilizers and pesticides that [...] Read more.

Both organic and conventional farming processes require energy input in the form of diesel fuel for farming equipment, animal feed, and fertilizer compounds. The most significant difference between the two methods is the use in conventional farming of mineral fertilizers and pesticides that are minimally employed in organic management. It is argued that organic farming is more environmentally friendly, given that synthetic fertilizers mainly used at conventional farms are replaced with animal manure and cover crops. Nutrient uptake by plants is additionally enhanced by the effective use of rhizobia and other types of plant growth-promoting bacteria, in combination with arbuscular mycorrhizal fungi. This article aims to compare the amounts and/or types of energy and nutrients required for both farming systems and provide feasible suggestions for the sustainable use of farm resources in combination with good crop yields. Full article

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24 pages, 295 KB

Open AccessArticle

Cost Effective Options for Greenhouse Gas (GHG) Emission Reduction in the Power Sector for Developing Economies — A Case Study in Sabah, Malaysia

by Siong Lee Koh, Yun Seng Lim and Stella Morris

Energies 2011, 4(5), 780-803; https://doi.org/10.3390/en4050780 - 4 May 2011

Cited by 6 | Viewed by 9189

Abstract

With their increasing shares of global emissions developing economies are increasingly being pressured to assume a greater role in global greenhouse gas (GHG) emission reduction. Developed countries have invested tremendously in and proclaimed renewable energy (RE) and associated smart power technologies as solutions [...] Read more.

With their increasing shares of global emissions developing economies are increasingly being pressured to assume a greater role in global greenhouse gas (GHG) emission reduction. Developed countries have invested tremendously in and proclaimed renewable energy (RE) and associated smart power technologies as solutions to meet their energy demands and reduce their GHG emissions at the same time. However, in the developing economies, these technologies may not deliver the desired results because they have their unique characteristics and priorities, which are different from those of the developed world. Many GHG emission reduction technologies are still very expensive and not fully developed. For the developing economies, the adoption threshold may become very high. Therefore, the cost effectiveness and practicality of each technology in reducing GHG emission in the developing economies may be very different from that of the developed economies. In this paper, available RE and other GHG emission reduction technologies are individually considered in a case study on Sabah, one of the 13 states in Malaysia, in order to assess the effects of the individual technologies on GHG emission and electricity cost reductions. Full article

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22 pages, 2300 KB

Open AccessArticle

Large-Scale Battery System Development and User-Specific Driving Behavior Analysis for Emerging Electric-Drive Vehicles

by Jie Wu, Kun Li, Yifei Jiang, Qin Lv, Li Shang and Yihe Sun

Energies 2011, 4(5), 758-779; https://doi.org/10.3390/en4050758 - 29 Apr 2011

Cited by 23 | Viewed by 10661

Abstract

Emerging green-energy transportation, such as hybrid electric vehicles (HEVs) and plug-in HEVs (PHEVs), has a great potential for reduction of fuel consumption and greenhouse emissions. The lithium-ion battery system used in these vehicles, however, is bulky, expensive and unreliable, and has been the primary roadblock for [...] Read more.

Emerging green-energy transportation, such as hybrid electric vehicles (HEVs) and plug-in HEVs (PHEVs), has a great potential for reduction of fuel consumption and greenhouse emissions. The lithium-ion battery system used in these vehicles, however, is bulky, expensive and unreliable, and has been the primary roadblock for transportation electrification. Meanwhile, few studies have considered user-specific driving behavior and its significant impact on (P)HEV fuel efficiency, battery system lifetime, and the environment. This paper presents a detailed investigation of battery system modeling and real-world user-specific driving behavior analysis for emerging electric-drive vehicles. The proposed model is fast to compute and accurate for analyzing battery system run-time and long-term cycle life with a focus on temperature dependent battery system capacity fading and variation. The proposed solution is validated against physical measurement using real-world user driving studies, and has been adopted to facilitate battery system design and optimization. Using the collected real-world hybrid vehicle and run-time driving data, we have also conducted detailed analytical studies of users’ specific driving patterns and their impacts on hybrid vehicle electric energy and fuel efficiency. This work provides a solid foundation for future energy control with emerging electric-drive applications. Full article

(This article belongs to the Special Issue Hybrid Vehicles)

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17 pages, 1137 KB

Open AccessArticle

Novel Field Test Equipment for Lithium-Ion Batteries in Hybrid Electrical Vehicle Applications

by Pontus Svens, Johan Lindstrom, Olle Gelin, Marten Behm and Goran Lindbergh

Energies 2011, 4(5), 741-757; https://doi.org/10.3390/en4050741 - 29 Apr 2011

Cited by 9 | Viewed by 10136

Abstract

Lifetime testing of batteries for hybrid-electrical vehicles (HEV) is usually performed in the lab, either at the cell, module or battery pack level. Complementary field tests of battery packs in vehicles are also often performed. There are, however, difficulties related to field testing [...] Read more.

Lifetime testing of batteries for hybrid-electrical vehicles (HEV) is usually performed in the lab, either at the cell, module or battery pack level. Complementary field tests of battery packs in vehicles are also often performed. There are, however, difficulties related to field testing of battery-packs. Some examples are cost issues and the complexity of continuously collecting battery performance data, such as capacity fade and impedance increase. In this paper, a novel field test equipment designed primarily for lithium-ion battery cell testing is presented. This equipment is intended to be used on conventional vehicles, not hybrid vehicles, as a cheaper and faster field testing method for batteries, compared to full scale HEV testing. The equipment emulates an HEV environment for the tested battery cell by using real time vehicle sensor information and the existing starter battery as load and source. In addition to the emulated battery cycling, periodical capacity and pulse testing capability are implemented as well. This paper begins with presenting some background information about hybrid electrical vehicles and describing the limitations with today’s HEV battery testing. Furthermore, the functionality of the test equipment is described in detail and, finally, results from verification of the equipment are presented and discussed. Full article

(This article belongs to the Special Issue Hybrid Vehicles)

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14 pages, 603 KB

Open AccessArticle

Measuring the Failure of Planning and Its Impact on Sustainable Travel in Dublin, Ireland

by Simon McDonnell and Brian Caulfield

Energies 2011, 4(5), 727-740; https://doi.org/10.3390/en4050727 - 29 Apr 2011

Cited by 2 | Viewed by 7420

Abstract

With the end of the recent housing boom in Dublin, Ireland, it is perhaps a good time to analyze how the commuting and development patterns have been impacted by this unprecedented level of housing construction in recent years. In this research, the authors [...] Read more.

With the end of the recent housing boom in Dublin, Ireland, it is perhaps a good time to analyze how the commuting and development patterns have been impacted by this unprecedented level of housing construction in recent years. In this research, the authors focus specifically on the commuting patterns of those individuals living in the newest housing stock to see how these patterns adhere to the Irish government’s stated transportation and sustainability goals. Data from the 2006 Census of Ireland is used to explore the commuting patterns of individuals living in the four counties that make up Dublin who lived in the most recently constructed housing stock (built between 2001 and 2006, constituting almost one fifth of all housing units in Dublin). The results demonstrate that the latter populations were more likely to have longer commute times and to depart earlier to get to work. The findings also suggest that, despite ambitious government level goals, housing built during the property boom was more likely to be in low-density areas. Full article

(This article belongs to the Special Issue Energy-Friendly Transportation)

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10 pages, 605 KB

Open AccessArticle

AC Power Routing System in Home Based on Demand and Supply Utilizing Distributed Power Sources

by Tsuguhiro Takuno, Yutaro Kitamori, Ryo Takahashi and Takashi Hikihara

Energies 2011, 4(5), 717-726; https://doi.org/10.3390/en4050717 - 26 Apr 2011

Cited by 43 | Viewed by 9764

Abstract

To help reduce consumption of fossil fuels, renewable, natural and distributed power sources are being adopted. These alternative energy sources inevitably show fluctuations in the amount of output power, frequency, and voltage. The suppression of such fluctuations is a key issue to avoid [...] Read more.

To help reduce consumption of fossil fuels, renewable, natural and distributed power sources are being adopted. These alternative energy sources inevitably show fluctuations in the amount of output power, frequency, and voltage. The suppression of such fluctuations is a key issue to avoid disturbances in power grids. A similar situation arises as far as the regulation of in-home power flow is concerned. We focus on the quality of supplied and demanded power in particular. In this paper, an in-home power distribution system based on information of power is proposed. The system is developed in order to integrate power dispatch and communication. The experimental results show the feasibility of new flexible and efficient power management approaches. Full article

(This article belongs to the Special Issue Future Grid)

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Energies, Volume 4, Issue 5 (May 2011) – 8 articles , Pages 717-844

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