Energy use, cost and CO2 emissions of electric cars

We examine efficiency, costs and greenhouse gas emissions of current and future electric cars (EV), including the impact from charging EV on electricity demand and infrastructure for generation and distribution.Uncoordinated charging would increase national peak load by 7% at 30% penetration rate of EV and household peak load by 54%, which may exceed the capacity of existing electricity distribution infrastructure. At 30% penetration of EV, off-peak charging would result in a 20% higher, more stable base load and no additional peak load at the national level and up to 7% higher peak load at the household level. Therefore, if off-peak charging is successfully introduced, electric driving need not require additional generation capacity, even in case of 100% switch to electric vehicles.GHG emissions from electric driving depend most on the fuel type (coal or natural gas) used in the generation of electricity for charging, and range between 0 g km⁻¹ (using renewables) and 155 g km⁻¹ (using electricity from an old coal-based plant). Based on the generation capacity projected for the Netherlands in 2015, electricity for EV charging would largely be generated using natural gas, emitting 35-77 g CO_2 eq km⁻¹.We find that total cost of ownership (TCO) of current EV are uncompetitive with regular cars and series hybrid cars by more than 800 € year⁻¹. TCO of future wheel motor PHEV may become competitive when batteries cost 400 € kWh⁻¹, even without tax incentives, as long as one battery pack can last for the lifespan of the vehicle. However, TCO of future battery powered cars is at least 25% higher than of series hybrid or regular cars. This cost gap remains unless cost of batteries drops to 150 € kWh⁻¹ in the future. Variations in driving cost from charging patterns have negligible influence on TCO.GHG abatement costs using plug-in hybrid cars are currently 400-1400 € tonne⁻¹ CO_2 eq and may come down to −100 to 300 € tonne⁻¹. Abatement cost using battery powered cars are currently above 1900 € tonne⁻¹ and are not projected to drop below 300-800 € tonne⁻¹.     

Energy analysis of electric vehicles using batteries or fuel cells through well-to-wheel driving cycle simulations

This work presents a study of the energy and environmental balances for electric vehicles using batteries or fuel cells, through the methodology of the well to wheel (WTW) analysis, applied to ECE-EUDC driving cycle simulations.     

Computational Fluid Dynamics for Architectural Design

There are many ‘compelling possibilities’ for computational fluid dynamics (CFD) in architecture, as demonstrated by its successful adoption in the aerospace, automotive and product manufacturing industries. Sawako Kaijima, Roland Bouffanais, Karen Willcox and Suresh Naidu of ARCH-CFD, a research initiative at the International Design Centre established by the Singapore University of Technology and Design (SUTD) and the Massachusetts Institute of Technology (MIT), explore CFD's potential.     

Off-board regeneration of ammonia borane for use as a hydrogen carrier for automotive fuel cells

Ammonia borane (AB) is a promising chemical hydrogen storage material because of its high H₂ intrinsic material capacity and the exothermicity of the dehydrogenation reactions. A major technical barrier for AB, however, is in the development of an energy-efficient regeneration scheme. This paper examines three promising regeneration schemes that are in various stages of development and verification in the laboratory. The first scheme utilizes a thiol to digest the spent fuel and requires reforming formic acid to close the fuel cycle. The second scheme utilizes an alcohol to digest the spent fuel, but not all steps in the process have been formulated or tested. The third scheme is a single-reactor process that uses hydrazine to regenerate spent AB, but the production of hydrazine from hydrogen is itself not a trivial process. Engineering flowsheets were constructed for each of the three regeneration schemes and the process energy requirements for each scheme were calculated. Additionally, total energy requirements across the entire chain of production, delivery, storage, recovery, and regeneration were evaluated to determine the total cycle well-to-tank energy efficiency and greenhouse gas emissions. The well-to-tank efficiency ranges from a low of 8% in one version of the third regeneration scheme to as high as 37% in the second scheme if the missing process steps were to have no impact on efficiency. The estimated greenhouse gas emissions are between 20 and 100 kg CO₂-equivalent per kg H₂ delivered to the vehicle.     

Alane hydrogen storage for automotive fuel cells - Off-board regeneration processes and efficiencies

Alane is considered an attractive carrier of hydrogen for on-board light-duty vehicle hydrogen storage systems because of its high intrinsic capacity (10.1 wt% H₂), small heat of formation (∼7 kJ/mol H₂), and fast apparent decomposition kinetics. Regeneration of spent Al by direct hydrogenation is impractical due to the extremely high hydrogen equilibrium pressure required (∼7000 bar). This paper examines the off-board regeneration of alane using a three-step organometallic process. In the first step, a relatively stable adduct of a tertiary amine and alane is formed from elemental aluminum and hydrogen gas under moderate conditions of temperature and pressure. The second step involves transamination of the adduct by a second tertiary amine to form a secondary tertiary amine-alane adduct that is less stable than the first adduct. This secondary amine alane adduct is thermally decomposed in the final step to yield alane and the secondary amine for reuse in the process. All reagents, except aluminum and hydrogen, are recovered and recycled. Two process flowsheets have been constructed, and energy consumption in each step of the regeneration process has been calculated. Additionally, total energy requirements across the entire chain of production, delivery, storage, recovery, and regeneration has been evaluated to determine the overall well-to-tank efficiency and greenhouse gas emissions. In one flowsheet, the well-to-tank efficiency is ∼24.2% which improves to ∼42.1% if waste heat is freely available from industrial sources. The estimated greenhouse gas emissions are 31.6 kg CO₂ (eq) per kg H₂ delivered to the vehicle and reduce to 20.6 kg/kg-H₂ if free waste heat is readily available.     

一个正在西安崛起的新型钛产业基地

概述了西部钛业公司的发展历程,生产规模及技术优势.介绍了西北有色金属研究院(集团)近年来钛产业的发展情况,并对未来作出展望.     

一个正在西安崛起的新型钛产业基地

概述了西部钛业公司的发展历程,生产规模及技术优势.介绍了西北有色金属研究院(集团)近年来钛产业的发展情况,并对未来作出展望.