In view of the close interrelationship among urban form, transportation and CO2 emissions and constrains toward compact city in Asia, the main focus of this special issue was placed on transportation sector, seeking innovative solutions. Gao and her colleagues’ contribution in this special issue proposed a concept of Behavior Zone as a unit for spatial planning and showed that the estimation of CO2 emission based on Behavior Zones has several advantages as compared to estimation methods based on individual commuting behaviors in Beijing. Another contribution from Pai and Huang studied the travel behavior change of the residents under the influence of Transit Jointed Development (TJD) in Taipei. It concluded that TJD has significant positive effect on the Mass Rapid Transit (MRT) application and helps a lot for driving reduction. Another case study from Shrestha, et al. included in this issue was directed at studying urban accessibility and evaluating different scenarios with regard to the potential towards low carbon transport development in Kathmandu Metropolitan City. This issue also includes a paper dealing with solar power generation in Chinese cities. Zhang et al studied the potential and variance in solar irradiance and PV power generation among Chinese cities and addressed the issue of suitability to develop distributed PV power system in the targeted cities.
Reducing daily transportation carbon emission is one of the main tasks for accomplishing low carbon city. Most existing studies have evaluated transportation carbon emission from industrial structure or micro-economic viewpoint, such as the efficiency of public transportation, work and home relationship, and modal choice of personal trips, but studies on the general impact of personal behaviors on transportation carbon emission is inadequate. A main reason of this relies on the lack of an appropriate spatial unit for integrating people’s greatly diversified behaviors. This study proposes the concept of ‘behavior zone’ (BZ) based on homogeneous assumption of behaviors, in order to analyze people’s traffic behavior and its carbon emission effect by sub-areas. With a survey analysis of the characteristics of people’s daily trips in Beijing’s sample residential areas, the critical indices of BZ are identified including housing price, development intensity and population density, and access to public transportation. With these indices, Beijing is classified into five BZ types, where the modal choice behaviors of inhabitants are projected. Then the total environmental impact of daily trips is estimated based on carbon emission levels of various traffic modes. The results provide a plenty of implications for low carbon strategies such as intensity control by floor-area-ratios and household densities, and adjustment of public transportation services.
In recent years, there are plenty of researches advocating the concept of Transit Oriented Development. Among the mass transit infrastructure projects driven vigorously by the government, the most important one is the construction of MRT. In Taipei Metropolitan Area, the Transit Jointed Development (TJD) is flourishing while the construction of the MRT system is gradually completed. Up to now, there are 82 sites in Taipei MRT system, among which 35 sites have been completed and opened for lease with totally 75,577,369 square meters floor area for 6,317 households. Thus, can TJD improve the Transit Oriented Development become a very important issue. Therefore, this research selected 9 TJD sites for discovering the travel behaviours of the residents before and after they moved in the TJD housing. The research findings show that compared with the data before the residents moved in the residences of TJD, their MRT share for commuting increased from 25.92% to 57.11%, and the car share declined from 28.44% to 15.60%. The total distance reduced was 42.68km, averagely 0.1km reduction per household everyday. In terms of the commute days, the total driving days reduced 373 days, averagely 0.86 day reduction per household; and the total MRT commuting days increased 619 days, averagely 1.42 days increase per household. The totally travel time reduction is 1,133 min, averagely 2.6 min reduction per household; and the cost totally reduced NT$1349, averagely NT$3 reduction per household;. According to the results, TJD has significant positive effect on improving MRT share and reducing car usage. Besides, the results also show that TJD reduce the work commuting distance, commuting time and cost, and helps the government undertaking the Transit Oriented Development.
The concept of ‘low carbon development’ (LCD) emerged from the concerns of developing countries on development policy and climate change rather than climate change alone. As the transport sector in most developing countries is unsustainable, ‘low carbon development in transport’ (LCDT) plans should address approaches to reduce emissions from transport, while maintaining or improving transport, as a catalyser of development. LCDT, as such, may pave a pathway towards LCD. Due to the complexity and uncertainty involved in long term planning tasks, scenario-based planning support systems (PSS) have been regarded as useful tools for exploring future impacts of any kind of plans and policies. Thus, this paper aims at developing an urban accessibility based PSS for evaluating different scenarios of LCDT plans regarding their potential towards low carbon transport development in Kathmandu Metropolitan City (KMC). This modelling framework combines an accessibility analysis and Activity-Structure-Intensity-Fuel (ASIF) framework in a GIS-based modelling platform. Based on interviews with government officials and documents of the Kathmandu Sustainable Urban Transport (KSUT) project, three plans were identified as qualifying for LCDT plans and were evaluated under high and low population growth scenarios. The evaluation shows that there could be an increase in accessibility along with emissions reduction gains for the current public transport (PT) improvement plan as well as for a plan of expanding the number of trolley buses in the PT vehicle fleet, under assumptions of a low population growth scenario. The trolley bus renewal plan can also lead to emissions reduction, but at the expense of accessibility. However, emissions would still be high against the base year for all the plans in the high population growth scenario. Performing a sensitivity analysis, it was concluded that penetration of trolley bus in the vehicle fleet has a great potential towards LCD. The results show that a shift from private to public transport is necessary in all the LCDT plans to realize a LCD in transport.
China has stepped into the accelerating phase of urbanization since the early 1980s, which has boosted the electricity consumption and CO2 emission of the urban area. Most existing studies discussed related issues on national or regional scale from the perspective of the energy sector, but little research has focused on the scale of urban level and topics in urban development. This paper intends to utilize the approach of spatial analysis and spatial statistics to identify the potential and feasibility of Chinese cities in developing distributed photovoltaic power system (D-PVPS) for meeting household electricity demand. The result shows that most Chinese cities are feasible to develop the D-PVPS which can totally cover the present household electricity consumption in residential area, based on the estimation carried out in this paper. Some of the rest cities are also suitable to develop the D-PVPS in the visible future when photoelectric ratio enhances. Finally, policy implications and suggestions are raised to promote the much broader D-PVPS application in Chinese cities under the background of future urbanization.