CNG and diesel urban buses in India: A life-cycle cost comparison

Delhi’s bus fleet is powered by compressed natural gas (CNG) to address poor air quality. CNG has also been implemented in buses in other Indian cities. We evaluate the life-cycle costs (LCCs) of the Standard (high-floor), low-floor, and low-floor air-conditioned CNG buses and their diesel counterparts in India. Given the importance of fuel economy and fuel price for fuel costs, we analyze the sensitivity of the LCCs to these factors. Also, to assess the effect of fuel prices if they were market driven, we evaluate the LCCs of low-floor air-conditioned CNG and diesel buses in India, but with US fuel prices. Our study aims to inform decision-making regarding the implementation of CNG buses, in concert with an assessment of their environmental and health benefits. The LCCs for CNG are higher than for diesel, but CNG negatively affects the LCC of Standard buses proportionately more than for the low-floor buses. The LCC is significantly higher for the low-floor air-conditioned, relative to that of the low-floor, and in particular the Standard, CNG buses. The significantly higher LCCs for the low-floor and low-floor air-conditioned buses, even for diesel, raises the questions of whether these buses are justified by increased patronage, and how they affect transit supply and affordability. The fuel price and fuel economy of CNG are critical for the competitiveness of CNG relative to diesel buses. This, along with the wide variation in CNG and diesel prices, demonstrates the need for careful fuel pricing policies when CNG is implemented in bus transit

Cost-effectiveness analysis of compressed natural gas implementation in the public bus transit fleet in Delhi, India

Buses in Delhi have been fueled by compressed natural gas (CNG) since 2000, at significant expense, to improve air quality. We evaluate the emissions impacts and cost-effectiveness of CNG buses relative to diesel, in the early 2000s, and more recently – given stricter vehicle emission standards – in Delhi, and the Indian context. We also analyze the hypothetical use of cleaner diesel buses, instead of CNG, in the early 2000s. We consider health critical and greenhouse gas emissions, and capital, operating and maintenance costs, over the service life of buses. A scenario analysis is conducted to assess bus fleet emissions due to the higher costs of CNG buses resulting in some trips being shifted to diesel buses, or other modes. CNG buses in the early 2000s significantly reduced particulate and greenhouse gas emissions, relative to the diesel buses they replaced, and also cleaner diesel buses complying with more stringent BS-III/IV standards. However, cleaner diesel buses would likely have produced emission reductions with similar or better cost-effectiveness ratios relative to CNG. The emission reductions due to low-floor BS-III/IV compliant CNG buses relative to their diesel counterparts, during 2010–2015, were lower, with worse or similar cost-effectiveness ratios, compared with CNG buses relative to diesel in the early 2000s. The scenario analysis revealed that, under a budget constraint, it is preferable to remove diesel buses, and allow other motor vehicles to meet any shortfall in CNG bus supply, strictly from a particulate and nitrogen oxide emissions perspective. So, allowing only CNG buses to operate in Delhi was an effective policy choice in the early 2000s for mitigating local air pollution. We finally explore the implications of our results for mitigating emissions from bus fleets in Delhi and other Indian cities going forward

Operational and financial performance of Delhi\u27s natural gas-fueled public bus transit fleet: A critical evaluation

Following a Supreme Court of India directive, the bus fleet of the Delhi Transport Corporation (DTC) was converted to run on compressed natural gas (CNG) from around 1999 to 2000, to address the city\u27s air pollution. We critically evaluate the operational and financial performance of DTC\u27s bus fleet from 1989–90 to 2010–11 – that is, from ten years prior to CNG implementation until 10 years after – to assess how this performance was affected by the fuel switch, as well as the introduction of low-floor CNG buses. CNG implementation caused a significant reduction in the capacity to deliver transit service at DTC in the initial stages of the fuel transition. Also, it necessitated investments in buses at a considerable cost premium relative to their diesel counterparts. Operating costs per kilometre grew, due to increased fuel expenditures per kilometre, because of the lower fuel economy, and increased maintenance costs and breakdowns per kilometre, on the CNG buses. These costs were further exacerbated by the introduction of the low-floor CNG buses. Despite increased capacity due to the investments in the CNG buses, passenger-kilometres generally declined over our analysis period. As a result, operating costs per passenger-kilometre, and the ratio of operating costs to traffic revenues, have progressively worsened. We conclude that the financial situation resulting from these effects due to CNG implementation may have detracted from the ability to enhance transit capacity and provide transit service overall. Our study also demonstrates the need to analyze policies such as CNG implementation broadly, in terms of conflicts and trade-offs between environmental, and other (transit operation, socio-economic and equity) objectives, rather than narrowly in terms of only environmental outcomes

Estimating and communicating food system impacts: A case study in Montreal, Quebec

Modern food systems are characterized by a range of resource use, environmental, and socioeconomic impacts, resulting from choices made by various actors, including the public, who are "distanced" from these impacts, with important implications for sustainability. In order to make ecologically responsible food choices, the public will need information that is reliable, easily comprehensible, and that allows them to discriminate between these choices in terms of the range of impacts, and their trade-offs with factors such as market price. We illustrate, by means of a case study involving nine variations of two meals of similar nutritional energy content, some challenges and issues associated with estimating and integrating the diverse impacts of food systems, and explore the implications of our results for communicating these impacts in a manner that balances epistemic adequacy with heuristic usefulness in enabling ecologically responsible food choices.Food systems Food choice Environmental impacts Characterization Integration Communication

An analysis of public bus transit performance in Indian cities

Maintaining and enhancing public transit service in Indian cities is important, to meet rapidly growing mass mobility needs, and curb personal motor vehicle activity and its impacts at low cost. Indian cities rely predominantly on buses for public transport, and are likely to continue to do so for years. However, the public bus transit service is inadequate, and unaffordable for the urban poor. The paper explores the factors that contribute to and affect efforts to improve this situation, based on an analysis of the financial and operational performance of the public bus transit service in the four metropolitan centres and four secondary cities during the 1990s. Overall, there were persistent losses, owing to increasing input costs and declining productivity. The losses occurred despite rapidly increasing fares, and ridership declined. The situation, and the ability to address it, is worse in the secondary cities than the metropolitan centres. We suggest a disaggregated approach based on the needs and motivations of different groups in relation to public transit, along with improved operating conditions and policies to internalize costs of personal motor vehicle use, to address the challenge of providing financially viable and affordable public bus transit service.

Bang for the buck: Toward a rapid assessment of urban public transit from multiple perspectives in North America

We present a rapid assessment – using simple metrics based on publicly available data– of how effectively public transit agencies achieve key outcomes, and reconcile trade-offs among these outcomes, from the perspective of transit users, society and the agencies, in the largest 14 cities in North America with a population greater than three million. We assess the trade-offs among service quality, incorporating accessibility, service frequency, and comfort (which are important for transit users); transit ridership per capita (reflecting the society perspective); financial viability from the agency perspective; and affordability of fares for minimum-wage earners. We also assess the overall performance of transit in these cities, considering these perspectives in an integrated manner. Agencies vary widely in achieving and reconciling the above outcomes and trade-offs. Generally speaking, however, agencies that perform well (or badly) on one of these objectives and trade-offs also perform well (or badly) on the others, and in terms of overall transit performance. Finally, we discuss how our assessment may be improved upon, including in terms of better and more nuanced measures, in future work. We suggest that metrics be assessed uniformly and reported regularly across transit agencies, to track and reliably compare their performance over time; and that it would be desirable to understand how transit users and decision makers weigh the relative importance of key objectives, and to incorporate this understanding in assessments of transit performance

What influences satisfaction and loyalty in public transport? A review of the literature

Public transport ridership retention is a challenge for many cities. To develop comprehensive strategies aimed at retaining riders, it is necessary to understand the aspects of public transport that influence users to become loyal to the system. This paper analyses relevant literature regarding the causes of satisfaction and loyalty in public transport. We find that the service factors most associated with satisfaction are on-board cleanliness and comfort, courteous and helpful behaviour from operators, safety, as well as punctuality and frequency of service. On the other hand, loyalty is associated with users’ perceptions of value-for-money, on-board safety and cleanliness, interactions with personnel and the image and commitment to public transport that users feels. Furthermore, the results elucidate that the concept of loyalty is best defined based on users’ intentions to continue using the service, their willingness to recommend it to others, their overall satisfaction, but also and most importantly, their image of and involvement with public transport. Public transport users who have a positive image of the agency and consider public transport an integral component of city life are more likely to demonstrate loyalty and act like ambassadors for public transport agencies