Dinesh Mohan, Geetam Tiwari, Sudipto Mukherjee and Anoop Chawla
SMALL, LOW COST HIGH EFFICIENCY VEHICLES AND FUTURE URBAN TRANSPORT
Ever since the appearance of the automobile in the beginning of the 20th century, almost all transportation planning and vehicle design was done only with the objective of increasing speeds and reducing congestion on our roads. By the beginning of the 21st century three more concerns were added: depletion of oil resources within 15 – 30 years, unhealthy pollution levels in urban areas, and rising road traffic injury and death rates.
The release of the Intergovernmental Panel on Climate Change (IPCC) report in 2008 has changed the ground rules further. According to one scenario, in order to limit the average increase in global temperatures to a maximum of 2.4°C, CO2 emissions would need to peak by 2015 at the latest, and fall between 50% and 85% below 2000 levels by 2050. This will require a major reduction in emissions from the vehicle fleet, reduction in use of personal transport and modification in our behaviour to reduce number and length of trips. According to the International Energy Agency, India will overtake Japan before 2025 to become the world’s third-largest net importer of oil, after the United States and China. This will put tremendous pressure on us to start reducing fossil fuel energy consumption by motor vehicles before 2015.
The implications of the IPCC report are at one level very simple – if the human race has to survive it has to limit CO2 emissions in a very short time. For us in India, it means that while the poorer sections of the population may increase their consumption to reach “comfortable” living norms, the richest in India (read car owners) will have to reduce their CO2 emissions like the Europeans. This will have to form the base of our sustainable transport policies for the near and long term future. Therefore, the sales of cars in the future may be accompanied by the introduction of a carbon tax that is proportional to the CO2 produced per km by vehicles. This would then justify the design and production of a mini car if it results in the overall reduction of CO2 emissions by the motor vehicle fleet in India. This can happen if there is an average downsizing of the fleet, larger vehicle owners shift to small ones and motorcycle owners do not shift to cars.
This report examines the possibility of producing a mini car that satisfies the concerns raised above. Such a car is termed the proposed small car (PSC) in this report. The design recommendations of the PSC are based on the following assumptions and associated criteria:
Considerations for small car design
The traditional car is called on to do too many things. This results in all current cars being grossly over-powered for normal urban and suburban use. It means that their fuel efficiency and emissions, because of unnecessary mass and engine performance, are far from ideal for the cities of Asia. Their size is a major limitation in conditions of congestion. These factors are especially relevant in the heterogeneous traffic of the megacities of India. There is an obvious need for an urban-specific vehicle with limited speed capability specifically for the needs of Indian cities.
Suggested design criteria
If the PSC is designed with an engine capacity around 600 cc, then the CO2 emissions can be expected to be as low as 80 g/km and fuel consumption around 30 km/l with optimisation of the power unit and the drive train. A designed maximum speed of 60 km/h, can bring significant benefits in terms of reducing CO2 emissions and fuel consumption. Such a car could represent a 5% reduction both in total expected fleet CO2 emissions and fuel consumption for every 10% increase in the total fleet share. If it is accepted that the proposed car does not exceed 60 km/h, and is prohibited from roads which have a higher speed limit than that, then the safety requirements become very different from the normal European mini-car which has to meet the same requirements as all other western designs.
At present, over the life of an urban car in India, the exterior of the vehicle will injure approximately 6 times as many pedestrians and cyclists in comparison to the interior of the car injuring its occupants. Hence great importance must be attached to the exterior geometry and the compliance of the external structures.
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