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Report 4 of 5:
Safa
Tempos - Generating Currents - Nepal
Introduction
The Kathmandu Valley is surrounded by hills on all sides and because of its bowl like topography it is very susceptible to air pollution. Increasing urbanisation, industrial activities and automobile traffic all contribute to air pollution in the valley. The population of Kathmandu Valley has now increased to approximately one million. By 2015 it is expected to rise up to levels around 1,800,000. As the urban population grows, it is inevitable that the number of vehicles will increase to meet the demands of the people.
In Kathmandu, pollution is most noticeable in the late spring and early summer months, at which time haze forms through a combination of dust, household smoke and automobile exhaust fumes. Increased emission of automobile exhaust fumes and other urban activities directly effect the mortality rates in a locality, at least among the high risk road side residents, shopkeepers and pedestrians. Petroleum based fuels mainly generate hydro-carbon, carbon-monoxide, carbon-dioxide, oxides of nitrogen, lead, sulphur-dioxide and other suspended particles which are hazardous to health and can cause chronic lung diseases such as bronchitis and asthma, as well as irritation of the respiratory tract, throat and eyes.
Simple observation reveals that much urban air pollution in Nepal, particularly in the Kathmandu Valley, is caused by vehicular emissions. The age and condition of vehicles appears to be a key factor to the contribution of exhaust emission problems and the quality of fuel is also significant. In the past, commercial or public transport vehicles have tended to be badly maintained and often used adulterated fuels. The use of low quality fuel coupled with poor maintenance habits, which are partly attributed to the sparse availability and high cost of spare parts, results in the incomplete combustion of fuel. The excessive exhaust emissions which are produced contribute to a substantial increase in air pollution and consequently, the deterioration of the atmosphere.
Electric vehicles
In order to try and reduce the problem of air pollution from vehicle exhaust emissions, a company in Nepal developed environmentally sound tempos which operate on batteries. The electric tempos cost the same to produce as the diesel or petrol ones. Electric tempos use three batteries as their source of power which need recharging every sixty kilometres. Each battery takes six hours to recharge and therefore almost twenty four hours is needed before the electric tempo can operate again after its batteries have run down. Despite this, an electric tempo has the advantage of having very few moving parts and an electric motor can last several years without any maintenance.
EVCO
The Electrical Vehicle Company, EVCO, manufactures three wheeler electric vehicles. It aims to promote electric vehicles based on clean, renewable hydro-electric power, as the appropriate means of transportation for Nepal and thereby reduce the country’s atmospheric pollution as well as its dependence on imported fossil fuel.
Electrical Equipment
The battery used is designed to withstand regular discharge. It has a life span of about 700 to 750 complete charge and discharge cycles. Each battery produces 6 volts so that the twelve batteries provide a total of 72 volts. A fully charged set of batteries will drive the electric vehicle for a maximum of sixty kilometres.
In order to provide an operating voltage of 12 volts and, at the same time, provide the fairly high (15 amp) current needed by the motor, a DC to DC converter is used to reduce the storage voltage from 72 volts. The converter results in lower losses than would be experienced if resistors were used. A transistorised speed controller system is employed in order to minimise losses in this area and to extend the running time, therefore, reducing operating costs.
An indicator lamp keeps the operator informed of the state of charge of the batteries as it is important that the batteries are recharged before they are more than 80% discharged. The indicator lamp flashes when 70% discharge is reached and then remains on when the battery level falls to the danger level.
All the lighting - front head lights, parking lights, front indicators, side indicators, brake lights and tail lights - run on the 12 volt circuit.
Mechanical Equipment
The electric vehicle only needs one gear because the maximum speed it can travel at is between 30 to 35 kilometres per hour. It has two braking devices. The hand brake which only operates the rear wheels and the foot brake which controls all three wheels when the foot pedal is pressed. The front suspension consists of a rocker arm which is assisted by two helical springs and telescopic hydraulic shock absorbers. The rear suspension works by using longitudinal springs which are assisted by two telescopic shock absorbers.
Servicing Electric Vehicles
Although the maintenance cost of electric vehicles is relatively low, the battery, used as a substitute for fuel, has to be replaced after 750 cycles of its charging and discharging process. This means that an electric vehicle can run for up to 45,000 kilometres before the battery needs to be renewed.
Every 1500 kilometres:
- check gear box oil
- check differential oil
- check brake fluid level in the reservoir
- check and if necessary, adjust brake
- grease the brake and the joints
- check steering box
- clean springs and grease all nipples using multi-purpose grease and suitable grease gun
Every 2000 kilometres, the oil in the sump of the gear box and the differential oil should be completely drained and replaced with new oil. The level of the oil can be checked with a dip stick and should be maintained to the volume of approximately one litre.
The reservoir for the brake fluid is located on the front right side of the cabin and the fluid level should be at the mark shown on the reservoir. If any part of the system is disconnected, the brake fluid should be completely drained and replaced.
Specifications of Electrical Vehicles
| Overall length |
3200mm |
| Overall height |
1600mm |
| Overall width |
1430mm |
| Minimum turning radius |
7000mm |
| Ground clearance |
140mm |
| Unloaded weight |
650kg |
Impact
In April 1998, the Hands On Safa Tempo programme was screened on television for the first time. Evidence has shown that this programme helped to ban the diesel tempos because it influenced people and encouraged them to lobby the government to ban the diesel tempos. By promoting the electric vehicles, Hands On helped to change public opinion.
The electric vehicle business started five years ago. Three years ago, EVCO was one small fleet comprising of ten vehicles. Today the enterprise has grown to more than ten times that size. EVCO is scheduled to supply 100 more electric vehicles and it is currently manufacturing another 40 vehicles. There are 10 EVCO depots and charging stations located throughout Kathmandu which provide over 200 jobs.
EVCO has been the pioneer of electric vehicle development in this region and hopes to be able to extend the distribution of these vehicles to neighbouring countries. Companies from India have taken an interest in the electric vehicles and some of them have visited Nepal to see how the vehicles are charged and how the electrical components are installed. Two of these companies have started to develop electric vehicles in India for themselves.
The people living in Kathmandu have benefited significantly from the use of electric vehicles. Air pollution has reduced and the air quality has improved.
For further information on the electrical tempos please contact:
Electrical Vehicle Company Limited
PO Box 9219
Bhat Bhateni
Kathmandu
Nepal
Tel/Fax: +977-1-420-670
E-mail: evco@mos.com.np |
This document is an output from a project funded by the UK Department for International Development (DFID) for the benefit of developing countries. The views expressed are not necessarily those of the DFID.
Further reading available from ITDG Development Bookshop
Environmental Limits to Motorisation: Non-motorised transport in developed and developing countries
Urs Heierli
This book examines non-motorized transport - bicycles, rickshaws, electric vehicles - as a decisive component in a new strategy for urban development in both developing and developed countries. It provides useful case studies, tables and many illlustrations.
£17.00 1993 200pp SKAT ISBN 3908001412
Electric Vehicles: With Aspects on Developing Countries
Eisenring M
This publication comprises five parts. The first section deals with the history of electric vehicles, the possibilities and the limits of electric vehicles, their usage and potential market, legal regulations, conditions for electric vehicles in developing countries and solar powered vehicles. The second chapter reviews EV technology, power and energy calculations, vehicle conception, batteries, battery charging and drive systems. The focus in the third chapter is on activities and the market situation in the industrialised world and in developing countries. EV energy consumption, environmental impacts and lifecycle economics are studied in the fourth chapter. The final chapter presents future prospects of the development of electric vehicles.
£12.95 1998 PB SKAT ISBN 3908001838
Keys to the Car: Electric and hydrogen vehicles for the 21st century
James Mackenzie
£12.95 World Resources Institute ISBN 0915825937
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