Cars go green but emissions grow
Electric cars can be only as green as the electricity they use, says S.Ananthanarayanan.
India is pursuing a scheme named Faster Adoption and Manufacturing of Hybrid and Electric Vehicles (FAME), launched earlier this yer with an outlay of Rs 800 crore. The objective is said to be conservation of energy and help in reducing environmental pollution.
And in the week just before the Global summit at Paris to combat climate change, a promotional motor rally, the ‘3-Cities Fame India Eco Drive’ was flagged off at the Red Fort in New Delhi and also in other cities.
Electric cars have become feasible with the development of improved storage batteries and are being promoted in many parts of the world as a green option. While there are benefits of lower fuel costs and reduced emissions, compared to petrol or diesel
driven vehicles, the heavy price tag, which used to be a major dis-incentive, has been getting progressively lighter. A question however, is whether the benefits in respect of damage to the environment, are actually there even when the electric cars are used
in India.
A first benefit of electric cars is the fuel economy. An electric car consumes less than twenty units (kilo watt hours) do a hundred kms. At even Rs 10/- per unit, this is Rs 2/- per km, which is good going. A normal car may take six litres of petrol,
which can cost Rs 500/- leading to a fuel cost of Rs 5/- per km. The economy comes from the fact that an electric motor can convert electric energy to drive the car at with about 60% efficiency, against not more than 20% of chemical energy of fuel by a petrol
engine. Electric cars also make use of regenerative braking, which recovers some of the energy used to speed up. And then, there is the pricing of electricity and petrol. One negative that that is mentioned is that electric cars need to plug in for a few hours
to be recharged, but this may not matter as the cars can go well over a hundred km on a full charge.
Electric cars were first priced very high, because of the cost of the Lithium-ion, rechargeable battery, but costs have come down, and with incentives that the government offers to promote electric cars, their use has become attractive, even economical.
And the government cites the reduction of the imports of petroleum as another ground to support increased use of electric cars.
Environment cost
A more important reason to use electric cars, however, seems to be the impression that electric cars, unlike petrol or diesel driven cars, are non-polluting. Whether this is true, of course, depends on the environmental cost of the electricity that is
used. This is where countries like India, a large part of whose electricity generation is based on coal, would lose out. An independent research group which calls itself ‘Shrink That Footprint’, which provides information and seeks to help people who are interested
in reducing their climate impact, has published authoritative data of carbon impact of each km of electric car use, depending on the country where the electricity is drawn.
We can see from table 1 that the carbon impact of an electric car running for 1 km, in countries where electricity is predominantly coal based, as in India, South Africa, Australia, Indonesia and
China, is more than twice that in a great many developed countries. The high emission figures against India may be because of the poor quality of Indian coal and also our very high transmission losses. While the figures are of 2009 and there has been growth
in renewable energy sources in the US and Europe and many parts of the world, in India, the growth in coal based power has kept pace with the growth in renewables (Table 3).
It is hence not likely that the comparative position of India has changed to any great extent. The figures indicated are the total carbon impact, and include the carbon impact, per km, of the manufacture of electric cars. This cost comes to 70 grams C02
per km, and in the case of Paraguay, where the electricity is entirely from hydroelectric sources, there is no other impact of using electric cars.
Another exercise carried out by the research group is to work out the fuel efficiency of the petrol car which is equivalent to an electric car working in different countries. We can see from table 2 that thanks to the high emission impact of electricity
in India, the electric car in India has the footprint of a petrol car that works at 8.5 km per litre of petrol. As petrol cars in India regularly do a lot better than this, switching to electric cars India would lead to a net increase in emission of GHG and
pollutants. On the other hand, attaining the low coal-use level of even Turkey, which has mixed power generation, although heavily fossil based, would place electric cars along with petrol cars that run for 17 km/litre.
Although India is making progress in creating capacity for solar and wind power, coal based capacity will still be important, for decades. A leading major economic consultancy firm says that India’s energy emission growth was the world’s highest, at 8.2%
in 2014. So long as coal based power is dominant, introducing electric cars would amount, essentially, to replacing a part of the oil-based energy for transport with coal based energy of greater carbon impact. The outlay for promoting electric cars through
FAME in the coming years is said to be Rs 14,000 crore. Investment instead in public transport would actually help the environment and be equally effective in curbing import of petroleum
(Courtesy simplescience.in)