Global warming, caused by greenhouse gases emitted by the human society, is a challenge that we cannot ignore anymore. The pasts few years have seen a worldwide rise in the awareness of this environmental problem, to such an extent that all communities are now looking into how to reduce CO2 emissions resulting from the use of fossil fuels.
What is the major cause in the rise of CO2 emissions? In modern western societies, transportation has proved to be one of the major sources of CO2 emissions. Reducing transport related CO2 emissions may be achieved by policy decisions as well as by technological improvements. On the one hand, communities are developing the public transport offer and create incentives for individuals to commute in the "greenest" way. On the other hand, vehicle manufacturers rivalise in creativity to develop low-consumption cars. Although developing evermore-economic cars such as hybrids, these vehicles still result in emitting greenhouse gases and simply delay the problem of global warming.
Is there a viable way to reduce CO2 emissions caused by transport? Every body has been dreaming of proposing zero-emission vehicles for the individual commuter. Different technologies have been applied, from fuel cells to electric engines, but none have met the expectations of the consumer, be it economic or performance. The Bangalore based Indian REVA Electric Car Company has achieved the challenge of developing a zero-emission electric car, meeting the needs of urban commuters for an affordable price (comparable to the price of a small city car). While it still does not allow travelling long distances, the REVAi is the ideal car for households needing a way to be independent in their day to day commuting and covers the needs of most people we meet in traffic jams. For individuals eager to make a difference in their impact on global warming, going electric is certainly the best available choice.
Are electric vehicles emission free? While the emission of CO2 of the REVAis nil itself, critics often state that driving an electric car is simply relocating the problem to the production of electricity. It is true that a thermal power plant producing electricity emits greenhouse gases and makes an inefficient use of energy, just as internal combustion engines. Nevertheless, a recent study by the Swiss Federal Institute for Materials Science and Technologies has torn down this pre-conceived idea, by studying the entire life cycle of different modes of combustible for individual cars.
So how much cleaner did electric vehicles prove to be? This study has looked into all energy requirements and gas emissions related to producing the fuel (be it gas, diesel, bio-fuels or electricity), and the emissions related to the use of this fuel. It has shown that because of production of these different types of fuels and of energy efficiencies of the different engines, electric mobility was unbeatable at all stages! The figure bellow shows the results of a comparison between an electric vehicle charged with the European electricity mix (largely relying on thermal power plants), an electric vehicle charged with solar panels (renewable energy) and the usual combustion engine fuelled at the petrol station. Even in the case of the EU electricity mix, over 50% of the CO2 emissions are reduced!
Figure 1: comparison of greenhouse gas emitted for driving 1 km for three types of cars, traditional internal combustion car running on gasoline, electric car charged with the EU electricity mix and electric car charged with solar electricity. The black part of the chart ("well-to-tank") represents the CO2 equivalent emissions to produce the energy to run the car, i.e. to produce the gasoline or the electricity for running 1 km. The grey part represents the emissions related to constructing the road and the car, it is accepted to be the same for all scenarios. Finally, the red part represents the CO2 emissions while operating the car, i.e. burning the gasoline in the engine. Note that the operation of an electric car doesn't emit any CO2! (Source: Widmer et al., 2007, Empa)
Does driving a REVAi make a difference Reducing the greenhouse gas emissions related to transport asks for improvements at both ends: the production of the fuel and the use of the fuel. Driving electric already meets the objectives at one end, while electricity production is under constant improvement. The day you will be able to charge your REVAi with electricity produced a 100 % with renewable energies, such as hydro-power, wind-power or solar panels, you will be in position to proudly state that you emit practically ZERO greenhouse gases for your transport needs.
Winning the fight against climate change will result from a combination or individual efforts and policy measures. Deciding to drive an electric car for your urban needs definitely makes a difference, and leaves no doubts regarding the importance of the reduction of greenhouse gas emissions.