The Grid an the Electric Car, the other way of looking at a green tech.
During the last years we’ve been hearing about the arrival of the green cars. We already have parallel hybrids as the Toyota Prius (introduced in 1997), and with the advent and improvement of the new Li-ion batteries, we will see a full new range of electric cars: plug-in hybrids, series hybrids (GM planned to launch the Chevy Volt next year), and the purely electric battery-electric cars.
A world full of electric or semi-electric cars might be thought as one with reduced emissions, clean air and no global warming. But if we think deeper, we will see that the electricity that powers those cars has to be generated somehow. And, many times, this generation methods produce more emissions per watt of generated energy than those produced by combustion engines in conventional cars.
The article, ‘How Green Is My Plug-in?’ by John Voelcker in IEEE’s Spectrum, examines the impact on greenhouse gasses emissions depending on the type of car used and the grid in which the car is charged. In it, very interesting data is presented, and it shows that in some countries, using a plug-in electric vehicle, might lead to higher greenhouse gases emissions than those using a car run only on fuel. This article also includes very interesting concepts, as the ‘well to wheels’ measure, which accounts for all the emissions derived from all the activities needed to bring the energy from the oil camp to the wheels of the vehicle. This is because for the same car, the total emissions might vary hugely from using the car in one country with a very ‘green’ grid to one in which most of the electricity is produced through coal-based methods.
Conclusion is that we do have to take into account where the car is to be used before deciding to go for a plug-in car thinking that this way we will spare the world some CO2 tonnes. Also, it means that the fact that China has an ambitious plan to build nuclear plants, thus reducing its dependence on oil and the heavy use of coal-fired plants, is a very good thing, specially taking into account that it is expected to be one of the main markets for electric cars (Chinese battery maker BYD introduced its first plug-in car earlier this year).
My opinion is that improvements in electric cars and batteries are needed and all efforts in that direction are for good. But all that must necessarily be accompanied by clear studies and policies to boost the use of those cars and technologies where they are to make a real difference in emissions. And, at the same time, to hold back their introduction in those countries in which the use of more electricity would yield higher CO2 emissions than using fuel powered equivalents.
