In India, when a person considers buying a conventional car, a lot of attention is paid to the mileage of the car. The mileage (or average) of the car is measured in kmpl (kilometres per litre) in India. In the US, mileage is measured in mpg (miles per gallon).
Example: The Mahindra Verito gives a mileage of 15 kmpl. To cover a distance of 60 km, the car would need 4 litres of petrol. With the price of Petrol being Rs.100 per litre, it would cost Rs.400 to cover the distance.
For electric cars, ‘Range’ refers to the distance an e-car can travel before the battery needs to be recharged. The range of an e-car depends on the capacity of its battery i.e., the amount of electricity it is able to store. It is measured in kWh (kilowatt-hours). If you consume 1 kW of power for 1 hour that means you consume 1 kWh or 1 unit of electricity.
Example: The Mahindra e2o would need 10 units of power for a full charge of 100 km. To cover a distance of 60 km, the car would need 6 units of power. In Delhi, for EVs, at Rs.4.5 per unit power, it would cost Rs.27 to cover the distance (6*4.5=27).
Comparing the costs & mileage/range of the petrol Verito & e2o above give a glancing knowledge of the cost-effectiveness of an e-car. The same topic is explained in detail below.
Electric Car Specifications:
1. Battery Pack: The measurement used to indicate the charge stored by the battery in kWh.
2. Range: If a conventional car has kmpl as an indicator of fuel mileage, its equivalent in EVs is kilometre per charge.
3. Cost of electricity: The price you have to pay for each unit of electricity. A unit of electricity is equal to a kWh.
In Delhi, the govt has fixed electricity @ Rs.4.5 per unit for charging of EVs. In Mumbai, it's Rs.15 per unit and in Bangalore, it is anywhere between Rs.7.28 and Rs.8.90 per unit, which is higher than Delhi but lower than Mumbai.
Let's see a comparison using Tata Nexon EV as an example:
The Nexon EV hosts a 30.2 kWh battery. In Delhi, with Rs.4.5/unit power, charging it fully would cost Rs.135.9 (30.2*4.5=135.9). In Mumbai, it’ll cost Rs.453 and in Bangalore, Rs.244.3. Nexon EV’s certified range is 312 km. With these numbers, the Nexon EV costs Rs.0.44/km (135.9/312=0.44) to run in Delhi, Rs.1.45/km in Mumbai & Rs.0.78/km in Bangalore.
On the other hand, Nexon petrol hosts a 44-litre tank. Filling this tank with petrol at Rs.100/litre costs Rs.4400. Certified mileage for petrol Nexon is 16 kmpl. The range is 704 km (44*16=704). With these numbers, the petrol Nexon costs Rs.6.25/km (4400/704=6.25) to run.
It is very evident that the Nexon EV costs significantly lower than petrol Nexon to run.
Another take:
The Hyundai Kona has a 39 kWh battery. Its certified range is 452 km. It means the e-car consumes 39 units of electricity to cover that 452 km. The car costs 0.08 units of electricity to run a distance of 1 km (39/452=0.08).
A simple way to determine how much electricity does it take to charge an e-car & its cost:
1. Find your e-car’s battery size (in kWh). Eg.,75 kWh
2. Note the certified range of your EV or the average range your present e-car is getting you. Eg.,450 km
3. Look up the cost of electricity in your city/state. Many states are offering subsidized rates for EV charging. Eg., Rs.4.5 per unit in Delhi.
4. Multiply the cost of electricity per unit (or kWh) with the size of the battery. Eg.,4.5*75=Rs.337.5
5. Optional: Consider charging efficiency (85% for home charging, 95% for DC fast charging). Eg.,(337.5/85)*15=Rs.59.6 (additional cost from the energy lost during home charging).
6. Add Point 4 & Point 5. Eg.,337.5+59.6=Rs.397.1 (cost to fully charge your 75 kWh battery from 0-100%).
7. To calculate costs in terms of km: Divide Total Cost (Point 6) by EV’s range (Point 2). Eg.,397.1/450=Rs.0.88 per km.
A European point-of-view:
According to Finland-based EV charging solutions company Virta, in a study based in Finland, an average electric car consumes approximately 0.20 kWh/km. A typical Finnish driver commutes around 16,800 km every year. This makes approximately 47 km driving every day. This means 9.4 kWh electricity consumption per day. When estimating electricity consumption, one should take into account the yearly holiday seasons, driving habits, weather, etc.
Since e-cars are relatively new in India, such international studies give an idea of energy consumption & its costs which occur.
Conclusion:
Most EVs can cover up to 100 km with 15 kWh. Their low energy loss means that they are not very energy-intensive. While petrol & diesel engines convert a maximum of 35% of this energy into driving force, an electric car converts 85% or more.
Battery capacity & vehicle mass are closely related. A 10 kWh increase in battery capacity increases the mass of electric cars by 15 kg, drive range by 40-50 km & their energy consumption by 0.7-1.0 kWh/100 km.
State-of-the-art & mass-produced electric cars are more efficient than first-generation cars produced on a small scale.
Electric cars are a game-changer when it comes to energy management & running costs for drivers. Their electricity consumption and the cost of charging involves various factors to bear in mind so as to optimize expenditure.
