New Delhi: Even as filling-up a full tank of petrol is fast becoming a pipe dream for many, the alternative as well as futuristic electric powered vehicles seem to offer better running price realisation.

However, caveats apply, especially when the charging time and state-wise electric unit price is applied.

The calculation takes into account the recent rise in petrol prices, which is fast reaching the Rs 100 per litre mark, while diesel is being sold at over Rs 80 per litre.

Consequently, the running cost of EVs comes to Rs 1 per km, Rs 9 for petrol, Rs 6 for diesel and about Rs 2.5 per km for vehicles being run on CNG.

Under the bare minimum conditions, the maths becomes even clearer -- unit price multiplied by battery size is equivalent to the cost of running an EV.

Notably, a home-based 7 kilowatt hour charger takes about 6-8 hours for fully charging a vehicle with a battery size of over 40 KwH. This time period comes down as the battery size decreases.

In terms of cost, special permissions plus wiring is required to install such a system at home or even in flats. Once the infrastructure is in place, the cost really comes down to the unit price.

For instance, in New Delhi, a home based charge will cost around Rs 6.25 per unit. At this range, the full charge for a 40 KwH will be achieved at Rs 250 but will take 6-8 hours.

A 40 KwH battery installed in leading EVs (like in Hyundai Kona Electric) can provide ranges from 350-400 km on a full charge. The running cost of this size of vehicle in a home charge infrastructure will be less than Rs 1 per km.

Now, a fast DC-type charger will do the job in less than an hour but the range here is anywhere from Rs 1,000 to Rs 2,500 per full charge. This would substantially increase the running cost of EVs to close to Rs 6 per km, more than what you will get in a CNG run vehiclke and close to most efficient disel vehicles.

A typical petrol and diesel run vehicle (assuming a mileage of 12 and 15 km per litre, respectively) at current price of fuel (Rs 100 per litre for petrol and Rs 80 per litre for diesel) will give a mileage of RS 8-9 per km and Rs 5-6 per km, respectively.

However, the consideration really comes down to the time one is willing to wait for the EV to get juiced-up.

To resolve the bottleneck, leading industry players are either going in for smaller battery sizes, thereby making cars lighter and faster to charge, or installing home based charging systems at buyers' residences.

For example, Mahindra eVerito uses just a 16 kWh battery that would go up to 180 km in one charge. In home charging conditions, it would need less than four hours to charge fully.

In addition, to wade off range anxiety, some major auto makers are expected to go in for even larger batteries with more than 500 km range in the future as the cost of lithium-ion batteries comes down.

Besides, major players like EESL and others are installing public charging infrastructure to cater to the ever growing need of the nascent segment.

On the range front, a full charge per km depends on the battery size, the drive mode and the in-car electric usage such as AC, heating or music system.

Planning for any contingencies, the companyes have covered the risk by deploying mobile car charging units in major cities.

Still on a comparative basis, EVs trump petrol, on both cost and environmentally friendly scales.

At present, automobile majors such as Tata Motors, Mahindra, MG Motors and Hyundai have come out with pure electric variants and standalone models in India. Tata Motor has Tigor and Nexon EV, MG Motors has ZS EV, Hyundai has Kona Electric and Mahindra has eVerito.

(IANS)