Car & Vehicle

EV Home Charging Cost Calculator

What charging at home costs on your own tariff, counting the losses between the socket and the battery.

7 inputs Free, no sign-up

Your figures

From the handbook or the manufacturer's specification. Usable capacity is a little below the gross figure, because a buffer is held back at each end to protect the cells - and it differs by variant, so it is not filled in here.

From your own bill for home charging, or the price shown on the charger for a public one. Public rates are commonly several times the domestic tariff.

Optional. Add it to see how far the overnight charge takes you.

Leave blank for this page's 85% assumption. Slow home charging is usually a little less efficient than fast charging, because the charger runs for longer at a lower load.

Try an example

Result

Your result

Enter your figures and the result appears here.

Estimates only. Rates, fees and specifications change. Confirm against the official source before you rely on a figure — see our disclaimer.

About this calculator

Charging at home is the cheapest way to run an electric car, and it is worth knowing by how much. A domestic unit in India commonly costs a third or less of what a public fast charger asks, which is a bigger difference than the one between most pairs of cars.

This page takes your battery, your overnight charge window and your own tariff, and counts the energy the meter sees rather than the energy that reaches the cells.

How to use this calculator

  1. Enter the usable battery capacity from the handbook.
  2. Set the charge you plug in on and the charge you want by morning.
  3. Enter the rate from your own electricity bill. Use the marginal rate for your slab rather than the average across the bill.
  4. Add your efficiency in km/kWh if you want the range the charge buys.

The formula

Energy into battery = Capacity x (Morning - Plug-in) / 100
Energy from supply  = Energy into battery / Charging efficiency
Cost                = Energy from supply x Your rate

The efficiency figure is an assumption and is named as one in the result. If you have a meter on the charging point, the ratio between what it reads and what the car reports is your real number — put it in.

SymbolMeaningUnit
Capacity Usable battery capacity kWh
Rate Your marginal tariff ₹/kWh
Efficiency Share reaching the battery %

Worked example

A 40 kWh battery from 20% to 100% at ₹8 a unit:

Into battery = 40 x 0.80  = 32 kWh
From supply  = 32 / 0.85  = 37.65 kWh
Cost         = 37.65 x 8  = 301.18

At 6 km/kWh that is 192 km of range for about three hundred rupees, or ₹1.57 a kilometre.

Notes and limits

  • Domestic tariffs in India are usually slabbed, so charging a car can push your consumption into a dearer band. The marginal rate is the one that matters, and it is on the bill.
  • Some states offer a separate EV tariff or a time-of-day rate that is cheaper overnight. If yours does, use that figure.
  • A 15 A household socket charges slowly — often 2.5 to 3 kW. That is fine overnight and useless in an hour. The EV charging time calculator says how long it takes.
  • Charging from a wall box is generally a little more efficient than from a portable cable on a household socket, because the losses are proportionally smaller at a higher rate.
  • Solar on the roof changes this calculation completely, and the right rate to enter is then what the unit would otherwise have earned you, not what you pay the utility.

What this calculation assumes

  • Charging efficiency defaults to 85% and is named in the result as an assumption.
  • The rate entered applies to every unit charged; tariff slabs are not modelled.
  • Battery capacity and tariff are figures you entered.

Frequently asked questions

How much does it cost to charge an EV at home?

Multiply the energy you are adding by your tariff and divide by the charging efficiency. A 40 kWh battery from 20% to 100% at ₹8 a unit costs about ₹301 at 85% efficiency.

Which electricity rate should I use?

The marginal rate for your slab, not the average across the bill. Domestic tariffs step up with consumption, and a car charging every night adds enough units to matter.

Will charging at home increase my bill a lot?

It will be visible. Driving 1,000 km a month at 6 km/kWh is about 167 kWh into the battery and nearly 200 off the meter - which for many households is a substantial addition to the monthly units.

Do I need a special charger?

Not to charge slowly. A 15 A socket works overnight for most daily distances. A wall box charges considerably faster and is usually a little more efficient, which is a separate question from this calculation.

Related calculators