Home EV charging: the electricity bill and installation
A worked NEA bill example shows what charging adds to household costs. Check the connection and wiring before choosing the charger.
Before ordering a home charger, find out how much energy your car needs on an ordinary day. A powerful unit may be unnecessary for a short commute, while a poorly installed small unit can still create a serious electrical problem.
The installation starts with the building and the car. The largest number on the charger box comes later. Your parking position, cable route, approved connection capacity, earthing and the car's onboard charger all affect the result.
Turn the commute into a charging requirement
Consider a household driving 40 km a day in a car using 16 kWh per 100 km. That is 6.4 kWh taken from the battery. If charging efficiency is assumed to be 90%, the meter supplies about 7.1 kWh. Treat these as worked examples. Real figures for a particular model sold in Nepal will differ.
At a steady 3.3 kW, 7.1 kWh takes about 2.2 hours. At 7 kW it takes about an hour. Actual time can vary with the car, supply, temperature and charging control. But the comparison shows why an overnight parking window does not always require a higher-power installation.
AC power also passes through the car's onboard charger. A wall unit rated at 11 kW cannot make a car accept 11 kW if its own AC limit is lower or the available electrical supply does not support it. Sipradi's Nepal Tiago EV brochure identifies the charging equipment options for that model. Read the equivalent local document for yours.
Have the supply inspected
Use a qualified electrician familiar with EV charging. Ask for an assessment of the main connection, existing household load, protective devices, earthing, cable sizing and the route to the parking space. The design should account for other equipment running at the same time, including an induction cooker, pump or water heater.
Do not ask the electrician merely to add a socket where the cable reaches. The charger manufacturer specifies the supply and protection it needs. A dedicated circuit and suitable protective equipment must be designed for the actual installation. A long extension lead through a window is not a permanent charging solution.
For a rented home, obtain written permission before drilling, altering distribution boards or routing a cable over common property. In an apartment, settle parking access and billing with management first. Charging equipment is difficult to use if the assigned bay keeps changing.
Ask for an itemised installation quote. Equipment, cable, protective devices, labour, civil work and any connection upgrade are separate costs. Keep the commissioning record and instructions with the car's documents.
Check the electricity category
There is no single home-EV rate that applies to every connection. NEA explains that electricity tariffs depend on consumer categories and progressive domestic consumption. Check the tariff for your own meter and whether a load or connection change is required with the local distribution office.
Do not assume that ordinary domestic electricity becomes cheaper after 10 pm. Time-of-day arrangements need the correct consumer category and metering. A public charger's selling rate is also different from the electricity tariff paid by its operator.
To estimate the extra bill, calculate added meter units and how they fall within your connection's tariff. Fixed or demand charges, if applicable, need separate treatment. An old online slab table is not enough when tariffs or your billing category have changed.
A worked bill: 200 household units, then 185 charging units
The tariff PDF linked from NEA's consumer tariff page, checked on 3 October 2026, gives these single-phase domestic 30-ampere rates:
| Monthly units | Energy rate per unit | Monthly minimum charge for that consumption band |
|---|---|---|
| First 20 | Rs 5 | Rs 75 |
| 21–30 | Rs 6.50 | Rs 100 |
| 31–50 | Rs 8 | Rs 100 |
| 51–100 | Rs 9.50 | Rs 125 |
| 101–250 | Rs 9.50 | Rs 150 |
| Above 250 | Rs 11 | Rs 200 |
Energy is charged in slabs; only one monthly minimum charge applies. A 200-unit household bill is Rs 1,900: 20 × 5 + 10 × 6.50 + 20 × 8 + 150 × 9.50 + 150.
Our hypothetical commute adds about 185 units over 26 days, bringing consumption to 385. The corresponding bill is Rs 3,910: 20 × 5 + 10 × 6.50 + 20 × 8 + 200 × 9.50 + 135 × 11 + 200.
The extra cost is therefore Rs 2,010, about Rs 1.93/km for 1,040 km. It includes the Rs 50 change in minimum charge. These are calculated examples using rounded charging units, before any rebate, late fee or other account adjustment.
This does not establish that your house can safely supply a charger. Meter amperage tells you about billing and the connection. The electrician still needs to assess spare capacity and protection. A 15-ampere or three-phase connection has a different table. If the household already uses over 250 units, these added units fall in the Rs 11 slab without crossing that threshold.
Check the current NEA tariff page against your own bill. For a public charging stop, use the operator's displayed customer price, including its fees. An operator buys power from NEA at the supply tariff and then sets its own price for drivers. Our EV running-cost calculator accepts an editable electricity estimate. The default figure is our own assumption, so enter the rate you actually pay.
Make charging routine without guessing battery care
Follow the model's daily charge and storage instructions. Some cars recommend occasional full charging to calibrate battery management. Others specify a different routine. Do not apply a universal "never charge above 80%" rule to every battery.
Set the charging schedule around the time you need the car and the supply arrangement. If a setting limits the charge, check that the limit is suitable before a long journey. Keep enough flexibility for an unexpected trip without treating every night as preparation for the longest possible drive.
Inspect the connector and cable for damage. If the socket, plug or equipment becomes unusually hot, charging repeatedly trips protection, or there is a burning smell, stop using it and arrange inspection. After water enters the installation, an electrician should assess it before reuse.
Handover matters
Have the installer show you how to start and stop a session, isolate the equipment safely and recognise a fault. Ask whom to call when the charger refuses a session and which parts carry a warranty.
A good home installation is usually quiet and uneventful. You park, connect and leave with the energy you need. Most of the work happens at the start, when you sort out the load, the protection and the billing.